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Abstract
Title: Author: Subject: Date: Clean Water Plan 2009 Denver Regional Council of Governments Regional water quality planning Published ____ (month) _______ (day), 2009
Source of Copies: Number of Pages: ___ Abstract: The Clean Water Plan is the regional water quality management plan mandated by state and federal statutes for water quality planning in the nine-county Denver metropolitan region.
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Abstract
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Table of Contents
Contents
Executive Summary ......................................................................................... 1
DRCOG’s role in regional water quality planning (Clean Water Plan Chapter 1) .............. 1 Clean Water Plan goal and policies (Clean Water Plan Chapter 2) .................................... 1 Implementing the Clean Water Plan (Clean Water Plan Chapter 3) ................................ 1 Regional water quality assessment (Clean Water Plan Chapter 4) ................................. 2 Stormwater and nonpoint pollution sources (Clean Water Plan Chapter 5) .................. 2 Water Quality Infrastructure Planning (Clean Water Plan Chapter 6) ..............................2 Protecting critical environmental resources (Clean Water Plan Chapter 7) ................... 3 Watersheds (Clean Water Plan Chapter 8) ....................................................................... 4
Chapter 1: Introduction....................................................................................5
Chapter 2: Summary of Policy Statements ....................................................7
Regional goal/connection to the Metro Vision Plan (Chapter 1) ......................................7 Stream standards and classifications (Chapter 4) ............................................................7 Impaired stream segments (Chapter 4) ............................................................................7 Stormwater and nonpoint pollution source (NPS) management policy (Chapter 5) .... 8 Wastewater treatment system goals and policies (Chapter 6) ...................................... 8 Biosolids (Chapter 6)......................................................................................................... 9 Critical environmental resources (Chapter 7) .................................................................. 9 Watershed approach (Chapter 8) .................................................................................... 9
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Chapter 3: Clean Water Plan Implementation ........................................... 11
DRCOG’s responsibilities...................................................................................................11 Water Quality Advisory Committee responsibilities ....................................................... 12 Regulatory agency responsibilities ................................................................................. 12 Management Agency Roles and Responsibilities ........................................................... 13 Water quality areas requiring management agencies ................................................... 13 Preferences for management agency designation ..................................................... 14 Required elements of areawide water quality plans................................................... 14 Clean Water Plan assessment process .......................................................................... 16
Chapter 4: Regional Water Quality Assessment ........................................ 19
Standards, classifications and antidegradation designations ..................................... 19 DRCOG policy on classifications and standards ........................................................... 20 Processes to change designations ............................................................................... 20 Impaired stream segments ........................................................................................... 20 DRCOG policy on identification of impaired stream segments ..................................... 21
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Metro Vision Plan water quality goal and policies ........................................................... 5 Coordination with the Metro Vision Plan .......................................................................... 6 Coordination with the State ............................................................................................. 6 Service areas...................................................................................................................... 6
Total Maximum Daily Loads (TMDLs)............................................................ 21
Regulatory TMDL requirements ...................................................................................... 22 TMDL process ................................................................................................................... 22 Challenges to the TMDL program ................................................................................... 23 Relationship to the Clean Water Plan .............................................................................. 23
Chapter 5: Stormwater and Nonpoint Source Management ...................... 25
DRCOG stormwater management policy........................................................................ 25 Nonpoint Source (NPS) management policy .................................................................. 26 Stormwater and the Regional Transportation Plan: Green infrastructure policy ......... 27 Best Management Practices (BMPs)............................................................................... 28 Stormwater permits in Colorado..................................................................................... 28 Extent of impervious surfaces ......................................................................................... 30
Chapter 6: Water Quality Treatment Infrastructure .................................... 31 I. Domestic Wastewater Facility Planning................................................ 31 A. Project review considerations ............................................................... 31 B. Permitting process.................................................................................. 34 II. Industrial Dischargers ............................................................................. 37 III.Other wastewater treatment infrastructure issues .............................. 38
Chapter 7: Critical Environmental Resources ................................................................... 43 Overview........................................................................................................................... 43 Regional policies for critical environmental resources .................................................. 43
Analyses of critical environmental resources .............................................. 44
Wetlands ........................................................................................................................... 44 Riparian Corridors ............................................................................................................ 45 Groundwater .................................................................................................................... 46
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Chapter 8: Watersheds ................................................................................... 47
Watershed-based approachError! Bookmark not defined. Watershed summariesError! Bookmark not defined.
Bear Creek Watershed.................................................................................... 48
Watershed description..................................................................................................... 48 Water quality management ............................................................................................. 48
Beebe Draw Watershed ................................................................................. 51
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Watershed description..................................................................................................... 51 Water quality management ............................................................................................. 51
Big Dry Creek Watershed ............................................................................... 54
Watershed description..................................................................................................... 54 Water quality management ............................................................................................. 54
Boulder/Saint Vrain Watershed .................................................................. 57
Watershed description.................................................................................................. 57 Water quality management .......................................................................................... 57
Chatfield Watershed .................................................................................... 60
Watershed description.................................................................................................. 60 Water quality management .......................................................................................... 60
Cherry Creek Watershed ............................................................................. 63
Watershed description.................................................................................................. 63 Water quality management .......................................................................................... 63
East Plains Watershed ........................................................................................... 66
South Platte Urban Watershed ................................................................... 69
Watershed description.................................................................................................. 69 Water quality management .......................................................................................... 69
Upper Clear Creek Watershed .................................................................... 72
Watershed description.................................................................................................. 72 Water quality management .......................................................................................... 72
Upper South Platte Watershed................................................................... 75
Watershed description.................................................................................................. 75 Water quality management .......................................................................................... 75
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Watershed description.................................................................................................. 66 Water quality management .......................................................................................... 66
LIST OF MAPS AND FIGURES
Figure 1: DRCOG Water Quality Planning Area Figure 2: Industrial Dischargers Figure 3: Map of Bear Creek Watershed Figure 4: Map of the Beebe Draw Watershed Figure 5: Map of the Big Dry Creek Watershed Figure 6: Map of the Boulder/St. Vrain Watershed Figure 7: Map of Chatfield Watershed Figure 8: Map of the Cherry Creek watershed Figure 9: Map of the East Plains Watershed 4 41 50 53 56 59 62 65 68 71 74 77
Figure 10: Map of the South Platte Urban Watershed Figure 11: Map of the Upper Clear Creek Watershed
Figure 12: Map of the Upper South Platte Urban Watershed
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List of Tables
Table 1 : Designated Management Agencies Table 2 : Percentage of imperviousness in Denver region watersheds (2006) Table 3 : Bear Creek Watershed Wastewater Treatment Facilities Table 4 : Beebe Draw Watershed Wastewater Treatment Facilities Table 5 : Big Dry Creek Watershed Wastewater Treatment Facilities Table 6 : Boulder/St. Vrain Creek Watershed Wastewater Treatment Facilities Table 7 : Chatfield Watershed Wastewater Treatment Facilities Table 8 : Cherry Creek Watershed Wastewater Treatment Facilities Table 9 : East Plains Watershed Wastewater Treatment Facilities 17 30 49 52 55
61 64 67 70 73 76
Table 10 : South Platte Urban Watershed Wastewater Treatment Facilities Table 11 : Upper Clear Creek Watershed Wastewater Treatment Facilities
Table 12 : Upper South Platte Watershed Wastewater Treatment Facilities
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List of Maps and Figures
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Executive Summary
DRCOG’s role in regional water quality planning (Clean Water Plan Chapter 1) Under federal and state statutes, the Denver Regional Council of Governments (DRCOG) is charged with developing a regional water quality management plan for the Denver metropolitan region. The DRCOG Clean Water Plan coordinates activities and management plans to protect and enhance water quality within ten watersheds established for the region. DRCOG’s water quality planning area is comprised of Adams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver, Douglas, Gilpin, and Jefferson counties (see Figure 1).
DRCOG’s overall role is to plan and coordinate. The DRCOG Water Quality Advisory Committee (WQAC), through the DRCOG Metro Vision Issues Committee, advises the DRCOG Board of Directors (Board) on regional water quality issues. DRCOG works with a variety of entities to accomplish water quality planning, including counties, cities, designated water quality management agencies, facility operators, the state Water Quality Control Division (WQCD), and federal agencies. Clean Water Plan goal and policies (Clean Water Plan Chapter 2) DRCOG’s regional water quality goal is to restore and maintain the chemical and physical integrity of the region’s waters to ensure clean water for residents and a balanced, healthy ecological community. Policy direction in the Clean Water Plan is consistent with the objectives and goals of the federal Clean Water Act and the state Water Quality Control Act, and commensurate with the levels of funding provided through state and federal sources. The Clean Water Plan is subject to the approval of the state Water Quality Control Commission (WQCC) and the federal Environmental Protection Agency (EPA). Implementing the Clean Water Plan (Clean Water Plan Chapter 3) While DRCOG has the responsibility of developing the regional water quality plan, the agency relies on the efforts of local governments, designated local management agencies and watershed organizations to implement the elements of the Clean Water Plan. All geographic areas within the DRCOG planning region have designated management agencies. Table 1 at the end of Chapter 3 details management agency types and areas of responsibility.
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Executive Summary
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The Clean Water Plan is an element of the DRCOG Metro Vision Plan. The Metro Vision Plan is the regional plan that addresses transportation, land use, air quality, water quality and parks/open space in order to maintain and improve the region’s quality of life. The Clean Water Plan outlines the policies of the DRCOG Board for watersheds, wastewater treatment systems and service, point and nonpoint sources of pollution, and protection of the aquatic ecological community.
Regional water quality assessment (Clean Water Plan Chapter 4) Federal and state regulations require water quality assessments reporting the status of the state’s water quality and water quality management programs. Based on this information, the WQCC establishes stream uses, classifications, standards and antidegradation designations for all water bodies. The WQCC uses a triennial review process for rulemaking to review and/or revise these designations. DRCOG works with management agencies to review and recommend changes that are consistent with the Clean Water Plan. Section 303(d) of the federal Clean Water Act requires the state to identify and list “impaired segments” where the water body does not meet established water quality standards. For each segment on the list, the state must establish Total Maximum Daily Loads (TMDLs) which are a pollutant allocation/management mechanism. The WQCD is tasked with preparing TMDLs for review and approval by the EPA. DRCOG’s role in the process is to provide adequate, updated information and assist management agencies involved in carrying out the TMDL process themselves, if requested. Following EPA approval of a TMDL, DRCOG will incorporate findings of the TMDL into the appropriate watershed-specific Technical Appendices of the Clean Water Plan. Stormwater and nonpoint pollution sources (Clean Water Plan Chapter 5) The Clean Water Act requires areawide water quality management plans to address stormwater management and nonpoint pollution sources (NPS). In Colorado, the WQCD administers stormwater permits as part of the Colorado Discharge Permit System (CDPS). The purpose of the permits is to reduce pollutants discharged to waterways that originate from stormwater runoff. Federal regulations require that medium and large municipal storm systems hold a stormwater permit. Also, industrial stormwater sources are required to have stormwater permits. DRCOG’s role is to facilitate information exchange regarding stormwater and nonpoint source pollution best management practices (BMPs). It acts in an advisory capacity to permitted municipalities. Partner agencies in this effort include the Urban Drainage and Flood Control District (UDFCD), the Colorado Stormwater Council, and others. Water Quality Infrastructure Planning (Clean Water Plan Chapter 6) DRCOG’s goal is to encourage the provision of reasonable, feasible and economical wastewater service to any particular area. This chapter covers the planning processes for domestic wastewater treatment works, industrial dischargers, other treatment works (lift stations and interceptors), and onsite treatment systems.
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The state Water Quality Control Act requires that the responsible agency obtain a site location approval from the WQCD before a wastewater treatment plant can be constructed or expanded, or before lift stations and major interceptor lines can be built. For new domestic facilities, a review by the appropriate water quality management agency or watershed group
is the first step in the site location approval process. DRCOG also requires that wastewater facility operators submit a Wastewater Utility Plan (WUP) prior to or concurrently with the site application. Each WUP identifies the demand for the treatment system based on forecasted growth and development that has been approved by local governments and is consistent with DRCOG’s Metro Vision Plan. The DRCOG Board reviews all site location approval applications and submits its findings to the WQCD. The DRCOG Board updates the Clean Water Plan to include the new facility once WQCD has issued a new discharge permit. Industrial dischargers are not bound by the same review process. DRCOG will enter a memorandum of understanding with the WQCD, whereby the Division will provide applications for new industrial dischargers to DRCOG, which will comment to the Division directly. Lift stations and interceptor works go through the same process as new domestic works, but wastewater utility plans and discharge permits do not apply. Onsite treatment system management is governed by state and local health departments for systems under 2,000 gallons per day. Otherwise, they are considered wastewater treatment works and subject to the standard DRCOG approval process.
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Protecting critical environmental resources (Clean Water Plan Chapter 7) Local governments and other agencies in the region have identified certain environmental resources as critical regional issues. The Clean Water Plan contains policies addressing wetlands, riparian corridors and groundwater aquifers. Wetlands are a valuable regional resource which serves multiple functions in water quality management. The DRCOG Board supports a no net loss of wetlands policy. Protection of riparian corridors also contributes to reaching water quality goals. DRCOG supports the protection and restoration of riparian corridors throughout the region. Finally, many municipalities in the Denver region rely on groundwater to meet their water needs. Long-range management plans must consider groundwater quality, and groundwater recharge zones must be protected from water quality degradation. The DRCOG Board is responsible for reviewing environmental assessments and other plans that are referred to DRCOG for review and comment. Additional regional environmental issues can be evaluated by the WQAC, the Metro Vision Issues Committee and the DRCOG Board for policy direction on an as-needed basis.
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Watersheds (Clean Water Plan Chapter 8) There are 10 designated watersheds in the Denver region. The DRCOG Board’s goal is to apply an integrated, holistic strategy to protect or attain established beneficial uses of waters within regional watersheds, including protection of water quality. The Clean Water Plan includes maps, watershed descriptions and water quality management information for each watershed. More detailed information for each watershed is available in the Technical Appendices to the Clean Water Plan.
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Chapter 1: Introduction
Water quality management is governed by the federal Clean Water Act and the state Water Quality Control Act. DRCOG’s role, as defined in both federal and state law, is to provide policy direction and plans to coordinate and complement local management and decision-making with regulatory agencies within a regional context. DRCOG is designated under state law as the regional water quality planning agency for the Denver metropolitan area. The DRCOG Metro Vision Plan is the umbrella policy document for the agency. The Metro Vision Plan is the region’s long-range plan that integrates land use, transportation, air quality planning and water quality planning. The Clean Water Plan is an element of the Metro Vision Plan that provides a regional context to protect, maintain and restore water quality through integrated and coordinated water quality planning. Metro Vision Plan water quality goal and policies The Metro Vision Plan established a regional water quality goal and a set of policies to help meet that goal. The Board’s regional water policy goal is to restore and maintain the chemical and physical integrity of the region’s waters to ensure clean water for residents and a balanced, healthy ecological community. The six policies established in the Metro Vision Plan for water quality are:
1. 2.
Watersheds. Water quality planning will be watershed-based.
Wastewater treatment. The Clean Water Plan will identify an effective regional system of wastewater treatment facilities that meets federal and state standards.
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3. Wastewater service. Development should only be allowed in areas where sewer service is already available; where new wastewater facilities can be established consistent with water body uses, classifications, standards, antidegradation designations and the Clean Water Plan; or in areas where onsite treatment systems are deemed appropriate. 4. Stormwater (point source) and nonpoint sources. Local action will reduce pollution from stormwater and nonpoint sources. Development should use practices that maintain and improve the quality of streams and water bodies by managing stormwater runoff. 5. Ecological community. Water quality protection and management initiatives will achieve a balanced community of fish and other aquatic life. These activities should take into account the needs of both the natural environment and other resource uses such as water supply. 6. Quality of water supplies. Integrated resource management programs should be developed that deal effectively with the relationships between water quality management and water supply.
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Coordination with the Metro Vision Plan The Clean Water Plan is an element of the Metro Vision Plan. The primary link to the Metro Vision Plan is through the establishment of wastewater utility service areas (WUSA) and wastewater utility plans (WUP). These WUSA correspond to areas that local governments anticipate will urbanize within the 20+ year Metro Vision Plan planning horizon and thus require centralized wastewater treatment. The Clean Water Plan also anticipates wastewater service areas longer-term (30-50 year) planning horizons. Coordination with the State The Colorado Water Quality Control Commission (WQCC) is the administrative agency responsible for adoption of water quality classifications, standards and antidegradation designations, as well as regulations aimed at achieving compliance with those classifications and standards. In addition to its formal rulemaking role, the WQCC is also responsible for developing water quality policy in Colorado. The Water Quality Control Division (WQCD) is responsible for implementing and enforcing the regulations adopted by the WQCC. The WQCD also provides technical expertise to the WQCC in its rulemaking and other policy-setting activities. The WQCD approves municipal (domestic) wastewater treatment system sites (such as treatment plants, lift stations and interceptors) and issues municipal, industrial wastewater and stormwater discharge permits. The Clean Water Plan identifies five factors for determining consistency of permit and site location approvals: location, sizing, staging, service area, and effluent quality. Three of these (sizing, staging, and service area) are growth related. DRCOG uses forecasts from its regional development plan to calculate sizing and staging needs of treatment facilities. Service areas The Clean Water Plan recognizes two types of service areas: Wastewater utility service areas (WUSA) and CWP planning areas. Service areas are based on local comprehensive plans. Wastewater utility service areas are typically coincident with a locality’s map for future extent of urban development (urban growth boundaries/areas) planned to occur within the 20-year planning horizon. WUSA identify the appropriate boundaries between different wastewater treatment facilities. This enables each facility to conduct its own planning with the assurance that no other facility is planned to serve the same area. Overlapping WUSA will not be recognized in the plan. Local resolution of overlap issues will be required before these areas are designated in the Clean Water Plan. CWP Planning Areas include potential additional service areas anticipated to develop beyond the Metro Vision planning horizon and includes the WUSA. Establishing CWP Planning Areas assists with determining the capacity and possible service area of wastewater treatment facilities beyond the Metro Vision planning horizon.
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Chapter 2: Summary of Policy Statements
The Board of the Denver Regional Council of Governments has developed a set of over-arching policies in the Clean Water Plan. This chapter summarizes the major policy statements found in various chapters. Regional goal/connection to the Metro Vision Plan (Chapter 1) DRCOG’s regional water quality goal is to restore and maintain the chemical and physical integrity of the region’s waters to ensure clean water for residents and a balanced, healthy ecological community. DRCOG established six water quality policies in the Metro Vision Plan. These six policies are listed in the Introduction section. Stream standards and classifications (Chapter 4) In order to comply with the federal Clean Water Act, the Water Quality Control Commission (WQCC) develops standards, classifications, and antidegradation designations designed to protect the beneficial uses of water bodies throughout the DRCOG region. DRCOG’s policy is to support appropriate stream classifications, standards and antidegradation measures that best achieve the regional water quality goal. Impaired stream segments (Chapter 4) Section 303(d) of the Clean Water Act requires states to prepare and submit a report biennially to the EPA listing waters which do not meet water quality standards based on the established criteria (water quality-limited segments or impaired stream segments). It is DRCOG policy that the identification of impaired stream segments is an important step in the water quality planning process. DRCOG will work with the state and other entities in the region to identify impaired segments and address the issues causing such impairments.
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Chapter 2
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Stormwater and nonpoint pollution source (NPS) management policy (Chapter 5) DRCOG, in coordination with the Urban Drainage and Flood Control District, acts in an advisory capacity to permitted municipalities and counties. Recognizing that stormwater is a significant source of pollution, it is the policy of the DRCOG Board to facilitate regional partnerships in addressing stormwater pollution management and support innovative stormwater management practices. DRCOG’s policy statement regarding stormwater also holds for nonpoint sources: DRCOG will facilitate regional partnerships in addressing nonpoint source pollutants and support innovative NPS management practices. The DRCOG Board, through the Metro Vision 2035 Regional Transportation Plan, recognizes that transportation infrastructure contributes large quantities of nonpoint source pollution to watersheds throughout the DRCOG region. The Clean Water Plan therefore establishes that it is DRCOG policy to improve stormwater management practices for regional transportation systems through the local implementation of “green infrastructure” design, construction and maintenance approaches. Wastewater quality infrastructure planning goals and policies (Chapter 6) DRCOG’s goal in reviewing facilities is to ensure reasonable, feasible and economical wastewater service. The following policies guide DRCOG with regards to wastewater treatment systems: 1. Service areas for wastewater facilities will be consistent with future urbanized and some non-urbanized areas, as identified in the Metro Vision Plan. 2. DRCOG will review facility utility plans to ensure regional consistency. The Metro Vision Plan assessment process is used to review new wastewater treatment facilities and to incorporate changes into the Clean Water Plan. 3. Wastewater utility plans should show alternative projections and flows for WUSAs that are within 15 percent of the regional projections. Projections that differ by more than 15 percent will not be recognized in the Clean Water Plan without additional site-specific justification such as historical data and trends. 4. Facility consolidation should be addressed in the utility planning process and the decision should be based on economics, operation and management structure, water quality impacts, physical constraints and water rights.
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Biosolids (Chapter 6) The DRCOG Board recognizes and supports the economic and environmental benefits of biosolids reuse. The Board supports the beneficial use of biosolids unless doing so poses a threat to human health or the environment. Critical environmental resources (Chapter 7) Wetlands, riparian corridors, and groundwater aquifers are important elements of the region’s water resources. DRCOG has adopted policies to help retain and restore these important environmental elements. 1. Wetlands: DRCOG’s policy is no net loss of wetland functions within the DRCOG region. Development within a designated or delineated wetland should occur only when no other practical alternative exists. Wetland mitigation should consist of replacement of wetlands of the same type and function in order to maintain net wetland functions. 2. Riparian corridors: Riparian zones are important natural resources that provide multiple benefits. DRCOG supports the protection, enhancement and restoration of riparian zones throughout the DRCOG region. 3. Groundwater aquifers: Long-range management plans must consider groundwater quality. Activities which have the potential to adversely affect groundwater resources need to be properly managed. Groundwater recharge zones must be protected from water quality degradation. 4. Land use and water quality: Land use management must be considered in devising a water quality management strategy for a watershed.
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Watershed approach (Chapter 8) The goal of the DRCOG watershed protection approach is to apply an integrated, holistic strategy to protect or attain established beneficial uses of waters within regional watersheds, including protection of human health, aquatic ecosystems, and recreational uses.
Chapter 2
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Chapter 3: Clean Water Plan Implementation
DRCOG’s responsibilities The role of the regional planning agencies and areawide water quality management plans is to ensure that information for water quality decisions is adequate and up-todate and that local agencies follow through on designated projects. Federal and state statutes define DRCOG’s role in regional water quality planning: 1. Produce an areawide water quality management plan (the Clean Water Plan) which contains information on • Total maximum daily load (TMDL) studies and results • Effluent limits • Municipal and industrial wastewater treatment • Nonpoint source management and control • Residual waste • Site location approvals • Agriculture and silviculture • Mining • Energy development • Construction • Stormwater • Dredge and fill • Basin plans • Groundwater
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The DRCOG Board views regional water quality planning as a collaborative process involving all stakeholders— local governments, special districts, state and federal agencies in the Denver region all working together to protect, maintain and restore regional water quality. This chapter describes the roles and responsibilities of DRCOG, the regulatory agencies, management agencies, and the Water Quality Advisory Committee (WQAC). It also describes the Clean Water Plan assessment process.
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2. Set priorities and identify local needs for improving or constructing wastewater treatment facilities, as required by section 208(d) of the Clean Water Act. 3. Provide continuous water quality planning consistent with related areawide development planning efforts for a minimum 20-year planning period. Identify the social, economic and environmental costs and benefits of implementing regional water quality plans. 4. Produce reports, and review reports from local management agencies, on progress toward meeting the goals of the federal Clean Water Act and the State Water Quality Control Act. 5. Provide coordination among local agencies in implementing recommendations contained in the Clean Water Plan. Monitor and evaluate water quality and implementation activities and progress of designated agencies. Encourage corrective action by local groups and agencies. 6. Evaluate and recommend appropriate plans related to nonpoint source and stormwater management planning, including promotion of low-impact development (LID) practices and periodic review of best management practices. 7. In concert with local management agencies, recommend revisions to water quality standards and stream classifications where appropriate. 8. Review discharge permit applications (both new and renewal permits) to assure that discharges to a stream segment are treated in accordance with the approved plan, as required by section 208(d) of the federal Clean Water Act. 9. As requested, assist designated management agencies with review of site location approvals to assure consistency with approved water quality management plans and policies. Water Quality Advisory Committee responsibilities The Water Quality Advisory Committee (WQAC) advises the DRCOG Board of Directors on water quality issues and provides a regional water quality forum. A subcommittee -- the Wastewater Utility Plan Review Team -- assists the committee by performing technical reviews of wastewater utility plans and site location approval requests. Additional information regarding the committee’s membership and responsibilities is contained in the DRCOG Committee Policy Guidelines and Descriptions document. Regulatory agency responsibilities The WQCC develops the policies and rules for water quality management. The WQCC adopts water body uses, classifications, standards and antidegradation designations to protect and improve water quality in streams, rivers and lakes. The Water Quality Control Division (WQCD) issues appropriate permits and enforces water quality management rules established by the WQCC. WQCD leads efforts in water quality monitoring, protection and restoration. WQCD manages the Colorado Discharge Permit System (CDPS).
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Management Agency Roles and Responsibilities Management agencies are designated by the Governor in consultation with the 208 planning agency. According to Section 208 of the federal Clean Water Act, management agencies have the following nine authorities and responsibilities: 1. Implement policies of the areawide waste management treatment plan. 2. Effectively manage wastewater treatment through the oversight of operating agencies. 3. Accept and utilize grants, loans, and funds from other sources for water quality management purposes. 4. Raise revenues, including the assessment of appropriate fees and charges. 5. Incur short- and long-term indebtedness. 6. Assure implementation of the water quality management plan. 7. Where applicable, accept industrial wastewater for treatment and manage pretreatment programs. 8. Refuse to accept wastes from discharges not in conformance with the plan 9. Either directly or by contract, construct new works and operate and maintain existing works as required. In addition to these federally defined roles, the Governor may assign the following roles to management agencies (with their approval): • Review and submit any proposed amendments to the Clean Water Plan from their area of responsibility. • Review and comment on site location approval applications. • Provide input to the areawide water quality management program at DRCOG. DRCOG has identified several types of management agencies. The initial focus of the Clean Water Act was to identify point source management agencies; however, managing water quality requires that agencies deal with more than just point sources. Therefore, additional types of management agencies for nonpoint sources and stormwater have been defined. In each case, the management agency’s role is the implementation of the Clean Water Plan. Table 1 at the end of this chapter details management agency types and areas of responsibility. Water quality areas requiring management agencies All geographic areas within the nine-county DRCOG planning region have a designated management agency or set of management agencies. The same geographic area may have a point source management agency and a different nonpoint source management agency; however, cities and counties typically handle both sources. Areas within the DRCOG watersheds that are beyond the nine-county planning region can have management agencies listed in the Clean Water Plan, but are not bound by the plan. DRCOG has agreements with the North Front Range Water Quality Planning Association and the Pikes Peak Area Council of Governments to allow for joint recognition of management agencies within overlapping geographies.
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Chapter 3
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Preferences for management agency designation Watershed associations are the preferred water quality management agencies, since they can address all sources – point, nonpoint and stormwater (a specific type of point source). However, such associations may not have the full set of authorities outlined in the Clean Water Act. The association should be structured so that it includes members with the authority and ability to carry out the responsibilities for the areas within their land use jurisdiction. If a watershed association does not exist, other entities such as general purpose governments or special districts can be named as the management agency. The hierarchy of management agencies in overlapping geographies: 1. Watershed associations (responsible for point, nonpoint sources); 2. Special districts with multiple jurisdictions (responsible for point, nonpoint, stormwater) 3. General purpose local governments – cities and towns (responsible for point, nonpoint sources) 4. General purpose local governments – counties (responsible for point, nonpoint sources) 5. General purpose governments – counties (responsible for nonpoint, onsite systems or stormwater) 6. Special districts (responsible for point sources, nonpoint, stormwater) 7. Regional agencies (responsible for nonpoint sources) Required elements of areawide water quality plans The state determines elements of the Clean Water Plan that the DRCOG Board needs to update on a regular basis.1 These elements are: 1. Engineering and financial planning for expansion of municipal wastewater treatment works whenever throughput and treatment reaches 80 percent of design capacity; construction of municipal treatment works expansion whenever throughput and treatment reaches 95 percent of design capacity. The management plan shall identify the existing throughput and treatment, design capacity, and dates that the facility is expected to reach 80-95 percent of design capacity. 2. Capital purchases and construction programs for wastewater treatment plants that result in a change in degree, method of treatment or an increase in capacity. These needs, covering a minimum period of five years, must be identified in the management plan and supported by population projections, degree of treatment requirements, and facility timing criteria. New facilities must also be consistent with the service area, location, and capacity identified in the management plan. The plan must identify regional priorities for facility construction, improvement, or expansion.
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These elements are identified in the Colorado Water Quality Management and Drinking Water Protection Handbook (WQCC Policy #98-2).
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3. The location of existing and proposed wastewater treatment facilities. The plan will indicate the stream segment into which discharge is expected to occur. Stream segments will be consistent with segments contained in the prevailing state stream classifications. 4. The capacity of each sewage treatment facility based upon design criteria and operator proficiency, and the maximum daily wastewater flow and constituent loading which the facility can process while consistently meeting the effluent limits of discharged waters. The plan will identify the allowable organic and/or hydraulic throughput of the plant for existing conditions as well as projected needs. 5. Population projections for the management plan are based on state figures. 6. The plan defines the service area as the area for which the wastewater treatment plant will provide service when the facility reaches design capacity. It must be consistent with the 20-year service area contained in an adopted local master plan, and will be consistent with an adopted regional plan. 7. The plan identifies prevailing stream classifications and regulations for the level of treatment for existing and proposed facilities. 8. The plan must identify the social, environmental and economic impacts of implementation, in addition to tangible and intangible benefits for individual entities 9. Water quality management plans may also identify special permit requirements. The major factors in permit conditions for a municipality are determined by effluent limitations. These limitations are subject to the prevailing stream classifications and standards. 10. Management agencies will coordinate with the WQCD in determining the need for and completion of wasteload allocation studies by: 1) evaluating stream flow, water quality, existing and projected wastewater discharges; 2) recommending priorities for the conduct of detailed wasteload allocation studies; 3) making suggestions in regard to actual conduct of such studies, including institutional and financial ar rangements for carrying out the studies; and 4) recommending the most politically acceptable means for allocating wasteloads among multiple dischargers, where appropriate. 11. Nonpoint source information should be updated as new information becomes available either through wasteload allocation studies, stream sampling projects, or municipal control programs. 12. The designated planning agency is responsible for reviewing and evaluating the performance of each designated management agency within its planning area, and resubmitting and recommending each management agency at the time of formal updates.
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Chapter 3
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Clean Water Plan amendment process The amendment process for the Clean Water Plan begins with the Metro Vision Plan assessment process. The Metro Vision Plan assessment process provides the opportunity for local government members and designated management agencies to request changes to the Metro Vision Plan, including the Clean Water Plan portion. When the DRCOG Board takes final action on the Metro Vision Plan, the approved changes are incorporated into the Clean Water Plan. A proposed amendment to the Clean Water Plan should clearly define which elements of each plan are to be amended. Proposed changes can include: • Facility location • Service areas through the planning horizon • Sizing and staging of a treatment facility over the planning period • Level of treatment required to meet adopted stream standards • Alternative methods of treatment and disposal evaluated • Identification of the designated management agency for a facility Once a proposed amendment is received, DRCOG staff will inform all affected agencies and prepares a staff analysis of the request. Both the DRCOG staff analysis of the amendment request and management agency recommendations are forwarded to the WQAC for review. WQAC can recommend that the DRCOG Board of Directors approve, conditionally approve or deny the request. Before taking final action on the request, DRCOG will conduct a public hearing that allows concerned and affected parties the opportunity to address the amendment. The Board considers and takes action on the request after the public hearing. Approved amendments are incorporated into the Clean Water Plan and the Metro Vision Plan.
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The amended Clean Water Plan is forwarded to the WQCD for review. The WQCD will determine if the amendment is minor or major. Minor changes are agreed upon by the management agency, the planning agency and the WQCD. Amendments are considered minor if they do not significantly impact water quality planning. Major amendments warrant consideration by the WQCC and are subject to state public hearing processes. Major amendments that require specific action by the Commission include: • Changes in planning or management agency designation, • Changes in the regional population as agreed to in the state/regional disaggregation process, • Changes that are likely to engender regional public controversy, or • More than two state agencies express a strong interest in the amendment.
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Table 1 : Designated Management Agencies
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Table 1 : Designated Management Agencies (continued)
Notes
1. Point source management agencies are listed by the watershed in which the treatment plant is located. Service areas and management agency responsibilities may extend into more than one watershed. 2. The cities of Littleton and Englewood jointly manage a single treatment plant. Each city carries out other management agency responsibilities for their portion of the service area. 3. The Metro Wastewater Reclamation District has both direct and indirect connectors. Its management agency responsibilities extend over both types of connectors for its entire service area. 4. General purpose governments include cities and counties.
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Chapter 4: Regional Water Quality Assessment
Background: Use classifications and standards The federal Clean Water Act requires every state to report biennially the status of its water quality efforts. The report, referred to in Section 305(b) of the Act, details the status of the state’s water quality and water quality management programs. In order to compile these reports, federal and state regulations mandate assessment strategies that provide valuable information on the status of the region’s rivers, streams and water bodies. The Water Quality Control Commission assigns use classifications to all water bodies based on input from the Water Quality Control Division. The state defines the following use classifications: recreation, aquatic life, agriculture, water supply and wetlands. The state bases its classifications on water quality information, biological information, direct observation and best professional judgment for both conventional pollutants and toxic pollutants. To protect a water body’s use classification, WQCD develops both narrative and numeric standards that must be met. Narrative standards may be assigned by the Commission to apply to a specific state water where numeric criteria are not required under federal law. Narrative standards will be assigned based on the evidence presented at the classification and numeric standards-setting hearings. Numeric water quality standards are the maximum acceptable concentrations of specific pollutants in water bodies. These standards are established by the U.S. Environmental Protection Agency. Alternately, the state can adopt standards based on site- specific studies. In addition to use classifications and standards, Colorado has adopted antidegradation designations to protect classified uses for selected water bodies. Local governments may also recommend changes to standards, classifications, and antidegradation designations based on site-specific information.
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DRCOG policy on classifications and standards Since the WQCC adopts standards, classifications and antidegradation designations for streams and rivers, it is DRCOG’s policy to support appropriate stream classifications, standards and antidegradation measures that best achieve the regional water quality goal. To meet this policy, DRCOG will: • Work with the WQCD and DRCOG watershed groups to identify information and resources needed to determine appropriate uses • Review EPA and WQCD recommendations on standards and antidegradation designations for consistency with regional goals • Support watershed efforts to define site-specific standards • Testify before the WQCC on proposed changes to classifications, standards, or antidegradation designations regarding the consistency of the proposals with regional goals Processes to change designations The WQCC uses its triennial review and rulemaking hearing processes to revise stream standards, classifications and antidegradation designations. The triennial review is a public hearing conducted by the WQCC to receive information concerning proposed revisions. DRCOG recognizes two processes to request changes to standards and classifications. 1. Management agencies in the region may forward recommended changes to the Water Quality Advisory Committee (WQAC). The advisory committee has three options. The WQAC can fully accept, conditionally accept, or return these recommendations to the appropriate stakeholder group for further consideration. The advisory committee will submit fully approved and conditionally approved recommendations to the DRCOG Board of Directors through the Metro Vision Plan process or by special action when necessary. Following Board action, the Board will submit its position on recommended changes to the WQCD for review and the WQCC for action. 2. A person or group may request a separate rulemaking hearing before the WQCC. When a rulemaking hearing is scheduled, the party requesting the hearing is asked to submit relevant information to DRCOG so the agency may review it before the scheduled hearing. If necessary, final action or policy direction may be provided by the DRCOG Board of Directors. Impaired stream segments Section 303(d) of the Clean Water Act requires states to prepare and submit a report biennially to the EPA listing waters that do not meet water quality standards. This list consists of those waters for which technology-based effluent limitations and other required controls are not stringent enough to achieve water quality standards. These segments may require further monitoring or analysis to ensure they comply with water quality standards.
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In assessing whether a stream segment is impaired, the WQCD uses the following guidance: • Fully supporting all uses • Some uses have been assessed and all uses assessed fully support the designated uses • Not assessed for any uses
• TMDL (total maximum daily load) completed. May be supporting or not assessed and waiting for future monitoring to determine use support • Water is impaired, but a TMDL is not needed because other mechanisms are expected to result in Water Quality Standards in a reasonable amount of time • A use is impaired, but the impairment is not caused by a pollutant • Placed on Colorado’s 303(d) list; no TMDL has been completed DRCOG policy on identification of impaired stream segments It is DRCOG policy that the identification of impaired stream segments is an important step in the water quality planning process. DRCOG will work with the state and all entities in the region to identify impaired segments and address the issues causing such impairments. To meet this policy DRCOG will: 1. Support the relevant agencies in developing collaborative monitoring programs that will produce sufficient and reliable biological, chemical and physical data to support the efforts of WQCD. 2. Work with watershed groups to identify water quality trends that may point to future impairment of segments and develop early action programs to reverse such trends, if possible. 3. Work with its members, the state and watershed groups to secure funding for water quality assessment programs. 4. Review any proposed additions to the 303(d) list for the region and present recommendations of DRCOG advisory groups and members regarding such proposals to the state agencies through both formal and informal processes. 5. Work with its watershed groups to develop the plans needed to address any segments identified in the region as impaired. These plans will be summarized in the appropriate appendices to the Clean Water Plan. The state’s current 303(d) list can be found at: http://www.cdphe.state.co.us/wq/ Assessment/TMDL/303dlists.html Total Maximum Daily Loads (TMDLs) A TMDL is a mechanism to allocate pollutant loads on a segment/water body in a manner that allows the body to achieve water quality standards. Ideally, TMDLs develop allocations that will achieve attainment with applicable water quality standards. Section 303(d) (1) of the federal Clean Water Act requires states to identify water bodies that are water quality-limited. It also requires that states prioritize and target water bodies for TMDL processes and develop TMDL plans to achieve and maintain
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water quality standards. In Colorado, wasteload allocations developed through a TMDL process result in point source permit limits. Regulatory TMDL requirements TMDLs and individual water quality-based effluent limits must be included in water quality management plans to comply with sections 303(d) and 303(e) (3) (C) of the act and section 130.7 of CFR 40. The Colorado Water Quality Management and Drinking Water Protection Handbook (WQCC Policy #98-2) outlines the process to be used for TMDL preparation. It notes that the TMDL should be included in areawide water quality management plans, but also states: The Division has overall responsibility to complete TMDLs for all segments on the 303(d) list. However, the Division will rely upon local watershed groups and entities to participate and even develop TMDLs for their segments. TMDLs must ultimately be submitted to EPA for review and approval. Once a prioritized 303(d) list is finalized the Division’s principal responsibilities are: (1) to ensure that all completed TMDLs will be protective of water quality standards; and (2) to submit TMDLs to EPA for approval in accordance with the schedule for completion. While local entities have prepared studies for TMDLs, the majority of TMDLs in the DRCOG region are produced by WQCD staff. The WQCD process for preparing TMDLs is outlined below. TMDL process Every segment that the WQCC places on the 303(d) list will likely require a TMDL. The WQCC now calls the regulation adopting the 303(d) lists “Regulation 93: Water-Quality-Limited Segments Requiring TMDLs.” Within the 303(d) list, the WQCC prioritizes preparation of TMDLs as high, medium or low, based on consideration of severity of impairment to the use for the segment. The WQCD sets a goal of completing high priority TMDLs prior to the next biennial (303) (d) list. However, the WQCD recognizes that it may take more than two years to complete a TMDL because of the need for data collection or the development of a stakeholder process. Therefore, it is possible for a medium or low priority TMDL to be completed before segments with a high priority listing. After a TMDL has been determined, the WQCD, working with the watershed group or management agency, may develop an implementation plan for the stream segment. Such a plan may specify limits for point source discharges, establish permit requirements and recommend best management practices (BMPs). A segment may also be removed from the 303(d) list if the applicable standard is attained, if implementation of cleanup activities via an alternate means will result in attainment, if the original listing decision is shown to be in error, or if the standards have been changed.
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Challenges to the TMDL program While the Clean Water Act requires states to develop TMDLs for impaired water bodies, the federal government has not provided states with the resources to carry out many of the TMDL studies needed. The WQCD has acknowledged its limitations by setting priorities for the TMDLs identified in the 303(d) list. Even with adequate funding for the development of the identified TMDLs, the program does not provide mechanisms to enforce load and wasteload allocations except through existing regulatory programs. Relationship to the Clean Water Plan Once the WQCD has published a TMDL for public comment, DRCOG will review the report for consistency with the Clean Water Plan. This will include the growth and development assumptions, the impacts on point sources identified in the Clean Water Plan, and the feasibility of achieving the nonpoint and stormwater limits. If the impacts on point sources are significant, DRCOG may request that the affected management agencies prepare updates to Wastewater Utility Plans to address the necessary upgrades. Following EPA approval of a TMDL, DRCOG will incorporate findings of the TMDL into the appropriate Technical Appendices of the Clean Water Plan. If the TMDL causes changes to the location or service areas of any point sources, DRCOG will consider amendments to the Clean Water Plan during the next regular assessment cycle.
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Chapter 5: Stormwater and Nonpoint Source Managment
DRCOG stormwater management policy According to the State, the Clean Water Plan should accomplish the following:
“The plan should update nonpoint source and stormwater information of regional interest as it becomes available either through wasteload allocation studies, stream sampling projects, municipal control programs, or stormwater permit programs. The plan may identify nonpoint source elements, priority watersheds, best management practices, watershed restoration strategies, stormwater management programs and other waterside-oriented information.” DRCOG, in coordination with the Urban Drainage and Flood Control District (UDFCD), acts in an advisory capacity to permitted municipalities. Accordingly, DRCOG policy on stormwater management is as follows: Recognizing that stormwater is a significant source of pollution, it is DRCOG policy to facilitate regional partnerships in addressing stormwater pollution management and support innovative stormwater management practices. To accomplish this, DRCOG will: • Facilitate information exchange between management agencies, state and local agencies and within regional water quality management organizations
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The Federal Clean Water Act requires 208 plans to address issues involved with stormwater and nonpoint source (NPS) pollution sources. Stormwater pollution (a point source) and NPS pollution both contribute significantly to water quality degradation. With continued urban growth and the emergence of new Stormwater/NPS management strategies, it is timely for DRCOG to approach the issue from a regional perspective and introduce a regional policy on stormwater management and NPS pollution control. This chapter includes DRCOG policy on stormwater and NPS pollution management.
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• Support UDFCD guidance for local communities with regard to selection of innovative Best Management Practices (BMP) and control techniques • Emphasize the reduction of runoff volume (quantity) as a key consideration in managing stormwater quality • Work with the UDFCD to ensure the Stormwater Criteria Manual Volume 3 four-step process is followed • Support Low Impact Development (LID) efforts used to manage stormwater • Catalog and make available information on established BMPs • Provide information to local communities in selection of stream restoration and management practices
The UDFCD Urban Storm Drainage Volume 3 Criteria Manual is the principal source for information on stormwater management. It highlights a four-step process: Step 1: Employ runoff reduction practices (BMPs) Step 2: Provide BMPs with Water Quality Capture Volume (WQCV) Step 3: Stabilize drainageways Step 4: Consider the need for industrial and commercial BMPs The structural and nonstructural best management practices for stormwater are listed in Volume 3. DRCOG supports these best management practices for stormwater and nonpoint source management. Nonpoint Source (NPS) management policy In addition to regulated stormwater, the region’s water quality is affected by numerous nonpoint pollution sources, which include non-regulated stormwater and agricultural practices. DRCOG’s policy statement regarding stormwater also holds for nonpoint sources: DRCOG will facilitate regional partnerships in addressing nonpoint source pollutants and support innovative NPS management practices. The action items outlined above apply to NPS management as well. Section 319 of the Clean Water Act recognizes the water quality impacts from nonpoint sources. This section requires states to assess the magnitude and pervasiveness of nonpoint source pollution. It further requires the development of a state management plan, including educational programs. The WQCD develops a statewide nonpoint source assessment report and has recommended management programs in conjunction with a Nonpoint Source Alliance. The alliance serves in an advisory capacity to assist the WQCD with the nonpoint source program. The WQCD and NPS alliance play a role in the continuing effort to identify nonpoint source issues in Colorado. The partners design programs to demonstrate BMPs and provide educational opportunities. The WQCD’s Colorado Nonpoint Source Management Program identified five goals reducing water quality impacts from urban and construction activities:
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1. Education of the general public in urban centers in the areas of: • Use and disposal of household waste products; • Application of fertilizers, pesticides, insecticides and similar products; • Landscape design and effective uses of vegetation toreduce small lot erosion; • Construction-related erosion control; and • Other urban runoff pollution prevention activities. 2. Education of water quality professionals in: • Development of BMP training programs, and educational materials, classroom curriculum and other teaching aids; • BMP guidance documentation; • Landscape design and effective uses of vegetation to reduce construction related erosion; and • Other construction-related erosion control and prevention programs. 3. Education of local governments and state decision makers in urban centers with an emphasis on control and prevention programs such as: • Regulatory programs directed at erosion control, zoning or other special regulations or ordinances; • Planning level identification of available control and prevention, long-term and near-term alternatives, and cost-effectiveness of alternatives; and • Urban design and development prevention programs. 4. Demonstration and evaluation of control and prevention practices and structures -- including stormwater practices or structures -- related to urban development or construction activities. 5. Development of categorical urban and construction best management practice guidance documents and manuals. For further information, the complete program can be found at http://www.cdphe. state.co.us/wq/nps/2000MgtProg.html. Stormwater and the Regional Transportation Plan: Green infrastructure policy Green infrastructure describes an approach to stormwater management that is costeffective and sustainable. Green infrastructure practices include rain gardens, porous pavements, green roofs, infiltration planters, trees and tree boxes, and directing rainwater for landscape irrigation (some are not currently allowed under Colorado water law). These methods increase the degree of stormwater infiltration and help mimic pre-development hydrology. The DRCOG Board, through the Metro Vision 2035 Regional Transportation Plan, recognizes that transportation infrastructure contributes large quantities of nonpoint source pollution to watersheds throughout the DRCOG region.
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Recognizing that stormwater from transportation infrastructure is a significant source of pollution, the Clean Water Plan establishes that it is DRCOG policy to improve stormwater management practices for regional transportation systems through the local implementation green infrastructure design, construction and maintenance approaches. To accomplish this, DRCOG will: • Track progress on EPA Green Infrastructure Action Strategy and work to bring these concepts into design of transportation projects. • Support local implementation of green infrastructure design, construction and maintenance approaches by providing timely and relevant information to all DRCOG members on the current state of the practice in green infrastructure approaches. • Recommend policies for the Transportation Improvement Program (TIP) Policy development process that reflect higher priority for mitigation of nonpoint source pollution and regional watershed impacts through local transportation improvement projects • Recommend policies for the TIP Policy development process that seek to address water quality challenges produced by highway and other transportation infrastructure with available DRCOG TIP funding Best Management Practices (BMPs) Stormwater and nonpoint source control best management practices – both structural and non-structural -- improve water quality in discharges from construction sites and in urban areas. BMPs fall into two categories: erosion control BMPs and urban stormwater BMPs. Erosion control practices can provide improved water quality in discharges from construction sites. Urban stormwater BMPs can reduce loads after the construction phase is complete (e.g., phosphorus and nitrate which stimulate aquatic weeds and algae). Stormwater BMPs are intended to enhance urban runoff and flood control practices with the goal of improving water quality. The BMP list requires periodic updating; it is recommended that this management program and its BMPs be reviewed at least every five years. The structural and nonstructural BMPs are described in the UDFCD Urban Storm Drainage Volume 3 Criteria Manual. This includes the most up-to-date control methods for stormwater and nonpoint source runoff. All of the nonstructural BMPs have an educational component. There is also a need for general education programs related to nonpoint source runoff, stormwater discharges and other urban runoff. Specific education programs need to be directed toward the construction industry in the DRCOG region and throughout Colorado. Sediment is one of the most prevalent nonpoint source runoff components associated with urban development and construction activities. Similar BMPs are applicable to both stormwater runoff in urban areas and construction site runoff. Stormwater permits in Colorado The National Pollutant Discharge Elimination System (NPDES) provisions define stormwater management regulation. In Colorado the WQCD administers the program as part of the Colorado Discharge Permit System (CDPS). The purpose of the program is to reduce pollutants discharged to waterways that originate from stormwater runoff. The National Pollutant Discharge Elimination System (NPDES) Stormwater Rules require all municipal separate
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storm sewer systems (MS4s) that are publicly owned or publicly operated conveyance systems to obtain discharge permits to prevent storm water runoff from washing harmful pollutants into local water bodies. There are three major objectives of the stormwater discharge permitting program: 1. Reduce pollutant loadings in municipal storm sewer discharges to the maximum extent practicable (MEP). 2. Eliminate illicit wastewater connections, illegal discharges and non-exempt nonstorm water discharges to municipal storm sewer systems. 3. Implement management programs that apply best available technology (BAT), best conventional pollutant control technology (BCT) and, where necessary, water-quality based controls directed at controlling industrial stormwater pollution. There are two kinds of stormwater permits, called Phase I and Phase II. Phase I is the NPDES permit coverage for three different sources: • medium and large municipal storm systems (MS4s), • construction activity disturbing five acres of land or greater, and • various categories of industrial activity. Phase II increases the scope of stormwater management coverage to sources not falling in the original three categories. However, features attributed to Phase II have also been in place for Phase I permits since 1996. Today, the differences between the two are minimal. The following communities and other entities within the South Platte Urban Watershed hold MS4 permits: Aurora, Denver and Lakewood are Phase I communities. Phase II includes: Adams County, Arapahoe County, Arvada, Brighton, Cherry Hills Village, Columbine Valley, Commerce City, Douglas County, Edgewater, Englewood, Federal Heights, Glendale, Golden, Greenwood Village, Jefferson County, Littleton, Lone Tree, Northglenn, Sheridan, Thornton, Westminster and Wheat Ridge. The WQCD has also issued stormwater permits under Phase II to several school districts and metropolitan districts that manage stormwater systems. Please see Chapter 8: Watersheds for a list of MS4 permit holders by watershed. The current MS4 permits require the permit holder to prepare a stormwater management plan. The basic requirements of a stormwater plan include the identification of six specific control measures to be applied to the ‘maximum extent possible.’ It must also identify measurable goals for those measures, describe an implementation schedule and define the responsibilities for implementation.
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The six control measures are: • public education and outreach, • public involvement, • illicit discharge detection-elimination, • construction site runoff control, • post-construction stormwater management, and • pollution prevention/housekeeping measures. The TMDL for E. coli on segment 14 is the first instance where the WQCD has identified stormwater management as necessary to meet the stream standards in the South Platte Urban watershed. Since E. coli is likely to be a problem in most urban streams, the stormwater agencies noted above should follow the segment 14 effort closely and be prepared to take similar steps. Extent of impervious surfaces One key indicator of the potential for water quality complications is the amount of impervious land in a watershed. Scientific literature suggests that a watershed where at least 12 percent of the land area is impervious will have water quality impacts. When the impervious area reaches 30 percent, the watershed will experience water quality problems. Table 2 provides the 2006 percent imperviousness for the 10 DRCOG watersheds. Only the South Platte Urban watershed has reached the 30 percent level, although the Big Dry Creek watershed is just below 30 percent. Both the Bear Creek and Cherry Creek watersheds are slightly above the 12 percent threshold and are addressing impacts to the reservoirs at the terminus of the watershed.
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Table 2 : Percentage of imperviousness in Denver region watersheds (2006)
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Chapter 6: Water Quality Infrastructure Planning
Water quality treatment infrastructure includes wastewater treatment plants, lift stations and collection systems. DRCOG, as the 208 management agency, plays a key role in the planning of water quality treatment infrastructure. This chapter explains that role, and documents the planning processes for domestic wastewater treatment facilities and industrial dischargers. It also addresses related issues including biosolids and onsite treatment systems.
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I. Domestic Wastewater Facility Planning A. Project review considerations
DRCOG’s goal in reviewing facilities is to ensure reasonable, feasible and economical wastewater service. DRCOG uses the following criteria to review proposed wastewater management projects within its planning region: • Consistency with the approved Clean Water Plan; • The extent to which the project demonstrates need; • The extent to which the project might be revised to increase its effectiveness or efficiency; • The extent to which the project contributes to the achievements of areawide objectives and priorities related to natural resources and economic and community development; • The extent to which the proposed project significantly affects the environment;
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• The extent to which the project contributes to more balanced settlement and delivery of services to all sectors of area population including minority groups; and • A decision by a collector/interceptor or treatment agency regarding capacity or other facility matters will be referred to all affected general-purpose governments. Size classifications The Clean Water Plan identifies two classifications of treatment facilities. Major facilities are defined as having a hydraulic capacity of over 50,000 gallons per day. This applies to both domestic wastewater treatment plants and industrial dischargers. The Clean Water Plan also identifies minor wastewater treatment facilities and documents their location, sizing and level of treatment. Minor facilities are defined as having a hydraulic capacity between 2,000 and 50,000 gallons per day. Mapping of minor and major wastewater treatment facilities is maintained in the Clean Water Plan Technical Appendices. Service areas The Clean Water Plan identifies two types of wastewater management service areas: Wastewater Utility Service Areas (WUSAs) and Clean Water Plan (CWP) planning areas. The WUSA is the area that will require service within the Metro Vision planning horizon (currently 2035). The CWP planning area includes the WUSA along with additional areas that may require service beyond the Metro Vision planning horizon. Municipal boundaries, legal boundaries of sanitation districts and hydrologic basin boundaries are used in determining service areas although service areas might not match legal boundaries. DRCOG requires service areas to be consistent with the Metro Vision Plan and local land use plans. Wastewater Utility Service Areas (WUSAs) The Clean Water Plan identifies WUSA boundaries for all wastewater facilities. “Major” WUSAs serve more than 200 residential units and maintain a design capacity of more than 50,000 gallons per day. “Minor” WUSAs serve fewer than 200 residential units and maintain a design capacity of less than 50,000 gallons per day, with no plans to increase capacity beyond that limit within the Metro Vision planning horizon. If the facility anticipates expansion within that timeframe, DRCOG considers it a major facility. WUSA for minor facilities do not necessarily need to be contiguous with the urbanized area established in the Metro Vision Plan. The WUSA includes only areas where provisions for wastewater service are legally established and WUSAs for different wastewater facilities may not overlap. Both major and minor WUSAs have active discharge permits, and the WUSA is based on the service area identified at the time the discharge permit is approved. Clean Water Plan amendments, site approvals and other approvals under the Clean Water Plan require a recognized WUSA.
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Urban development within the WUSA must have urban growth boundary/area (UGB/A) allocation consistent with the Metro Vision Plan, and all UGB/A areas must be included in a WUSA. If an existing developed area is identified during the utility planning process as urban but not within the UGB/A, DRCOG and the affected local government will need to amend the
UGB/A map to include this area. Likewise, an area within the UGB/A that is not within a WUSA should be reviewed by DRCOG and appropriate Management Agency to identify the facility that will provide wastewater service. For communities that have elected to use an urban growth area rather than a mapped boundary, DRCOG uses an “unofficial” UGB map to define the WUSA (see the Metro Vision Growth and Development Supplement for more information about urban growth area communities). This service area information is incorporated into the discharge permits of these jurisdictions and thereby becomes “official” from a state perspective. Once pipes are in the ground an area is considered wastewater serviceable, whether it is platted or not, and becomes part of the community’s committed area. Consequently, the area must be included in the WUSA, and the UGB/A, even if a community determines for some reason that it is no longer committed for development (e.g., plat approval is revoked or expires). Special exemptions include land development activities that are not considered urban but often require centralized wastewater service such as open space, small commercial developments, parks, truck stops, campgrounds, park toilets, golf course clubhouses, etc. WUSAs may also include semi-urban development, residential areas that have lot sizes between one and 10 acres. Although semi-urban development is usually served with on-site wastewater systems (as well as individual water supply wells), there are situations where centralized service may be appropriate. Utility plans should explicitly identify any semi-urban areas that are served or are planned to be served by a facility. CWP Planning Areas The CWP Planning Area encompasses the entire WUSA and may also include adjoining areas expected to require urban services beyond the Metro Vision planning horizon. DRCOG requires local land use agencies to confirm that the portion of the CWP planning area beyond the UGB/A is consistent with local comprehensive plans, master plans, or other long-range land use plans. A CWP planning area may include a future urban area that extends significantly beyond the UGB/A. In some cases, the CWP planning area may more closely represent the ultimate build-out anticipated within the wastewater service provider’s service area or hydrologic basin. The portion of the CWP planning area outside of the WUSA is not expected to require urban services until after the Metro Vision planning horizon. CWP planning area can be converted to WUSA through the DRCOG plan amendment process or through the flexibility provisions described in the Metro Vision Growth and Development Supplement. Centralized wastewater facilities may be uneconomical or otherwise impractical (e.g., due to water rights considerations) in non-urban areas. Non-urban areas may be designated as being permanently served by onsite or cluster treatment systems. Also,
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certain non-urban areas, such as open space, landfills and agricultural trusts may be designated as permanent non-service areas. Sometimes the CWP Planning Area may include areas that have not been annexed or otherwise included in the provider’s statutory service area. In such a case, the provider may not have legal jurisdiction over the property and other providers may be able to serve the property. For areas where the means for obtaining wastewater service are not firmly established, evaluation of service options shall include referral to the affected local land use entities. These entities shall address consistency with applicable intergovernmental agreements or other arrangements between the responsible local government and wastewater service providers. All affected Wastewater Utility Plans (WUPs) shall be amended to reflect the final service option, including changes to WUSA and CWP Planning Area boundaries. WUSA and CWP Planning Area forecasts DRCOG generates and maintains population and employment forecasts and wastewater flow estimates in five-year increments through the Metro Vision planning horizon. These forecasts, contained in the Technical Appendix, determine a facility’s capacity requirements for use in the site location approval process and to meet other regulatory requirements. DRCOG may recognize alternative population, employment and flow projections if they are within 15 percent of the regional projections, or if there is adequate site-specific justification. DRCOG does not forecast growth and development beyond the Metro Vision planning horizon and accordingly does not generate wastewater utility planning data for those portions of CWP Planning Areas that lie outside the WUSAs. Wastewater utility plans provide their own projections and flows for these areas which can also be used to size a wastewater facility in the site location approval process.
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B. Permitting process 1. New Facilities
Site location approvals As part of the state Water Quality Control Act, the appropriate operating agency must obtain site location approval before municipal treatment plants can be constructed or expanded, or before lift stations and major interceptor lines can be built. Local agencies and DRCOG review the applications. The state Water Quality Control Division recommends final action on the applications, subject to appeal, to the WQCC. In reviewing site location applications, under the WQCC’s Regulation 22, the WQCD must consider 1) the approved regional water quality management plan and local comprehensive plans; 2) whether the facility site will minimize potential water quality impacts, and 3) consolidation with other wastewater facilities.
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The Water Quality Control Commission encourages local governments to establish coordinated reviews for site location approvals. Wastewater Utility Plans A wastewater plan must be submitted prior to or concurrently with a site location application. A wastewater utility plan provides basic information for wastewater treatment works that will: 1. Meet the requirements of the site location approval regulations of the WQCC, 2. Provide information regarding total maximum daily loads (TMDL), wasteload allocations and/or other watershed planning efforts, 3. Provide information regarding effluent quality and discharge permits, and 4. Demonstrate that WUSA and CWP planning areas do not overlap. The primary goal of a wastewater utility plan is to demonstrate that reasonable, feasible and economical wastewater service can be provided to an area designated for urban development within the DRCOG watersheds. A utility plan should consider the water quality impact the treatment system will have on receiving waters, provide a strategy
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Regulation 22 further defines the site location application review criteria: That the existing treatment works will not be overloaded when connecting new lift stations or interceptors subject to site application requirements of sections 22.6 and 22.7; That the proposed treatment works is developed considering the local long-range comprehensive plans for the area as it affects water quality and the approved water quality management plans for the area; That the proposed treatment works can protect water supplies by meeting its discharge permit (where applicable), which is based on water quality standards and/or appropriate waste load allocation; That the proposed treatment works has been properly reviewed by all appropriate local, state, and federal government agencies and 208 planning agencies; That the proposed treatment works can be operated and managed at the proposed site location to minimize foreseeable potential adverse impacts on the public health, welfare, and safety, as related to wastewater treatment and/or water quality; That the applicant is capable of providing for adequate treatment works construction and operational management, including legal authority and financial capabilities, to meet its preliminary effluent limitations, where applicable, and minimize potential adverse impacts on water quality on a long-term basis; That the proposed treatment works be so located that it is not unnecessarily endangered by natural hazards; and That the objectives of other water quality regulations will not be adversely affected.
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for meeting all applicable water quality standards and classifications, and consider the potential impact a discharger may have on other dischargers. The minimum required components of utility plans include: infrastructure type and capacity, location/siting, level of treatment and effluent standards, WUSA and CWP planning areas, and management and financial considerations. Each wastewater utility plan will address the WUSA and CWP planning area for one or more existing or proposed wastewater treatment works. The Clean Water Plan requires that a wastewater utility plan evaluate opportunities for non-potable wastewater reuse. Further, it is DRCOG and state policy that facility consolidation be addressed. Further details of components required in utility plans are included in the Clean Water Plan Wastewater Utility Plan Guidance Document. Wastewater utility plans will be reviewed by WQAC for consistency with the Clean Water Plan. WQAC has three options in reviewing plans: • accept the utility plan, • accept conditionally, or • refer the plan back to the applicant/operating agency for additional information or action. Upon DRCOG Board approval, DRCOG provides a formal letter of approval to the WQCD. DRCOG will maintain a database on final utility plans and any supplemental documents. Discharge permits Following site location approval, a wastewater treatment plant must obtain a discharge permit from the WQCD prior to being placed into service and discharging to waters of the state. The Clean Water Act requires that all discharge permits for point sources be in conformance with the adopted water quality management plan. In Colorado, the WQCD approves discharge permits under regulations adopted by the WQCC. WQCC Regulation 61 requires that the WQCD notify the relevant 208 water quality planning agency (such as DRCOG) and solicit their comments on draft discharge permits (during the 30-day public notice period). DRCOG is not involved in the review of renewal permits. DRCOG will determine if information provided in the final permit is consistent with the Clean Water Plan. DRCOG notifies the WQCD of inconsistencies and provides supporting documentation.
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2. Existing facilities and other treatment works
Existing Facilities and Wastewater Utility Plan updates Operating agencies for existing wastewater treatment works should submit a Wastewater Utility Plan if they have not yet done so. Updates to wastewater utility plans will be considered for approval by the UPRT, WQAC and DRCOG board. Utility plans approved by WQAC will need to be amended because of facility upgrades or other changes. Additional update or amendment documents can be appended to the original utility plan, after acceptance, without re-issuing the final utility plan.
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Lift Stations and Interceptor Works Site approvals for lift stations or interceptor works are also considered by the DRCOG board but do not involve wastewater utility plans or discharge permits. A lift station can be documented by incorporation into an existing WUP; if it is privately operated, it will not be documented in any WUP and the applicant must submit a complete document describing the maintenance and operating procedures for the lift station.
II. Industrial Dischargers
The state’s site location approval process for domestic wastewater treatment facilities provides DRCOG and other local agencies with sufficient notice and time for their review and comment on new applications. However, industrial dischargers are not subject to the same site location approval process, and early notification does not necessarily take place. The federal Clean Water Act states that “no permit under Section 402 of this Act shall be issued for a point source which is in conflict with a plan approved pursuant to subsection (b) of this section 208(e)” without distinction as to the industrial or municipal nature of the discharge permit. The WQCD issues permits in a number of different categories. Major dischargers, both domestic and industrial, are typically issued individual permits. However, many industries have general permits which cover multiple wastewater treatment facilities that operate under similar conditions and regulatory requirements. General permits provide the WQCD with an effective tool to manage the numerous discharges that occur under the industrial permitting program. Including industrial dischargers in the Clean Water Plan The inclusion of industrial dischargers in the Plan should follow a hierarchy similar to that of minor and major domestic wastewater facilities: • Major industrial facilities: Full inclusion into the CWP with DRCOG Board of Directors’ action Facilities that require individual permits or water treatment plant wastewater dischargers (general permits); having a capacity greater than 50,000 gallons per day or discharging to a stream segment with a TMDL. • Minor industrial facilities: Partial inclusion in the CWP with DRCOG Board of Directors’ action (shown in technical appendices but not in CWP Chapter 8) Facilities that require individual permits and water treatment plant wastewater dischargers (general permit); having a capacity less than 50,000 gallons per day but more than 2,000 gallons per day or discharging to a segment with a TMDL. Two additional types of industrial dischargers would be included in the Clean Water Plan: Aquatic animal production and groundwater remediation, when discharges are greater than 2,000 gallons per day or to a segment with a TMDL.
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Planning process for industrial dischargers Existing major facilities (identified by WQCD records) have been added to the appropriate watershed maps and are shown on figure 3. The Clean Water Plan’s technical appendices will list the industrial dischargers (both major and minor) with their permitted capacities. If they are affected by the wasteload allocation in that watershed, the allowable limit will be described. For new industrial dischargers, DRCOG intends to enter into a Memorandum of Understanding with the permit section of the WQCD, which will provide DRCOG with copies of the permit applications for new or expanded facilities meeting the criteria listed above. In watersheds having a designated watershed authority, the authority will review the application and provide comments to DRCOG staff. In other watersheds, the general purpose local government in which the discharge occurs will review the application and provide comments. If water quality issues are identified regarding the proposed industrial discharger, DRCOG will work with the applicant to address the issues. DRCOG staff will provide a summary of the water quality issues to the WQAC and DRCOG Board of Directors. If there are unresolved water quality issues, DRCOG will provide comments to the WQCD concerning the proposed permit. DRCOG will provide these comments within the timeframes of the permitting process as defined by the WQCD, to the maximum extent possible. Once the WQCD issues a permit to an industrial discharger, DRCOG will include that facility in the Clean Water Plan (for major facilities) and the appropriate watershed technical appendix.
III. Other wastewater treatment infrastructure issues
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Onsite Treatment Systems It is not always practical to serve certain areas with centralized wastewater treatment facilities. The wastewater service for such areas might be achieved by using onsite or cluster wastewater treatment systems: 1. Onsite individual wastewater treatment using an onsite systems tank and drainage field system or alternate technology; 2. Cluster wastewater treatment systems which connect multiple households to a small treatment system using conventional or alternative technologies; 3. A centralized wastewater treatment facility to service the entire development community. Local health departments, with state oversight, regulate onsite system and individual disposal systems under 2,000 gallons per day. These smaller systems are not identified in the Clean Water Plan. Systems over 2,000 gallons per day are subject to the state site location approval and DRCOG approval processes. Accordingly, all onsite treatment systems having a capacity of greater than 2,000 gallons per day shall have a wastewater utility plan and be identified in the technical appendices of the Clean Water Plan as minor wastewater
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treatment facilities. Where feasible, areas served by onsite system and individual disposal systems will be encouraged to connect to a centralized treatment system which maximizes use of the system and avoids groundwater contamination resulting from onsite system and individual disposal system failure. Biosolids The federal Clean Water Act directed the EPA to develop regulations for the use and disposal of sewage sludge, also known as biosolids. These regulations include facility siting requirements, uses, operating procedures, and allowable contaminant concentrations for different sludge disposal and beneficial use methods. One result of increasingly stringent effluent standards and treatment requirements is that more biosolids are created after being removed from the wastewater flow during the treatment process. Predominantly organic, biosolids are nutrient-rich residual material, and may be used as a soil amendment when used in compliance with state and federal regulations. Colorado’s biosolids regulations (Colorado Department of Public Health and Environment Biosolids Regulation No. 64) define biosolids as the accumulated, treated, residual product resulting from a domestic wastewater treatment works. DRCOG policy on biosolids DRCOG recognizes the economic and environmental benefits of recycling biosolids. DRCOG supports any biosolids disposal practice that attempts to beneficially reuse this resource, unless doing so poses an unacceptable threat to human health or the environment. National pre-treatment program The U.S. Congress created the National Pretreatment Program in 1972 to protect the nation’s wastewater treatment facilities and waterways from discharges of toxic and other pollutants. The term pretreatment refers to the requirement that certain identified industries discharging must treat their wastewater before discharging it to a municipal sewer system. The three objectives of the National Pretreatment Program are: 1. Protect municipal wastewater treatment systems from damage or interference caused by industrial wastes; 2. Protect the nation’s waters from industrial pollutants which may pass through municipal wastewater treatment systems untreated or undertreated; and 3. Allow for the beneficial use of wastewater biosolids as soil conditioners and fertilizers by preventing excessive contamination by industrial pollution.
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The U.S. EPA administers the National Pretreatment Program under the General Pretreatment Regulations, first adopted in 1978. These regulations, as amended in 1981 and 1988, set forth specific requirements that both wastewater treatment facilities and industries must comply with to reduce industrial pollutant discharges. The General Pretreatment Regulations require that any wastewater treatment facility that is designed to treat at least five million gallons of wastewater per day, or that receives significant discharges from industrial sources, must develop a local pretreatment program conforming to EPA regulations.
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Chapter 7: Critical Environmental Resources
Overview Local governments and state and federal agencies have identified certain environmental resources as critical regional issues. This Chapter describes policies to address critical environmental resources. DRCOG is responsible for reviewing environmental assessments and other plans referred to DRCOG for review and comment. These reviews evaluate a proposed project for consistency with adopted policies and management plans identified in the Clean Water Plan. Additional regional environmental issues can be evaluated by the WQAC, the Metro Vision Issues Committee and the DRCOG Board for policy direction on an as-needed basis. This chapter describes policies and their rationale for wetlands, riparian corridors, groundwater aquifers, and addresses the connection between land use management and water quality. Regional policies for critical environmental resources Wetlands: DRCOG’s policy is no net loss of wetlands within the DRCOG region. Development within a designated or delineated wetland should occur only when no other alternative exists. Wetland mitigation should consist of replacement of wetlands of similar type and function that will at least maintain net wetland functions. Riparian Corridors: Riparian zones are important natural resources that provide multiple benefits. DRCOG supports the protection, enhancement and restoration of riparian zones throughout the Denver region. Groundwater Aquifers: Long-range management plans must consider groundwater quality. Activities which have the potential to adversely affect groundwater resources need to be properly managed. Groundwater recharge zones must be protected from water quality degradation. Land use and water quality: Land use management must be considered in devising a water quality management strategy for a watershed.
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Analyses of critical environmental resources Wetlands Wetlands are valuable regional resources which serve multiple beneficial functions. Properly managed wetlands • protect and improve groundwater and surface water quality, • help control flooding, • reduce or trap downstream migration of eroded sediments, • provide critical habitat for plants and animals, and • provide aesthetic features and recreation. Various federal, state and scientific assessments of wetlands have identified them as an endangered natural resource. As a result, wetlands protection is a significant federal issue and the U.S. EPA has required all states to include regulatory wetland protection in their water quality standards and classification systems. There are a variety of wetlands in the nine-county DRCOG region. Some of these wetlands are important wildlife habitats, while others are used to improve urban runoff water quality. The three essential characteristics of wetlands are hydrophytic vegetation, hydric soils and wetland hydrology. Wetlands are currently defined in the Clean Water Plan (based on the federal Clean Water Act) as: “Those areas that are inundated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances, do support a prevalence of vegetation typically adapted for life in a saturated soil condition.” There are specific federal statutes (sections 401 and 404 of the 1987 Clean Water Act amendments) which govern activities involving wetlands. These regulations control discharges into wetlands and placement of dredge or fill materials into wetlands. The Federal Manual for Identifying and Delineating Jurisdictional Wetlands provides the technical criteria, field indicators and methodology to determine whether an area is a wetland. Any scientific analysis of a wetland should be consistent with this manual. DRCOG supports the concept of wetlands protection and all DRCOG plans will recognize the value of wetlands as part of the planning process. In addition to the no net loss policy, DRCOG maintains the following position on wetlands: 1. DRCOG promotes the use of wetlands for water quality enhancement. Regionally significant wetlands are those which have documented water quality enhancement features, as determined by DRCOG. Local and regional agencies should protect regionally significant wetlands.
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2. DRCOG encourages the use of constructed wetlands for resource management purposes such as wastewater treatment, stormwater abatement and wildlife management.
3. Numeric and narrative water quality standards developed for surface waters may not apply to wetlands, if the wetland is not a tributary to an adjacent flowing stream. In many cases streams and wetlands may have different environments which support disparate plant and animal communities and process pollutants in different ways. 4. Narrative standards intended for water quality protection in wetlands are appro priate. Numeric standards should only be established on a site-specific basis where problems exist. 5. DRCOG only supports wetland water quality standards and classifications if they recognize the beneficial role wetlands have in processing urban stormwater. Riparian Corridors Riparian corridors are generally comprised of the unique vegetation, soils and life forms that are found adjacent to rivers, lakes and streams. Local governments, citizens, and community organizations across the region have expressed concern for protection and maintenance of riparian corridors because they: • suppress the effects of flooding by absorbing and deflecting peak flows; • maintain water quality by intercepting surface water flows and absorbing excess nutrients; • provide habitat for birds, mammals, fish and other forms of wildlife; and • provide aesthetic, recreational and educational benefits. Accordingly, it is DRCOG policy to take the following steps:
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1. Work with local governments to develop a set of criteria that defines the characteristics and functions of riparian zones. 2. Consider riparian resources in the siting process for all regional infrastructure including transportation and wastewater facilities. 3. Encourage consistency in state and/or federal review and regulatory processes regarding riparian zones. 4. Encourage local governments to develop public education programs or other non-regulatory approaches for implementation at a local level. Examples of non-regulatory programs include “adopt a river” programs and the purchase of riparian property. DRCOG will assist local governments in the development of public education programs. 5. Encourage local governments to adopt a riparian management program. Components of this program could include an inventory of riparian resources, identification of locally significant riparian zones and a riparian zone protection ordinance. DRCOG will assist local governments by developing a model management program and a model riparian ordinance.
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Groundwater Groundwater is an important source of agricultural and potable water for Colorado. There are many municipalities in the Denver region which rely on groundwater to meet their water needs. The Water Quality Control Commission (WQCC) adopted groundwater standards in 1987 with subsequent amendments. Groundwater quality in the Denver region is affected by waste disposal, urbanization, nonpoint runoff and agriculture. Waste disposal and agricultural practices have been the primary sources of groundwater contamination. Onsite system disposal has resulted in biological contamination of rural and other water supplies. Organic and metal pollutants and radiation from CERCLA sites have been identified in water wells at various locations in the metropolitan region in recent years. There are currently few programs to monitor groundwater quality away from these sites, except for public potable supply systems as required by the Colorado Department of Public Health and Environment (CDHPE).
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Chapter 8: Watersheds
Watersheds are defined by the geographic area of land that drains water to a shared destination. The Clean Water Plan uses a watershed approach to water quality management in the 10 mapped watersheds in the region. See Figure 3 for a map of the 10 watersheds. The goal of the DRCOG watershed protection approach is to apply an integrated, holistic strategy to protect or attain established beneficial uses of waters within regional watersheds, including protection of human health, aquatic ecosystems and recreational uses. This chapter contains a summary of each of the DRCOG region’s 10 watersheds. The summaries are divided into “watershed description” and “water quality management.” The former deals with physical and hydrological characteristics. The latter addresses governance and includes wastewater treatment facilities. More detailed information is contained in the Clean Water Plan Technical Appendices.
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Bear Creek Watershed
Watershed description The Bear Creek Watershed covers 236 square miles in Jefferson, Clear Creek and Park counties. The headwaters begin at the Continental Divide at an elevation of over 14,000 feet in the Mount Evans wilderness. From there, the watercourse flows east. DRCOG defines the downstream limit at Bear Creek Reservoir with the lower portion of Bear Creek part of the South Platte Urban watershed. Major tributaries to Bear Creek include Cub Creek and Turkey Creek. The U.S. Army Corps of Engineers built the Bear Creek Reservoir in 1982 as a flood control facility at the confluence of Bear and Turkey creeks. The City of Lakewood manages park facilities at the reservoir including non-motorized boating and fishing. The Bear Creek Watershed is primarily non-urban. National forests make up a large portion of the watershed. It includes Evergreen, Conifer and Genesee. Morrison and Lakewood are the only incorporated communities in the watershed. Denver-area urban development stretches into the Bear Creek Watershed next to the reservoir and along Turkey Creek, where the Willow Springs and Willow Brook subdivisions are located. About five percent of the watershed is in Park County, outside of the DRCOG planning area. This area is non-urban in character. Water quality management The Bear Creek Watershed Association is the designated water quality management agency for the Bear Creek Watershed. The association was formed through intergovernmental agreement in 1996. It is an active management agency, responsible for implementing the Bear Creek Reservoir control regulation. The association maintains a regular monitoring program in the reservoir and the watershed. The Water Quality Control Commission (WQCC) did not identify any segments in Bear Creek as use-impaired on the 2006 303(d) list. A Total Maximum Daily Load (TMDL) exists for Bear Creek. All dischargers in Bear Creek have wasteload allocations under the TMDL. The WQCC also placed Bear Creek Reservoir on the monitoring and evaluation list for dissolved oxygen. Please see the Bear Creek Technical Appendix for more information. Bear Creek Watershed currently has 15 permanent wastewater treatment facilities and one proposed facility. Table 4 lists current wastewater facility discharge permits and Figure 4 shows their location within the watershed. Of these 16 facilities, eight are major (capacities greater than 50,000 gallons per day).
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Table 3 : Bear Creek Watershed Wastewater Treatment Facilities
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Beebe Draw Watershed
Watershed description The Beebe Draw Watershed includes portions of three hydrologic watersheds: Beebe Draw, a portion of the Box Elder Creek Watershed, and a portion of the South Platte Watershed. The portions of this watershed that flow directly to the South Platte River are all located in Weld County, outside of the DRCOG water quality planning area. The Box Elder Creek watershed begins in Elbert County and flows north/northwest through Arapahoe, Adams and Weld counties until it reaches the South Platte River near Greeley. The portion of the Box Elder Watershed south of Denver International Airport (DIA) is included in the East Plains Watershed. The downstream portion, beginning at DIA, is included in the Beebe Draw Watershed. The Beebe Draw watershed is unique in its hydrology. No major stream channel flows through the watershed. Instead, a series of swales connected with irrigation canals generally flows from south to north. Barr Lake and Milton Reservoir are the watershed’s two prominent water bodies. Most of the watershed is covered by agricultural land uses. The watershed contains some of the most productive irrigated agricultural lands in the state of Colorado. Water quality management The Town of Lochbuie operates the only treatment facility located in the watershed and is the designated management agency. The Metro Wastewater Reclamation District provides service to DIA and is a designated management agency for its service area. The Metro District shares management agency responsibilities with the City of Aurora, which may have development in the upper reaches of the watershed in the future. Adams County serves as the management agency for minor facilities in the unincorporated portions of the watershed. The Water Quality Control Commission (WQCC) has designated the reservoirs within the watershed as impaired. Barr Lake and Milton Reservoirs are jointly listed for impairment because of high pH values. Horse Creek Reservoir, located in the Box Elder Creek Watershed at the northern border of Adams County, is also listed for pH, but with a low priority for preparation of a Total Maximum Daily Load (TMDL). While not a designated management agency, the Barr Lake and Milton Reservoir Watershed Association is preparing a pH TMDL and associated implementation plan to address the impairments. The study area for this effort includes both the Beebe Draw and South Platte Urban watersheds. As noted above, the Lochbuie facility is the only permitted municipal treatment plant in the DRCOG portion of the watershed. It serves both the town and the eastern portion of Brighton as shown in Figure 5. This figure and Table 5 include an industrial permit for the water treatment plant of the City of Brighton.
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Table 4 : Beebe Draw Watershed Wastewater Treatment Facilities
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Big Dry Creek Watershed
Watershed description The Big Dry Creek Watershed originates in unincorporated Jefferson County at the mouth of Coal Creek Canyon at an elevation of approximately 8,000 feet. The total drainage area is approximately 110 square miles. The headwaters area is located around 5 miles west of Rocky Flats Wildlife Refuge (formerly known as the Rocky Flats Environmental Technology Site or RFETS), 10 miles south of the City of Boulder and 10 miles west of the City of Westminster. The basin drains easterly from the headwaters across the Rocky Flats Wildlife Refuge. Below Standley Lake Reservoir, Big Dry Creek flows in a northeasterly direction approximately 33 miles through the City of Westminster, City and County of Broomfield, the city of Thornton, and Adams and Weld counties to its confluence with the South Platte River near Fort Lupton. The confluence marks the furthest downstream end of South Platte Segment 15. Colorado Boulevard roughly divides the watershed between urban and agricultural uses, with agricultural uses dominating the east side of Colorado Boulevard and urban uses dominating the west. Human modifications greatly influence the hydrology of Big Dry Creek. Standley Lake reservoir was the first large anthropogenic modification. Constructed in 1906, Standley Lake reservoir is an on-stream reservoir. Agricultural releases and stormwater runoff from urbanized areas increase flow intensity while discharges from wastewater treatment facilities increase the base flow. Agricultural diversions to multiple irrigation ditches and use of treated effluent for reuse purposes serve to reduce flows. Both Broomfield and Westminster are actively implementing water reuse programs that decrease the volume of wastewater that discharges to Big Dry Creek. The closing of RFETS in 2006 resulted in reduced impervious surface cover and site runoff. Water quality management Designated management agencies for the Big Dry Creek watershed include the City and County of Broomfield, the cities of Northglenn, Thornton and Westminster, and Adams and Jefferson counties. Weld County participates through the North Front Range Water Quality Planning Association. Water quality coordination in the watershed is conducted cooperatively via membership/participation in the Big Dry Creek Watershed Association. The Association conducts an extensive in-stream monitoring program aimed at determining aquatic life and habitat conditions. It also maintains a large water quality database. Other association activities include preparation of a watershed plan, public education and undertaking special studies of watershed issues identified by stakeholders. Prior to 2006, no streams segments in the Big Dry Creek Watershed were on either the state’s impaired 303(d) list or the monitoring and evaluation list. The WQCC placed segment 1 on the 303(d) list in 2006 for selenium and E. coli. In 2008, a site-specific selenium standard was adopted due to naturally elevated selenium concentrations in the watershed. Removal of the selenium listing is anticipated for the 2010 303(d) list. The segment remains on the 303(d) list for E. coli. The Association has conducted several studies to identify bacteria sources in the watershed. Studies to date suggest non-point sources of bacteria in open
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space and agricultural areas. Big Dry Creek may be subject to an E. coli TMDL in the future. In addition, as TMDLs are formulated for the middle South Platte River (i.e. Segment 15), dischargers to Big Dry Creek may be required to accept allocations of identified pollutants to protect downstream uses. Table 6 lists the three permitted wastewater treatment facilities in the Big Dry Creek Watershed. The Metropolitan Wastewater Reclamation District’s facility in the South Platte Urban Watershed serves portions of the watershed. Figure 6 depicts the location and service areas for these plants. Table 6 : Big Dry Creek Watershed Wastewater Treatment Facilities
In May 2005, the City and County of Broomfield completed the first phase of its wastewater treatment facility expansion, increasing the treatment capacity from 5.4 MGD to 8.0 MGD and adding 6 MGD of reclaimed wastewater treatment. The second phase, begun in October 2007, will increase the wastewater treatment expansion to 12 MGD. The phase 2 expansion is expected to be completed by the summer of 2011.
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Boulder/Saint Vrain Watershed
Watershed description The Boulder/St. Vrain Watershed covers nearly 1,188 square miles in Boulder, Gilpin, Jefferson, Broomfield and Weld counties. The upper reaches of the watershed are mountainous and include Rocky Mountain National Park, the Indian Peaks Wilderness Area and the Roosevelt National Forest. The headwaters begin at the Continental Divide at an elevation of nearly 14,000 feet in Boulder and Gilpin counties. The watercourse flows east and north to the confluence with the South Platte River below Fort Lupton at 4,900 feet elevation. The major cities in the watershed are Boulder and Longmont. The hydrology of the Boulder/St. Vrain watershed is unique in that it is subject to limited diversions from other watersheds. Trans-mountain water enters the watershed from the Northern Conservancy District, where it is used for irrigation and municipal water in the plains portion of the watershed. Gross Reservoir, an element of the Denver Water system, serves both as storage and a regulating facility for water diverted from the Fraser River near Winter Park through the Moffat Tunnel. Water quality management The designated management agencies in the Boulder/St. Vrain watershed are Boulder County, the cities of Boulder, Longmont, Louisville and Lafayette, and the towns of Erie, Lyons, Nederland and Superior. In the St. Vrain Creek portion of the watershed, the WQCC identified three segments as impaired. Impairments in segments in Upper Left Hand Creek and Little James Creek result from metals loadings. Impairments in Little James Creek are due to copper and lead, while Left Hand Creek impairments result from copper, zinc and pH. The WQCC listed a segment including all tributaries to St. Vrain Creek below Hygiene Road for levels of selenium. A segment of Dry Creek has E. coli impairments, according to the list. Of these segments, only Dry Creek has a high priority for a TMDL study. In the Boulder Creek portion of the watershed, the WQCC listed four segments as impaired. The WQCC listed a portion of Boulder Creek through the City of Boulder, a segment of Coal Creek, and Boulder Creek below the confluence of these two segments for E. coli. The Commission also listed Gamble Gulch, within one of the impaired segment 4a, for copper, zinc and pH levels. All of these segments are high priorities for TMDL efforts. The Boulder/St. Vrain Creek watershed currently has 22 permanent wastewater treatment facilities. Table 7 lists the current discharge permits and Figure 7 shows their location within the watershed. Of these 22, eleven are major facilities (with capacities over 50,000 gallons per day).
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Table 6 : Boulder/St. Vrain Creek Watershed Wastewater Treatment Facilities
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Chatfield Watershed
Watershed description The Chatfield Watershed encompasses approximately 483 square miles. It is defined as the area tributary to the South Platte River between the outlet of Strontia Springs Reservoir and the outlet of Chatfield Reservoir. The major hydrologic features in the Chatfield Watershed are Plum Creek, Deer Creek and Massey Draw. The headwaters of Plum Creek extend into El Paso County, but the majority of the watershed is in Douglas and Jefferson Counties. Chatfield Reservoir is a major watershed feature and the focus of most of the water quality discussions in the watershed. Below the reservoir, the South Platte River flows towards downtown Denver as part of the South Platte Urban Watershed. The area above Strontia Springs is in the Upper South Platte Watershed. Much of the Chatfield Watershed is national forest with limited opportunities for residential development. Douglas County has purchased significant portions of the non-mountainous areas as open space, including the Greenland and Cherokee Ranches. Urban development is concentrated in the Castle Rock and Roxborough Park areas. Water quality management The Chatfield Watershed Authority is the designated water quality management agency for the Chatfield Watershed. Members have jointly signed the Chatfield Watershed Authority Memorandum of Understanding. The Authority has the power under Colorado law to develop, recommend and adopt provisions for water quality management within the Chatfield Watershed consistent with the Clean Water Plan. No water bodies in the Chatfield Watershed are on the State’s 303(d) list of impaired stream segments. Spring Creek and Bear Creek, on a segment of West Plum Creek, are on the state’s monitoring and evaluation list because of concerns about aquatic life. Chatfield Reservoir has an adopted Total Maximum Annual Load (TMAL) and much of the water quality management planning in the watershed is focused on implementing this TMAL. Figure 8 indicates the locations of the permanent wastewater treatment facilities in this watershed. These facilities are also listed in Table 8. It should also be noted that portions of the watershed are served by facilities that are located outside of the watershed. Both the Littleton/ Englewood plant and the Centennial plant serve areas in the northern portion of the watershed, but discharge into the South Platte Urban Watershed.
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Table 7 : Chatfield Watershed Wastewater Treatment Facilities
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Figure 7 : Chatfield Watershed
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Wastewater Utility Service Areas (WUSA) and Clean Water Plan (CWP) Planning Areas 1 - Littleton/Englewood 2 - Centennial 3 - Sterling Ranch 4 - South Santa Fe 5 - Town of Louviers 6 - Roxborough State Park 7 - Plum Creek Wastewater Authority 8 - Jackson Creek Metropolitan District 9 - Perry Park West 10 - Perry Park East 11 - Town of Larkspur 12 - Ponderosa Retreat and Conference Ctr
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SOURCE DATA: Road Network - TeleAtlas, Waterbodies, Streams - NHD Counties - CO Dept. of Local Affairs, All Others - DRCOG
This data is intended for informational purposes only. DRCOG provides this information on an "as is" basis and makes no representation or warranty that the data will be error free. DRCOG is not responsible to any user for costs or damages arising from inconsistencies in its data.
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Cherry Creek Watershed
Watershed description The Cherry Creek Watershed covers approximately 400 square miles. The headwaters are located in El Paso County and flow northward through eastern Douglas County before emptying into Cherry Creek Reservoir in Arapahoe County. The Reservoir is a major feature and is the watershed’s designated downstream limit. Below the reservoir, Cherry Creek joins the South Platte River in the South Platte Urban Watershed. The southern portion of the watershed is rural while much of the northern part is urban. Cherry Creek State Park is an important area for urban recreation and wildlife habitat, providing 4,000 acres of land adjacent to the reservoir. Water quality management The Cherry Creek Basin Water Quality Authority is the designated management agency for the watershed. The Authority’s mission is to “maintain the beneficial uses in the Cherry Creek Reservoir by preserving its water quality.” It is responsible for managing wastewater treatment and assuring implementation of the water quality management plan. The Cherry Creek Reservoir Watershed Plan, approved by DRCOG in 2003, identifies management strategies to make progress toward water quality goals. The Cottonwood Wastewater and Sanitation District (CWSD) plant was decommissioned and its service area is now covered by the Arapahoe County Water and Wastewater Authority (ACWWA). The six remaining facilities have submitted wastewater utility plans that have been approved. Figure 9 shows location of the permitted wastewater treatment facilities in the Cherry Creek Watershed, and Table 9 provides details of the permitted facilities in the watershed.
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Table 8 : Cherry Creek Watershed Wastewater Treatment Facilities
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Cottonwood was decommissioned, is served by ACWWA and is included in ACWWA’s 2004 WUP Inverness is expected to be decommissioned in 2010 and served by ACWWA 3 PWSD facilities will have a hydraulic capacity of 4.0MGD, but have a permit of 3.6 MGD due to phosphorous limitations
2
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East Plains Watershed
Watershed description The East Plains Watershed begins near the eastern edge of Denver International Airport (DIA) and extends eastward to the limits of the Denver Regional Council of Governments’ (DRCOG) planning area. The DRCOG portion of the East Plains Watershed is located in parts of Adams and Arapahoe counties. The watershed totals 3,710 square miles beginning at the southern end in Elbert County and extending into Weld and Morgan counties at the northern extent, outside of the DRCOG planning area. Within the DRCOG planning area the watershed includes the towns of Bennett and Deer Trail, the rural communities of Byers, Strasburg and Watkins, and portions of the City of Aurora. Wastewater treatment facilities are operated by municipalities or special districts to serve these communities. For example, the Byers Water and Sanitation District and Eastern Adams County Metropolitan District provide wastewater service to Byers and Strasburg, respectively. The watershed is defined by a number of plains streams that flow from south to north and ultimately confluence with the South Platte River. There are four primary hydrologic drainages or subwatersheds: Box Elder, Kiowa, Bijou Creek and Beaver Creek. The Box Elder Creek drainage begins in the East Plains Watershed and flows into the Beebe Draw Watershed at the boundary of DIA. The Kiowa and Bijou drainages are further east and include the majority of point source dischargers. The Beaver Creek Watershed includes the most easterly portions of Adams and Arapahoe counties. The vast majority of land in the East Plains Watershed consists of dryland wheat farming. The western edge of the watershed is experiencing the expansion of the Denver urbanized area. The towns of Bennett and Deer Trail and the unincorporated communities of Watkins, Byers and Strasburg all lie on the I-70 corridor. Water quality management The designated management agencies in the East Plains Watershed include the City of Aurora (with the Metropolitan Wastewater Reclamation District), the Town of Bennett, the Town of Deer Trail, and Adams and Arapahoe counties. The towns and the two counties are responsible for non-point and stormwater source management activities. In the non-DRCOG portions of the watershed, various agencies provide water quality planning and management. The Water Quality Control Division is responsible for water quality management in Elbert and Morgan counties. The North Front Range Water Quality Association is the planning agency in Weld County and has an approved water quality plan that includes its portion of the East Plains Watershed. The Water Quality Control Commission has designated a portion of Beaver Creek as impaired for selenium and E. coli.
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Nine wastewater treatment facilities are located in the Eastern Plains Watershed (Figure 10). Table 10 provides details of the facilities in the watershed.
Table 9 : East Plains Watershed Wastewater Treatment Facilities
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South Platte Urban Watershed
Watershed description The South Platte Urban Watershed encompasses 828 square miles. The major feature is the mainstem of the South Platte River from the outlet of Chatfield Reservoir to the confluence with Big Dry Creek. The watershed includes the lower portions of Bear Creek (below Bear Creek Reservoir), Cherry Creek (below Cherry Creek Reservoir), and Clear Creek (below Golden); other watersheds include the upper portions of these creeks. Other major tributaries include Sand Creek; First, Second, and Third Creeks; and the southern Big and Little Dry Creeks. Human activity has significantly modified all of these hydrological features. The reservoirs mentioned above and many canals originally constructed for agricultural irrigation regulate flows in the streams. Stream channels are often artificially confined and riparian areas are developed for urban uses. The South Platte Urban watershed is the most urban of the DRCOG region’s watersheds. It includes most of the City and County of Denver as well as large portions of Adams, Arapahoe and Jefferson counties. The Highlands Ranch and Lone Tree areas of Douglas County also lie within this watershed. It contains the Denver Central Business District, the most densely developed area in the entire region, as well as major employment centers such as the Denver Tech Center, the Fitzsimmons Medical Complex and Denver International Airport. The watershed contains all or portions of the following cities and towns: Arvada, Aurora, Bow Mar, Brighton, Centennial, Cherry Hills Village, Columbine Valley, Commerce City, Edgewater, Englewood, Federal Heights, Foxfield, Glendale, Golden, Greenwood Village, Lakewood, Littleton, Lone Tree, Morrison, Northglenn, Sheridan, Thornton, Westminster and Wheat Ridge.
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Water quality management A voluntary association called the South Platte Coalition for Urban River Evaluation (SP CURE) coordinates among the multiple water quality management agencies in the South Platte Urban Watershed. Although not formally recognized as a management agency in the Clean Water Plan, the association provides valuable coordination of a number of water quality activities in the watershed. The list below identifies the designated agencies for point sources and nonpoint sources. Point sources • Adams County Water Quality Association • City of Aurora • Centennial Water and Sanitation District • Golden/Coors • Littleton/Englewood • Metro Wastewater Reclamation District • South Adams County Water and Sanitation District
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Nonpoint sources • All general-purpose governments (cities, towns and counties) within the watershed Water quality issues in the watershed are focused on the water bodies that are on the current 303(d) list of impaired stream segments. While Barr Lake and Milton Reservoir are not in the South Platte Urban Watershed, their listing on the 303(d) list for exceeding pH levels affect the watershed. The Barr Milton Watershed Association (BMWA) is working to develop a TMDL. Table 11 shows permitted wastewater treatment facilities in the South Platte Urban watershed. Nine of the 13 facilities have submitted a wastewater utility plan (WUP) for review. Figure 11 depicts shows the wastewater treatment facilities in the watershed, including plants that serve the South Platte Urban basin, but discharge to other watersheds (Northglenn and Plum Creek). Table 10 : South Platte Urban Watershed Wastewater Treatment Facilities
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The Metro NTP is in the initial stages of planning The Sky Ranch district will replace the Foxridge facility, which holds permit CO-0028908
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Upper Clear Creek Watershed
Watershed description The Upper Clear Creek Watershed covers an area of about 400 square miles in Gilpin, Clear Creek and Jefferson counties. The headwaters occur along the east side of the Continental Divide, where elevations reach more than 14,000 feet above sea level. From there, numerous streams drain to Clear Creek and flow generally east for about 40 miles to Golden. Clear Creek becomes part of the South Platte Urban Watershed at an elevation of 5,700 feet. Large surface flows in narrow canyons on Clear Creek can lead to flooding and sediment loading. The geologic characteristics of the watershed led to numerous and dispersed mining activities over the last 150 years. Mining operations resulted in large amounts of metals released into nearby streams. Recently, phosphorus loading has become an increasing concern, especially when released to downstream communities where nutrients are already a major issue. The Clear Creek Watershed is an important source of water for the Denver region. Most of the water comes from snowfall at higher elevations along the Continental Divide. Spring runoff provides water to several large cities along the Front Range including Thornton, Westminster and Northglenn. As a result, downstream cities are keenly interested in maintaining high water quality standards in the Upper Clear Creek Watershed. Most land use in the watershed is public, existing mainly in the National Forest System. The next largest land use is private land related to patented mining claims. Most of these claims are inactive at this time, having been converted to residential use or idled. Water quality management The Upper Clear Creek Watershed Association is the management agency for the watershed. It works to: • maintain an effective water quality management system through stream monitoring, data collection and modeling; and • ensure cost-effective local wastewater management systems within the parameters of the Clean Water Plan. Of 17 different stream segments defined by the WQCC, eight are on the 2004 303(d) list of water-quality limited segments requiring TMDL studies. For the majority of these segments, pollutants of concern are metals: copper, cadmium, iron, manganese, lead, and zinc. Detailed information regarding metals loading can be found in the Upper Clear Creek Watershed Trace-Metals Data Assessment by TDS Consulting of Evergreen. On one impaired segment of North Clear Creek, aquatic life is also listed as impaired.
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The watershed is part of the Standley Lake Agreement. Through this agreement, a total of 25 counties, municipalities, special districts, canal companies and industries established a narrative standard for total species of phosphorus and nitrogen on Clear Creek and Standley Lake (Clear Creek/Standley Lake Watershed Agreement). As a result of this standard, entities in the watershed are working to improve the removal of nitrogen and phosphorus from
the wastewater plant effluent and onsite treatment systems flowing into the waterways. The agreement also established an extensive monitoring program across the watershed. At present there are eight major municipal wastewater treatment plants located in the Upper Clear Creek Watershed. Figure 12 shows the location of Wastewater Utility Service Areas (WUSAs) and facilities in the watershed.
Table 11 : Upper Clear Creek Watershed Wastewater Treatment Facilities
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The Coors facility contains an 8.0 MGD process wastewater facility and a 5.0 MGD general wastewater facility.
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Upper South Platte Watershed
Watershed description The Upper South Platte Watershed extends from the Strontia Springs Reservoir to the headwaters of the South Platte River in Park County. The watershed covers approximately 2,600 square miles of central Colorado and more than 1.2 million acres of public lands. It provides municipal water for about 75 percent of Colorado’s residents and is home to numerous threatened and endangered species. The watershed is defined by several streams that flow into the north and south forks of the South Platte River. Most of the watershed is outside the DRCOG region, but its water quality directly affects Chatfield Reservoir in the DRCOG region. The vast majority of land in the Upper South Platte Watershed consists of national forests. A number of small communities, such as Fairplay and Woodland Park, are located in the Park County portion of the watershed. In the DRCOG portion of the watershed, the only non-federal developments are located along US Highway 285. The only area of sufficient density to require centralized water and sewer service is the subdivision served by the Mountain Water and Sanitation District. Water quality management In the DRCOG portion of the Upper South Platte River Watershed, the only management agencies are Jefferson County and Douglas County. The four operating agencies are Mountain Water and Sanitation District, Camp Shady Brook, the Elk Creek Elementary School and the Lost Valley Ranch. An additional eight treatment facilities are located in Park and Teller counties in the upper portion of the watershed, and are included in the Pikes Peak Area Council of Governments water quality plan. Four water bodies in the Upper South Platte Watershed are on the current 303(d) list of impaired stream segments. The Twin Creek portion of Segment 2a and Trout Creek plus its tributaries located on Forest Service land (part of Segment 3) are listed for sediment. One segment, The Hall Valley portion of Segment 4, is listed as impaired for copper; Geneva Creek is listed as impaired for copper and zinc. The two segments have temporary modifications of these standards until February 26, 2010. Twelve wastewater treatment facilities are located in the Upper South Platte Watershed (Table 13). Four of the facilities (Mountain Water and Sanitation District, Camp Shady Brook, Elk Creek Elementary School and the Lost Valley Ranch) are within the DRCOG planning area. Information about the other facilities is available from the WQCD or the Pikes Peak Area Council of Governments. Figure 13 illustrates the locations of the permanent wastewater treatment facilities in this watershed.
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Table 12 : Upper South Platte Watershed Wastewater Treatment Facilities
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