MIAMI GRAY WATER PRIMER
                                                   BISCAYNE LANDING TOWNCENTER
                                                        COMMERCIAL INDOOR REUSE


This document was prepared by                                                                                   EXECUTIVE SUMMARY
                                                                                                                Boca Developers and the Biscayne Landing Town Center design team, led by
                                                                                                                Arquitectonica, want the Biscayne Landing Office Tower to be a flagship green
                                                                                                                pilot project. To do this, we are proposing sustainable design features and tech-
RANA CREEK                                                                                                      nologies that are new and innovative to Florida but well tested in other parts
LIVING ARCHITECTURE                                                                                             of the United States and abroad.
contact:: J. Brent Bucknum
35351 E. Carmel Valley Road                                                                                     This document serves as a primer for one of these technologies, a large-scale        Unique Florida Mangrove Ecosystem
Carmel Valley, CA 93924
T: 831.659.3820
                                                                                                                commercial gray water recycling system, which will capture water from office
F: 831.659.4851                                                                                                 lavatory sinks, treat the water to Florida water reuse standards and recirculate                                                                                               it to lavatories for flushing toilets. The system will save as much as 1.6 million
                                                                                                                gallons of potable water per year. It will also set an example as a development
                                                                                                                that reduces strain on the overdrawn Biscayne Aquifer.
in colaboration with

TLC ENGINEERING fOR                                                                                             When many people think of gray water recycling, they think of small residential
ARCHITECTURE                                                                                                    systems for landscape irrigation that are simple, low-tech, and “do-it-yourself ”.
Guillermo R. Gonzalez, CIPE                                                                                     However, large-scale gray water recycling systems for building reuse are, in fact,
Plumbing Engineer
5757 Blue Lagoon Drive, Suite 400
                                                                                                                highly automated, sophisticated waste treatment technologies. These systems
Miami, FL 33126-2078                                                                                            have been proven in residential and commercial applications in multiple coun-
(305) 266-6553 office phone                                                                                     tries (notably Germany) over the past 15 years. Included in this Gray Water
(305) 266-6695 office fax                                                                                       Primer are reviews of four well-known manufacturers and case studies of their
Anne Cotter, AIA, LEED AP
Vice President                                                                                                  As we are proposing the first system of its kind in Florida, the design team is
801 Brickell Avenue Suite 1100                                                                                  committed to diligently working with the permitting agencies to ensure that
Miami . Florida 33131 USA                                                                                       all parties are in support of the system, and that it meets or exceeds all code
T 305.372.1812
F 305.372.1175
                                                                                                                requirements. A review of the applicable Florida codes and relevant permitting                                                                                      agencies is included. We have also provided a “road map” to successful permit-                                                                                          ting of the system and hope to work with each agency to refine this process.
                                    BISCAYNE LANDING TOWN CENTER design by Arquitectonica International Corp.

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                                                 INTRODUCTION TO GRAY WATER                                                                                                                 treatment systems can essentially eliminate risks. Many jurisdictions are beginning to encourage gray water systems for their
                                                                                                                                                                                            significant environmental benefits, or simply due to practical issues with wastewater treatment capacity. The New South Wales
                                                 WHAT IS GRAY WATER?                                                                                                                        Government Department of Water and Energy’s newly released greywater diversion rules and the recent passage of greywater
                                                                                                                                                                                            legislation in the state of Montana reflect growing benefit recognition (see “Code Considerations” for a detailed discussion of
                                                   Gray water (synonymous with greywater) is non-industrial wastewater generated from domestic processes such as hand                       regulations).
                                                   washing, laundry and bathing. Gray water comprises approximately 40% of commercial wastewater, and can be treated onsite
                                                   and then employed for non-potable uses (a process referred to as “gray water recycling or gray water reuse”). Gray water is            WHY SHOULD MIAMI PROMOTE GRAY WATER RECYCLING?
                                                   distinct from black water (wastewater containing toilet effluent) in the amount and composition of its chemical and biological           The State of Florida already encourages the use of reclaimed water and permits gray water recycling. The WASD explains, “As
                                                   contaminants, tending to be cleaner (see “What is the quality of gray water?” below). Process water is also distinct from gray           Miami-Dade County’s population continues to increase, so does our demand for drinking water. Like all natural resources, the
                                                   water. It refers to wastewater from cooling towers and other HVAC or industrial processes. Both black water and process                  Biscayne Aquifer, Miami-Dade County’s current source of drinking water, is not limitless. The use of reclaimed water and gray
                                                   water can also be recycled, but the processes are not the same. Gray water gets its name from its cloudy appearance and                  water in Miami-Dade County helps preserve the Biscayne Aquifer.” Aquifer preservation safeguards public health and business
                                                   from its status as being neither fresh (clear water such as potable groundwater), nor heavily polluted (black water).                    viability. Onsite reuse of gray water confers additional benefits, including savings in energy and infrastructure. Since commercial
                                                                                                                                                                                            buildings can comprise 20% of urban water demand, savings from gray water recycling in this sector (sometimes an 80-90%
                                                   Reclaimed water is different from all of the above reusable water sources. Reclaimed water refers to municipal wastewater                reduction in potable use) can significantly reduce aquifer draws and wastewater load.
                                                   that has undergone advanced treatment and arrives at buildings via “purple pipe”.
Typical Commercial Building Water Use                                                                                                                                                     WHAT IS THE QUALITY OF GRAY WATER?
                                                   Both onsite gray water recycling systems and local water reclamation facilities have benefits compared with centralized sewage
                                                   treatment plants, and these benefits generally increase with degree of decentralization. They include resource efficiency, aquifer      As the table below shows, gray water tends to have much lower levels of pollutants than blackwater from toilets or kitchen gar
                                                   water conservation and reduced sewage loads. Onsite gray water treatment is also energy efficient, as it does not require               bage disposals. In some applications, (such as subsoil irrigation in areas with low water tables), gray water can potentially be
                                                   electrical energy to pump water to and from a centralized treatment plant.                                                              used without treatment. However, most gray water requires treatment before it is safe for reuse, especially in applications with
                                                                                                                                                                                           some level of human contact. The exact composition of gray water depends on the source (sink, shower, etc.), the use patterns,
                                                 HOW LONG HAS GRAY WATER BEEN IN USE?                                                                                                      as well as the composition of the original water stream. For example, if tap water has high salt concentrations, gray water will
                                                   Reuse of gray water has been occurring informally for centuries, but its formal implementation and regulation began more                too. The following table discusses some components typically found in gray water.                                                      Bottom: In early 2002, a patch of waste
                                                   recently. Water crises in the early nineties increased awareness of the need to find innovative ways to conserve. and wisely                                                                                                                                                   water spanning over 60 miles in diameter
                                                   use limited water resources. Early systems tended to be residential scale “do it yourself ” systems with minimal treatment and           Component          Description                         Common Source                         Purication                              formed off southwestern Florida and
                                                   reuse for irrigation. More sophisticated systems for irrigation were developed by companies like Earthstar and Clivus Multrum.                                                                                                        strategy                                 contributed to severe coral reef stress
                                                                                                                                                                                            Pathogenic     Bacteria, viruses, protozoa             Fecal matter present in small amounts Disinfection                             and death in the Florida Keys. The im-
                                                   Germany has one of the longest histories of larger commercialized gray water recycling systems, with pilot projects beginning            Microorganisms                                         in shower, bath, wash or sink water                                            ages above show elevated phytoplankton
                                                   in the nineties. Today, systems recycling gray water into non-potable water suitable for building applications such as toilet flush-
                                                                                                                                                                                                                                                                                                                                  activity resulting from the patch. Sustain-
                                                   ing are quite common in Germany, and exist in many other countries as well, including the UK., Spain, China, Australia, Canada           Biochemical  The amount of oxygen it would take Food residues from sinks, oil-based          Physical and biological
                                                                                                                                                                                                                                                                                                                                  able managment of waste water can help
                                                                                                                                                                                            Oxygen       to decompose present organic matter bath products                               ltration
                                                   and the US. Commercial manufacturers include Brac, Lokus, Pontos and GE Zenon.                                                           Demand (BOD) (higher BOD = more organic matter)                                                                                       prevent sewer overflow and consequent
                                                                                                                                                                                                                                                                                                                                  ecological damage.
                                                 HOW DO GOVERNMENTS REGULATE THE USE OF GRAY WATER ?                                                                                        Suspended          Any solids, organic or inorganic    All gray water sources                Physical ltration
                                                                                                                                                                                            Solids (TSS)
                                                   ‘Gray water’ is still legally defined in most US jurisdictions to be ‘Sewage’, and is not distinguished from black water. Under          Nutrients          Nitrogen and phosphorus primarily   Soaps and detergents, food residues   Physical and biological
                                                   that definition gray water is commonly bound by the same regulatory procedures enacted to ensure properly engineered                                                                                                                  ltration
                                                   septic tank and effluent disposal systems are installed for long system life and to control spread of disease and pollution. In          Other              Includes salts, chlorine, etc.      Soaps and detergents, products such   Filtration, education to
                                                   such regulatory jurisdictions this has commonly meant domestic greywater diversion for garden irrigation was either simply               chemicals                                              as paints and solvents improperly     avoid contamination
Clivus Multrum System recycling gray water for                                                                                                                                                                                                     poured down the drain
                                                   not permitted or was discouraged by expensive and complex governmental sewage system approval requirements. It is now
subsurface irrigation (not recommended for
                                                   recognized and accepted by an increasing number of regulators that the microbiological risks of greywater reuse at the single
Miami due to sensitive, high water table)                                                                                                                                                  See Appendix for a detailed list of component sources and appropriate treatments.
4                                                  dwelling level where inhabitants already had contact with that gray water are low, and at the multifamily or commercial scale,                                                                                                                                                                                           5

                                      Storage and use of untreated gray water: As shown, greywater can contain bacteria and organic matter, which will quickly
                                      develop disease-inducing pathogens if stored untreated in a warm climate. Ideally gray water should be used immediately for
                                      non-potable applications, or treated for short-term storage. Untreated gray water cannot be used as flush-water as it will start
                                      to smell and discolor the flush toilet fixture if left for a day or more. There would also be a possibility of exposure to patho-
                                      gens through splashing or air contact. However, as discussed in this document, only minimal treatment is required to reach an
                                      acceptable standard for flushing reuse.

                                       The South Florida climate has particular challenges such as year-round humidity and pest control. Metropolitan South Florida
                                       emerged from the swampland of the Everglades, and consequently has a high water table. An advantage to the climate in
                                       South Florida is the rain. Besides a very active hurricane season (June 1 through December 1), there is also an extensive rainy
                                       season. This presents a great opportunity for green design and water efficient innovation. The problem is that many communi-
                                       ties focus only on handling water runoff and drainage (water as waste) instead of focusing their energies on water collection
                                       and reuse (water as resource).

                                       Landscape Application: With abundant rainfall and a water table only a few feet below the surface, Florida’s paramount water
                                       concern is safely disposing of contaminated water. It makes little sense to reuse graywater for irrigation on the Biscayne site
                                       when we would have to drain out 2/3 of the water collected because of abundant rainfall. In fact, the water table is so high
                                       in the region that our drainfield is required to be mounded about 18” above the surface in order to avoid contaminating the
                                       groundwater. Additionally, the project area has fissured limestone aquifers. The bedrock is a network of open, water filled
                                       caves that channel water rapidly without treatment directly to the aquifer. This means that quality of water to be land applied
                                       must approach drinking water standards. The brownfield status of the site and proximity of Mangrove preserve further indi-
                                       cate that land application of non-potable water could be risky.

                                       Mechanical Reuse: HVAC and industrial systems require copious amounts of water. Treated gray water can be used to offset
                                       potable use in these applications, since potable quality is generally not necessary. However, treatment systems must maintain
                                       potentially corrosive water components at a particularly low level for mechanical reuse. Although it is worth evaluating the
                                       potential for mechanical gray water reuse, reclaimed water may be a preferable option for cooling towers and other applica-
                                       tions (see Rana Creek’s Cooling Tower Reuse Document for further information).

                                       Building Reuse for Toilet flushing: For efficiency, ease of implementation, and environmental protection, we propose that gray     Diagram showing gray water collection, treatment and reuse options (source: Zenon)
Oleta River State Park - Florida’s
                                       water be treated and reused for flushing at the Biscayne Landing Office Building. In this type of system, water from lavatory
largest urban park.
                                       sinks and showers (if present) will be separately piped to a treatment system. Once purified, the water will be pumped to the
                                       building’s toilets (and urinals, if waterless urinals are not used). A number of packaged and custom in-building greywater treat
                                       ment systems are available to Biscayne. Four of these systems are presented below for informational purposes (not to pro
                                       mote any particular system), and there may be other options available.

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                              BRAC SYSTEMS                                                                                              PONTOS
                                Brac is a Canada-based company that manufactures the Residential Grey Water Recycling (RGW) Systems. They are indoor-                  Pontos is a German-based company that manufactures the Aqua Cycle line of gray water treatment systems. The Aqua Cycle
                                installed systems available in four sizes: RGW-150 (39 gallons), RGW-250 (66 gallons), RGW-350 (92.5 gallons) and RGW-450              is an indoor system with sizes appropriate for both homes and larger buildings. The largest system offered can process 13,500
                                (119 gallons). These systems are all much smaller than needed for the Biscayne Office Building, but are worth knowing about            liters (3,566 gallons) of gray water per day.
                                as they may be applicable for other local projects.
                                                                                                                                                                                                                                      The Aqua Cycle treats water without the use of chemicals.
                                The RGW system removes particles using a 100 micron filter, and disinfects gray water using a managed chlorination system                                                                              The four-stage process includes two stages of biological
                                (MCS). The MCS circulates and chlorinates the water at pre-programmed intervals. The entire treatment process, from gray                                                                               treatment and ultrviolet (UV) disinfection. An advantage of
                                water intake to treatment to storage of treated water, takes place in a single tank.                                                                                                                   this treatment regime is that the water it produces does not
                                                                                                                                                                                                                                       contain chemical residues, such as chlorine,. It can conse-
                                Performance testing certified by the Society of Environmental Expertise (Sodexen) in Quebec on June 3, 2006 shows that the                                                                             quently be used for more quality-sensitive applications, such
                                Brac system achieves acceptable disinfection (see chart). IAPMO Research and Testing certifies that the Brac system meets                                                                              as irrigation.
                                the International Plumbing Code (IPC). Building officials in in four Florida counties have verified that the BRAC system is per-
                                missable under Florida codes, and one system has been installed (see below case study and code section for more detail).                                                                               Water treated by the Aqua Cycle systems meets the strict
                                                                                                                                                                                                                                       European Union (E.U.) Directive for Clean Recreational
                                Operational considerations include a need to periodically clean filters (depending on influent water quality), and the possibility                                                                     Water Quality This means that it is safe not only for toilet
                                that toilet water may appear slightly cloudy. Annual maintenance supply costs are estimated at less than $100.                                                                                         flushing, but also for clothes washing and, as mentioned above,
                                                                                                                                                                                                                                       landscape irrigation. The Aqua Cycle 13500 consumes 16.9
                                The RGW system was named a Top Ten Green Building Product for 2007 by Sustainable Industries Journal (USA), and Brac                                                                                   kWh of electricity per day (equivalent to a constant 700W
                                Systems was awarded Best New Product in the Energy Efficient category at Mecanex Climatex 2007 (Canada).                                                                                               load). This is similar to the power draw of a household refrig-
                                                                                                                                                                     CASE STUDY: TRAINING CENTER AND APARTMENTS
                                Florida’s Green Envirohome in Indialantic, FL (shown at left) is being outfitted with
                                a Brac system. In addition to gray water recycling, the home will showcase environ-                                                    At the 85-room Training Center in Schonblick, Germany, an Aqua Cycle 3300 gray water system treats up to 870 gallons of
                                mentally-friendly technologies such as solar air conditioning and hot water heat-                                                      water per day from showers and reuses it for toilet flushing. In Ansbach, Germany, the Aqua Cycle 2400 treats water from
                                ing, Structural Insulated Panel (SIP) construction and water and energy monitoring                                                     showers and bathtubs in 16 apartments and reuses it for toilet flushing. Water demand that is unmet by gray water supply is
                                systems.                                                                                                                               filled through an integrated rainwater collection system.

                                A Brac system, installed at a four-person residence in Ruidoso, NM, was tested in the                                                CASE STUDY: STUDENT RESIDENCE HALL
                                summer of 2006. Results showed that annual greywater harvesting from the tub,
                                shower, sink and washing machine was 10,480 gallons. Of this water, 2700 gallons                                                       The images at center and bottom right show a Pontos Aqua Cycle 12,500 designed for a student residence hall renovation in
                                per year are reused for toilet flushing, and the remaining 7780 gallons are used to                                                    Mainz, Germany. This larger system is placed in a mechanical room rather than in the occupied space. It treats shower and
                                irrigate fruit trees and landscaping. Similar results were achieved in a home in British                                               sink water from 300 rooms, and sends treated water back for toilet flushing.
                                Columbia, Canada.
                                                                                                                                                                       Over twenty additional case studies of installed systems can be viewed on the Pontos website, from hotels to multi-family
                                                                                                                                                                       residences, schools to fire departments. These projects are located in multiple countries, primarily in Europe.
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                                                    LOKUS                                                                                                                   GE - ZENON
                                                       Lokus is a German-based company that manufactures custom gray water treatment systems, including high-volume systems for                  ZENON is a GE-owned company based in Canada that manufactures large commercial and industrial-scale treatment systems
                                                       commercial buildings. The systems treat gray water using a biological wastewater treatment system, the centerpiece of which               for gray water as well as blackwater (sewage). The compact Z-MOD packaged system is made to be installed underground.
                                                       is a Rotating Biological Contactor (RBC). Characteristic wastewater bacteria populate the large surface area of the polyeth-              Its cenral component is the ZeeWeed membrane bioreactor (MBR). The complete treatment process consists of fine screen-
                                                       ylene rotating contactors and consume the biologically degradable waste particles. The optimal oxygen supply is provided by               ing (2 mm internally fed traveling band screen), grit removal, fine bubble aeration, membrane (MBR) filtration and UV disinfec-
                                                       the revolving rotors. The surplus biological sludge is then allowed to settle in a secondary settling tank. The biologically treated      tion. ZeeWeed MBR systems can be custom designed to produce water of essentially any quality. They have been used both
                                                       graywater is then disinfected by means of UV-radiation and stored in a service water tank. From there the water is pumped                 as whole-house drinking water filters, and in community wastewater treatment facilities. Data below show some possible
                                                       into the separate mains network for service water and distributed to end use points. The storage tank is automatically re-                outflow water quality where influent included blackwater. While most Zenon systems are more robust and expensive than
                                                       plenished with potable water when the treated gray water is in short supply. Treated gray water from the system approaches                necessary for building gray water recycling, the company is capable of customizing systems to fit Biscayne’s needs.
                                                       drinking water quality, and meets bathing standards according to the European Union Directive. More detailed water quality
                                                       data can be found in the table below at left. Although the system is generally low-maintenance, past use has suggested a few           CASE STUDY: KEY COLONY BEACH WWTP
                                                       important factors. Since the system creates a high-humidity environment, equipment sharing space with it should be corro-                In Key Colony, FL, a water reuse plant designed by US Greiner treats brackish wastewater (gray water and black water) to
                                                       sion-resistant. Control visits should occur at least monthly, and maintenance visits twice annually.                                     Florida’s 5,5,3,1 standard using the ZeeWeed MBR and, for 10% of the effluent, reverse osmosis. The plant processes 250,000
                                                                                                                                                                                                to 750,000 gallons per day, and treated water is used to irrigate a golf course. Below is a quality data set for this facility.

                                                                                                                                                                                              Source: Data above are from Thompson, Schneider and Murphy, 2003

                                                                                                                                                                                              CASE STUDY:VIEJAS INDIAN RESERVATION
                                                                                                                                                                                                In San Diego County, the Viejas Reservation operates an expanding casino and shopping center. To accomodate this growth,
                                                                                                                                                                                                the Tribal Council selected a ZeeWeed system for its adaptability and high quality. The Viejas plant effluent meets California
                                                                                                                                                                                                tertiary standards for reclaimed water, and is used primarily in the HVAC system as process water.

                                                                                                                                                                                              CASE STUDY: CONVENTION CENTERS
                                                                                                                                                                                                In Downtown Pittsburgh, PA, the 1,486,000 sqft David L. Lawrence Convention Center (below left) was completed in 2003.
                                                    CASE STUDY: THE fOUR-STAR HOTEL ARABELLA                                                                                                    The world’s first green certified convention center (LEED Gold), it makes use of a Zenon gray water system to recycle sink
                                                      The Bavarian Industrie und Gewerbe Bau GmbH & CO, Munich, hired Lokus to manufacture a six-stage gray water plant for                     and driking fountain water for toilet and urinal flushing. The system recycles 50 percent of the Center’s water and saves an
                                                      the four-star hotel ‘Arabella’. The system, one of the first of its kind worldwide, treats gray water produced in the hotel’s 400         estimated 6.4 million gallons annually, reducing potable water consumption by over 60 percent. The planned Vancouver Con
                                                      guestrooms. This plant has a cleaning capacity of 20,000 liters (5283 gallons) per day, and has been operating successfully since         vention Center (center right) will treat both black water and gray water with a Zenon system. Rana Creek is working with
                                                      January, 1996.                                                                                                                            the design team to set new standards for green roof and living systems integration, reusing wastewater on the roof.

                                                    CASE STUDY: OEKO-TECHNIK PARK                                                                                                                                                                                                                                                  From top: ZeeWeed MBR, system diagram
From top: Hotel Arabella exterior; Hotel Arabella                                                                                                                                                                                                                                                                                  (conventional vs. ZeeWeed), Vancouver Con-
system (control panel, RBC group and settling
                                                      The Oeko-Technik Park in Hannover, Germany is a community of residences with a school and church that has been retrofit-
                                                                                                                                                                                                                                                                                                                                   vention Center, Viejas Reservation System
tank); RBC unit for Oeko-Technik Park Apts.;          ted with ecological water treatement and recycling systems. Lokus installed an RBC system to treat gray water from a 24-unit
Water quality data from a Danish Apartment            apartment building. The system, pictured at left (second from bottom), cost € 26,000.
Building, Copenhagen. DK.
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                                                  SyStem DeSign PARAmeteRS                                                                                                                                    In the 3000-6500 gpd size range, Pontos AquaCycle and Lokus have manufactured systems. Brac systems tend to be too small
                                                                                                                                                                                                              and Zenon systems tend to be overbuilt for the commercial gray water application. However, we have spoken with both compa-
                                                  As the case studies above suggest, there are a number of options to choose from when selecting a gray water treatment system.                               nies, and they are capable of designing custom systems to suit Biscayne Landing’s needs.

                                                  System Sizing: One of the first choices to be made is system size. The system needs to be large enough to collect, convey, treat,                           Note that to achieve the lowest overall building water use, the most efficient fixtures (low-flow faucets, waterless urinals) should
                                                  store and supply the entire gray water volume intended for recycling. It will need to have a method of dealing with excess gray                             be selected. Although this results in a smaller amount of reused gray water (and a higher potable demand for flushing) than the
                                                  water as well as a method of supplying back-up water when gray water volumes are insufficient. Gray water systems are generally                             maximum flow scenario above, the difference is more than accounted for in the reduced faucet demand. It would be an inefficient
                                                  sized by daily volumetric treatment capacity (gallons per day or GPD). There are various methods of determining expected gray                               choice to use more potable water than necessary in faucets just to increase available gray water for flushing. As the chart above
                                                  water volume, resulting in varied estimates for Biscayne’s GPD. Average use numbers based on occupancy and square footage                                   shows, the minimum water use (efficient fixture) scenario has a lower overall potable water use even though it makes use of a
                                                  suggest that the Biscayne Landing Office Building will produce anywhere between 1700 and 10,000 gallons of gray water per day.                              larger volume of gray water.
                                                  The calculation method used in LEED WE3.1, which is based on flow rates of plumbing fixtures and standard use patterns, puts
                                                  the range at 3000 – 6500 gpd (3000 gpd if low-flow, efficient faucets are used, and 6500 gpd if faucets meeting national maximum                           filtration and Disinfection Technologies: Once sizing needs are determined, one must consider treatment technology choices.
                                                  allowable flow are used). These calculations are summarized in the table below.                                                                            Various methods for filtration and disinfection exist. The most widely-used options for filtration are physical (screening media
                                                                                                                                                                                                             that capture and remove particulates), activated carbon (a polishing filter that removes pollutants both through physical means
Greywater Calculations for Biscayne Landing Office Building (LEED WE3.1 Method)
                                                                                                                                                                                                             and chemical reaction), reverse osmosis (a membrane conveys contaminants out of water) and biological (microorganisms that
Fixture Type                 Flowrate       Flowrate       Water gal/use          Water gal/use    Daily Uses       #             Total Daily Use (gallons -         Total Daily Use (gallons -       BRAC Estimateand break down pollutants). Available options for disinfection include chemical treatment (chlorine or iodine), ultraviolet
                             (max case)     (min case)     (max case)             (min case)                        Occupants     max case)                          min case)                        (1     light (UV) treatment and Ionization (using ozone or copper/silver). In chemical treatment, the chlorine or iodine is regularly added
Lavatory Faucet (15 sec/use) 2.5 gpm        .5 gpm                          0.6              0.1              3           1737                           3256.9                             651.4
                                                                                                                                                                                                             directly to the water and kills all microbes. In UV treatment, water flows under UV light, which neutralizes microbes. In ozone
Shower (5 minutes/use)         2.5 gpm      1.8 gpm                        12.5                9            0.1           1737                           2171.3                            1563.3
Kitchen sink, non-residential (2.5 gpm      1.8 gpm                         0.6              0.5              1           1737                           1085.6                             781.7            ionization, UV light causes oxygen (O2) to rebind as ozone (O3), a highly reactive compound which destroys microbes in water.
                                                                                                                                                                                                             In copper/silver ionization, water flows across ionized metal rods, killing microbes. The relative benefits of these systems are sum-
Total greywater produced (gallons/day)                                                                                                                   6513.8                            2996.3                1737
                                                                                                                                                                                                             marized in the following table.
Water Closet (Toilet)
male                         n/a            n/a                             1.6              1.1                1           869                          1390.4                             955.9
female                       n/a            n/a                             1.6              1.1                3           869                          4171.2                            2867.7
Urinal                       n/a            n/a
male                         n/a            n/a                              1               0.5                2           869                            1738                               869

Total recycled water demand for flushing (gallons/day)                                                                                                   7299.6                             4692.6
                                                                                                                                                                      with waterless urinals: 3824
Potable demand for flushing (demand in excess of greywater supply)                                                                                        -785.9                           -1696.3
                                                                                                                                                                      with waterless urinals: -827
% flushing demand met by greywater                                                                                                                             90%                             60%                37%
                                                                                                                                                                       with waterless urinals: 80%
Water saved annually by displacing flushing water with treated greywater                                                                              1693588.0                           779038.0             451620
Total potable water use by plumbing fixtures                                                                                                             7299.7                             4692.6
                                                                                                                                                                     with waterless urinals: 3823.3
Building Occupants = 2,380 Full Time Equivalent (FTE)
                                                                                                                                                                                                                                                                                                                                                     Top: Large-scale UV treatment in a waste treat-
Occupants are assumed to be 50% male, 50% female (1190 each)                                                                                                                                                                                                                                                                                         ment plant
Flowrates are based on Energy Policy Act of 1992 maxima (US national code). Efficient equipment will mean lower greywater production and lower consumption)                                                                                                                                                                                          Bottom: Beneficial bacteria consuming solids in
                                                                                                                                                                                                                                                                                                                                                     wastewater (Lokus)
Note - water demand for flushing could be brought to zero with a combination of composting toilets and waterless urinals.

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                                                                        Advantages                             Disadvantages                                 System Examples           OPERATIONS AND MAINTENANCE CONSIDERATIONS
                                      Disinfection Systems
                                            Chlorine                    Low rst cost, no energy use,          Hazardous to maintenance staff, toxic          Brac                     System Comparison: Each system discussed above has different maintenance needs. In chemical systems (Brac), chemicals must
                                                                        standard practice in US                residues in treated water can harm plants
                                                                                                               and corrode copper pipes, not compatible
                                                                                                                                                                                       be administered on a strict schedule in controlled amounts. Exposure of maintenance personnel can be a health and safety issue.
                                                                                                               with biological ltration                                               The whole system must be cleaned out annually. In copper/silver ionization systems, metal rods must be cleaned regularly and
                                           Iodine                       Quick treatment, no energy use         Some chemical residue in efuent, more                                  replaced every 3-5 years. In ozone ionization systems and UV systems, annual UV lamp replacement is required. Ozone sys-
                                                                                                               costly than chlorine                                                    tems require annual replacement of some additional components. All physical filtration systems require regular cleanout. This is
                                           Ultraviolet light (UV)       No hazardous chemicals (safer          Sensitive to clogging (cannot operate with Pontos AquaCycle,            particularly critical when using UV disinfection. Systems with open biological treatment (Lokus) create a humid environment and
                                                                        operation, cleaner efuent),           any suspended solids), bacteria can persist if Lokus, Zenon
                                                                        standard practice in EU                UV is not strong enough
                                                                                                                                                                                       must be coupled with corrosion resistant materials and/or increased ventilation/dehumidification. Untreated gray water must not
                                           Ionization (Copper/Silver)   No hazardous chemicals in              Copper or silver present in efuent (toxic                              be allowed to sit untreated for more than a day as microbes may begin to multiply. Storage of water once treated is acceptable.
                                                                        operation                              bioaccumulation in receiving ecosystems),                               The packaged systems are equipped for immediate treatment.
                                                                                                               complex install and maintenance
                                           Ionization (Ozone)           No hazardous chemicals (safer          Cost, system complexity                                                 Planning for Operations and Maintenance: The operation of the proposed systems is highly automated, including remote moni-
                                                                        operation, cleaner efuent), highly
                                                                        effective                                                                                                      toring by the manufacturer and varying levels of routine onsite maintenance. As a precautionary measure against system mal-
                                                                                                                                                                                                                                                                                                                          Maintenance staff member at wastewater treat-
                                      Filtration Systems                                                                                                                               functioning, routine monitoring and surveillance of the system should be provided for (USEPA. 1992). An appropriate quality        ment site
                                            Physical                    Thorough particle removal              Can clog, requires frequent cleaning, does    Brac, Pontos              control program should be established at the onset of implementation of the gray water reuse system. Isliefson, 1998, suggests
                                                                                                               not break down pollutants                     AquaCycle, Lokus.         the following list of additional operations elements.
                                           Biological                   Aids in disinfection, breaks down      Some particles likely to remain without       Pontos AquaCycle,
                                                                        pollutants, less solid buildup, less   additional physical ltration                 Lokus, Zenon
                                                                                                                                                                                                “•Appropriate instrumentation and control systems for monitoring the treatment process performance
                                                                        cleaning required                                                                                              and disposal of waste products.
                                           Carbon                       Claries water, neutralizes odor       Likely to be insufcient as a single gray                                        •Appropriate alarms for process malfunctions.
                                                                                                               water lter, but excessive in-line for non-                                      •An appropriate quality assurance program to ensure adequate treatment and sampling protocol (in
                                                                                                               potable applications                                                    cluding facilities for sampling).
                                           Reverse Osmosis              Claries water, highly effective for   Likely to be insufcient as a single gray     Some Zenon systems
                                                                        removal of contaminants such as        water lter, but excessive in-line for non-                                      •Adequate emergency plumbing to discharge reclaimed water of unacceptable quality for re-treatment
                                                                        nitrogen                               potable applications                                                    or discharge to the sewer.
                                                                                                                                                                                                •Flexibility of piping and pumping facilities to permit rerouting of flows to alternative disposal facilities
                                                                                                                                                                                       under emergency conditions.
                                                                                                                       Most packaged gray water recycling systems employ multi-                 •Stand by power for essential treatment processes.
                                                                                                                       ple filtration systems in sequence followed by a disinfection            •Adequate operator training of permanent Office building maintenance staff to oversee the operations
                                                                                                                       treatment. Whatever the treatment process, the necessary        of the system and perform emergency maintenance and inspection.
                                                                                                                       end results are the same. Recommended limits for water                   •An effective preventative maintenance program.” - Isliefson, 1998
                                                                                                                       components for toilet flushing are described in the table at
                                                                                                                       left, from Isliefson, 2003.

From top: chlorine tablets, carbon,
ozonation process

14                                                                                                                                                                                                                                                                                                                                                                   15

                                            System access should be limited to certified trained plumbing specialists. Most manufacturers being evaluated offer training       gRAy wAteR coDe comPLiAnce
                                            courses to maintenance contractors and technical support staff with 5-15 year warranties. Manufacturer training and technical      The following section includes a few known approved gray water projects in Florida as precedent, and then highlights the various codes and
                                            support should be written into the assembly specifications. Authoring maintenance specifications will require experience with      regulations that cover the proposed Biscayne system.
                                            gray water recycling systems. In developing the maintenance specifications and contractor experience requirements, the design
                                            team should work with the local industry organization, Florida Onsite Wastewater Association, Inc. (FOWA) to develop an            RESIDENTIAL PRECEDENT
                                                                                                                                                                               While there are no known commercial gray water systems in Florida for indoor (flushing) reuse, there are a growing number of permitted            o       Alachua County Residence:
                                            O&M manual that meets all agency requirements. FOWA is closely involved with Department of Health’s most updated leg-
                                                                                                                                                                               systems on the residential scale. Most residential gray water systems supply landscape irrigation, and require minimal treatment, as the                      	 Permitting Official: Douglas
                                            islation, has training centers throughout Florida and a required certification program for Onsite Wastewater Treatment System      water is delivered directly to sub-surface irrigation and has little threat of coming in contact with humans. These Florida Plumbing Inspector-                    A. Tillery, Plans Examiner for
                                            installation & maintenance contractors. The early and continuous involvement of FOWA will provide continuity after construc-       approved systems can be found in Alachua County, Walton County, Brevard County, and West Palm Beach County. On April 24, 2007,
                                            tion at Biscayne, assuring the transition to system maintenance is smooth after the engineers, installers and manufacturers have                                                                                                                                                                      Walton County, Florida
                                                                                                                                                                               Florida’s Showcase Green Envirohome in Melbourne, Florida, became the first residence in the state to have a gray water reuse system installed                	 Permit Applicant: Dennis
                                            completed their work.                                                                                                              for in-home use to flush toilets. Brevard County’s Permitting and Enforcement Department approved this system based on the 2004 FBC                                Yasar (BRAC representative)
                                                                                                                                                                               plumbing code for gray water recycling systems. See the BRAC treatment system case study in this document for more information. Details           o       Walton County Residence:
                                            WATER QUALITY MONITORING                                                                                                           on these precedents are listed in the sidebar.                                                                                                                	 Permitting Official: Carol
                                                                                                                                                                                                                                                                                                                                                  Hurst, Alachua County
                                            Quality of both incoming gray water and outgoing reusable water should be continuously monitored to support proper                 COMMERCIAL PRECEDENT                                                                                                                                               Building Official Alachua
                                            operation and maintenance of the treatment system. Some of the proposed systems have real-time automated water quality             The Biscayne project can set a new precedent as the first large-scale gray water project in Florida. Examples of successful systems in other                       County Codes Enforcement,
                                                                                                                                                                               states and countries are numerous and will be discussed in the following section. Community scale reclaimed water systems have been
                                            monitoring built in, but if this is not offered, quality should be monitored manually on a monthly basis. Important monitor-                                                                                                                                                                          10 SW 2nd Ave. Gainesville,
                                                                                                                                                                               installed in many sensitive areas like the Florida Keys. Large-scale gray water systems use much the same technology as these full blackwater                      FL 32601(352) 338-3284
                                            ing parameters vary depending on the system employed. For chemical systems, chemical concentrations and pH need to be              treatment systems, and often exceed the same stringent codes that apply to them.
                                            closely controlled. For silver ionization systems, silver ion concentrations should be monitored. The same is true for ozone                                                                                                                                                                     	 Permit Applicant: Rhett Cork
                                            levels in ozone ionization systems and UV intensity in UV systems. In all systems, levels of key components such as BOD,                                                                                                                                                                              (Resident)
                                                                                                                                                                               AGENCY OVERVIEW                                                                                                                                   o       Brevard County Residence (in-home
                                            Nutrients, Suspended Solids Chemicals and Metals, and Bacteria should be monitored frequently for both incoming and exiting        Three agencies are primarily responsible for the permitting of gray water systems, the Department of Health (DOH), Department of                          reuse for flushing):
                                            water. We recommend that the Biscayne design team consider incorporated monitoring capabilities when evaluating system             Environmental Protection (DEP), and the Department of Building and Safety. Other departments, such as the Department of Environmental                         	 Permitting Official: Unkown,
                                            options.                                                                                                                           Resource Management (DERM) and the EPA, are sometimes involved, depending on the applications, for example DERM is only involved in                                Permitting and Enforcement
                                                                                                                                                                               the land application of gray water, and the EPA, only if the water reuse system is over 10,000 GPD. Most of the applicable codes are housed                        Department
                                                                                                                                                                               in the Florida Statutes and Florida Administrative Code (F.A.C.). The Building Codes stand alone, but references the F.A.C.                       o       West Palm Beach County
                                                                                                                                                                                                                                                                                                                                             	 System approval (not specific
                                                                                                                                                                               BUILDING & PLUMBING CODE                                                                                                                                           to a particular residence)
Top: examining water samples                                                                                                                                                   In 2004, Florida amended the Plumbing Code Section 301.3 to allow for gray water reuse in both landscape applications and toilet flushing.                    	 Permit Applicant: Dennis
Bottom: Wastewater before and after Zenon                                                                                                                                      To outline the gray water requirements, Appendix C was added to the plumbing code, and now serves as the primary document for                                      Yasar (BRAC representative)
biological treatment, Cauley Creek, GA                                                                                                                                         permitting grywater systems. In 2007, amendments to this original appendix were proposed and are pending approval. The changes do not
                                                                                                                                                                               affect the intent of the 2004 Appendix, but provide more detail and specification for designing systems. Like any technology, it is understood
                                                                                                                                                                               that the gray water recycling system must comply with all relevant building codes. Only the most relevant plumbing codes are addressed

                                                                                                                                                                               In the case of all of the known Florida permitted gray water projects, officials approved the systems based on their compliance with                  o     Appendix C Gray Water Recycling
                                                                                                                                                                               Appendix C of the Florida Building Code 2004 edition: Plumbing, Gray Water Recycling Systems. While most of the document addresses                          Systems. amending Section 301.3 of
                                                                                                                                                                               landscape application, Section C102 of the gray water code, discusses the requirements for reuse within the building for toilet flushing. The               the Plumbing Code.
                                                                                                                                                                               codes for this system are straightforward and the proposed system for Biscayne will comply with all of them. Some of the critical code
                                                                                                                                                                               excerpts are listed below and the entire Appendix C is appended to this document for reference and includes schematic diagrams.

                                                                                                                                                                               FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION
                                                                                                                                                                               When it comes to water quality and health issues, code administration is complex. In 1995, the Department of Environmental Protection
16                                                                                                                                                                                                                                                                                                                                                                           17

                                                           entered into an Interagency Agreement with the Department of Health to coordinate the regulation of onsite sewage treatment and                      referenced for reuse in toilets. In other parts of this section, there are clauses saying “the department may waive or alter the compliance levels”      For purposes of the Florida Wastewater Code:
                                                           disposal systems (OSTDS) and septage management facilities and disposal sites, to try to coordinate agency overlap in this area. DEP                 for various reasons, if it is not seen as an environmental concern. The design team would like to work with the DOH to understand what                   “Domestic Wastewater” includes waste from
                                                           became responsible for CHAPTER 62-600 F.A.C Series and local programs under Chapter 403, Florida Statutes (F.S.), while DOH and its                  appropriate water quality levels are needed for toilet reuse, and assure our system meets these.                                                         homes, portable toilets, holding tanks, boats
                                                           County Health Department (CHD) offices became responsible for administering Chapter 64E-6, F.A.C. series and Chapter 381, F.S. While                                                                                                                                                                          and marinas and even wastewater from certain
                                                                                                                                                                                                                                                                                                                                                                         commercial and industrial establishments.
                                                           the DEP is responsible for regulating large-scale treatment systems and municipal water reclamation, the DOH is responsible for health               In addition to gray water reuse in the building, Biscayne Landing proposes to reuse air conditioner condensate to irrigate. While the quality of
                                                                                                                                                                                                                                                                                                                                                                         “Commercial Wastewater” is similar to domestic,
Codes Regulating Gray Water                                concerns, human contact and traditional residential and commercial onsite wastewater treatment systems (i.e. septic tanks).                          condensate is extremely high (nearly distilled quality), the water quality and jurisdiction of cooling tower & air conditioner condensate is also        only stronger, such as wastewater from food service
                                                                                                                                                                                                                unclear. As the project team investigates the reuse of Cooling Tower blowdown and AC condensate for other parts of the project. While                    operations (e.g., restaurants, school cafeterias,
62-610.451 Minimum System Size:                            While this effort resolved many conventional onsite reuse questions, it is not clear from these descriptions under which purview the                 many states consider these sources “domestic wastwater,” some members of DERM believe that it might fall under “industrial wastewater”.                  etc.), commercial laundries with no more than
While most water reuse systems need to have a
                                                           gray water system falls. It is also unclear whether both DOH and DEP water quality standards are required. Because the incorporation                 If you read the distinction between these from DEP, it is unclear into which section mechanical wastewater from an office building falls                 four washing machines, animal holding facilities
minimum size of .1 MGD,
Chapter 62-610.451 section (3) states “ A minimum          of gray water into the Florida Plumbing Code is so new, a few “gray” areas (not to be confused with gray water), or open ended codes                 Resolution on this distinction is important to proceeding. Questions include:                                                                            (e.g., commercial kennels, veterinary hospitals, and
system size is not required if reclaimed water will be     leave negotiation up to the permitting agency. Below we list a variety of these outstanding questions, predominatly regarding water quality                                                                                                                                                                   animal grooming facilities), and beauty salons.
used only for toilet flushing or fire protection”          standards and the relevant codes where applicable. We hope this document will initiate collaborative decision-making amongst the                            What is the appropriate process for verifying the quality of this water for reuse?                                                                Please note that “Commercial Wastewater” is
                                                           departments and the design team to answer these questions.                                                                                                  Which agencies would be involved in review and ultimately approving these rulings?                                                                not necessarily synonymous with wastewater
62-610.476 (1) Toilet Flushing and Fire Protection:                                                                                                                                                                                                                                                                                                                      from commercial businesses. All other wastewater,
Reclaimed water may be used for toilet flushing                                                                                                                                                                                                                                                                                                                          including those that are toxic and/or hazardous,
in commercial or industrial facilities or buildings.                   The Interagency Agreement, 2001, goes on to say that “Onsite Sewage Treatment and Disposal System (OSTDS) - shall be as                  FLORIDA DEPARTMENT OF HEALTH                                                                                                                             is considered “Industrial Wastewater,” including
Reclaimed water may be used for toilet flushing in                      defined in Section 381.0065, F.S. This term does not include packaged sewage treatment facilities and other treatment works             In Florida, gray water is referenced in many codes, but officially defined under Title XXIX, Florida Statutes, Public Health Chapter 381.0065:           wastewater from dairies, food processing plants,
motels, hotels, apartment buildings, and condomini-
                                                                        regulated under Chapter 403, F.S. Further, the term does not include any system that provides for other than subsurface effluent        Onsite Sewage treatment and disposal systems, as “that part of ‘domestic sewage’ that is not blackwater, including the waste from the bath,              slaughterhouses, funeral homes, car washes, and
ums where the individual guests or residents do not
have access to the plumbing system for repairs or                       disposal or which has open tanks or open treatment units”. Is a gray water system classified as a packaged treatment facility           lavatory, laundry, and sink, except kitchen sink waste.” In the DOH and DEP, domestic and commercial are not used the same as manor as other             commercial laundries with more than four washing
modifications. Reclaimed water pipes shall be color                    (under the purview of DEP), or is it considered to be an OSTDS (and thus under the purview of DOH)?                                      forms of building [See sidebar wastewater distinctions], so waste water from commercial buildings is actually “domestic waste”. The primary              machines. (INTERAGENCY AGREEMENT, 2001)
coded The engineering report shall document cross-                                                                                                                                                              code series of the DOH addressing gray water use is CHAPTER 64E-6, FLORIDA ADMINISTRATIVE CODE “STANDARDS FOR ONSITE
connection control measures and controls on facility                                                                                                                                                                                                                                                                                                                     Rule 64E-6.013(4).
                                                                       CHAPTER 62-600 F.A.C. - Reuse of reclaimed water and land application                                                                    SEWAGE TREATMENT AND DISPOSAL SYSTEMS” [See Sidebar for specific code language]. In addition to the Appendix C, CHAPTER 64E-6
operation sufficient to ensure reliable production of                                                                                                                                                                                                                                                                                                                    When a separate system is installed to dispose
reclaimed water of suitable quality.                                   While there are many codes and limitations pertaining to the reuse on land application in 62-610 series (DEP), only one sub-             serves as the primary gray water code, and the Biscyane project will be designed to meet all of these codes.
                                                                                                                                                                                                                                                                                                                                                                         of graywater, the retention tank for such systems
                                                                       section of this chapter addresses indoor reuse: “62-610.476 Toilet Flushing and Fire Protection.” Critical code criteria are listed in
                                                                                                                                                                                                                                                                                                                                                                         shall meet certain design standards as specified
62-610.476 F.A.C.: Toilet Flushing and Fire Protection:                the sidebar and the proposed system for Biscayne will need to comply with all of them. The design team needs to know which               DERM (Department of Environmental Resources)
1(b): If reclaimed water will be used only for toilet                                                                                                                                                                                                                                                                                                                    in Rule 64E-6.008(3): The minimum effective
                                                                       DOH department and officials we would work with to develop the level of reliability and operation controls needed for the                The primary concerns of DERM include the exposure and contact of gray water with the natural environment. If gray water is used in a                     capacity of the graywater retention tank shall
flushing, the Department shall approve alternative
levels of reliability, operation controls, and operator                toilet flushing system.                                                                                                                  “closed loop” system within the building and ultimately discharged to the sewer, there are little or no concerns from the standpoint of DERM.            be 250 gallons, with such system receiving not
attendance if the applicant provides an affirmative                                                                                                                                                             Because our system will discharge to the sewer, we have omitted a review of the DERM codes related to gray water reuse.                                  more than 75 gallons of flow per day.
demonstration in the engineering report that alterna-                  CHAPTER 403.086 F.A.C.: Sewage disposal facilities; advanced and secondary waste treatment. This section pertains to the
tive controls will provide controls on reclaimed water                                                                                                                                                                                                                                                                                                                   Where separate gray water and blackwater
                                                                       quality of water required of onsite waste treatment systems to discharge to the environment under varying conditions. The water          PeRmitting PRoceSS
production equivalent to the full requirements of Part                                                                                                                                                                                                                                                                                                                   systems are used, the size of the blackwater
III of Chapter 62-610, F.A.C., and the engineering re-                 quality standards established in Section 4 of this chapter define “advanced waste treatment” as that treatment which will provide
                                                                       a reclaimed water product that:                                                                                                                                                                                                                                                                   system can be reduced by not more than 25%.
port presents reasonable assurances that public health                                                                                                                                                          PROGRESS TO DATE
will be protected.                                                                                                                                                                                                                                                                                                                                                       10D-6.055
                                                                                                                                                                                                                The project team has hired Rana Creek, an Ecological Design and Water Conservation consulting firm from California, to help facilitate
                                                                               - Contains not more, on a permitted annual average basis, than the following concentrations:                                     the design and permitting of the gray water system. Rana Creek, along with William Gonzalez, the plumbing engineer, and members of the                   (k) All gray water tanks distributed by the state
                                                                                     Biochemical Oxygen Demand (CBOD5) 5mg/l                                                                                    architecture team, met with various permitting officials the week of August 20th. The team introduced officials to the Biscayne project, assess          shall be approved for use by the department
                                                                                     Suspended Solids 5mg/l                                                                                                     the feasibility of gray water reuse within the building, and gain initial feedback from permitting agencies. Below is a recap of those first meetings.   prior to being installed. Such approval shall
                                                                                     Total Nitrogen, expressed as N 3mg/l                                                                                                                                                                                                                                                be obtained only after the manufacturer of
                                                                                     Total Phosphorus, expressed as P 1mg/l                                                                                     DOH Conference Call: On August 20nd, Brent Bucknum from Rana Creek spoke with Samir Elmir. While the could not meet in person, Elmir                     a specific model has submitted engineering
                                                                                                                                                                                                                gave his support to the gray water project, provided it meets all relevant codes, and said he would help raise awareness for the project, and            designs of the tank.
                                                                               - Has received high-level disinfection, as defined by rule of the department.                                                                                                                                                                                                             (4) Gray water retention tanks - when a
                                                                                                                                                                                                                help organize meetings with the Perkins if needed. In further investigation, we discovered we needed to be working with the City of North
                                                                                                                                                                                                                                                                                                                                                                         separate system is installed to dispose of gray
                                                                                                                                                                                                                Miami to drive the permitting process rather than the County.
                                                          While the strict water quality requirements are understood for onsite system which will eventually discharge to water bodies,
                                                          aquifer or ground application, these standards ultra-low nutrient standards are not necessary for gray water that will be                             DERM Meeting: On August 21nd we met with DERM officials, Harvey Koetki and Agustin Socarras.
                                                          discharged into the public sewer. While complete disinfection is understood, it is unclear which water quality standard should be                     In the meeting, we gained an understanding of the different DERM concerns regarding gray water reuse, predominately regarding
18                                                                                                                                                                                                                                                                                                                                                                                                                        19

water, the retention tank for such system shall        land application. Koetki, wellfield protection specialist, addressed the groundwater contamination concerns, brownfield concerns       INVOLVED OFFICIALS (NOT A COMPLETE LIST)
meet the following minimum design standards:           and wetland habitat concerns. Socarras addressed the issues with cross-contamination of gray water, septic, sewer and/or potable
a) the minimum effective capacity shall be as                                                                                                                                                 Maribel Balbin                                           Jorge Gamoneda
specified in Rule 10D-6.048(3). Liquid depth
                                                       water sources
                                                                                                                                                                                              Water Conservation Manager                               Code Compliance Specialist - Plumbing
shall be at least 30 inches; and b) retention
                                                                                                                                                                                              Miami-Dade Water and Sewer Department.                   Miami-Dade County
tanks shall be baffled and vented as specified         City of North Miami Meeting: On August 22nd, Brent Bucknum, William Gonzalez, and Anne Cotter, project manager from
in the septic tank construction standards found                                                                                                                                               Tel: (786) 552-8149                                      140 W. Flagler Street, Suite 1603
                                                       Arquitectonica, met with John Jackson Chief Building Inspector & Robert Hernandez, Chief Plumbing Inspector. While Jackson                                        Miami, Florida 33130
elsewhere in the section provided that an inlet
                                                       had not yet encountered gray water systems, he was intrigued by the goals of water conservation and wanted more information,                                                                    Phone: (305) 375-2901, ext. 4671
tee, ell, or baffle shall be provided for gray water
tanks.                                                 case studies and examples of built systems in Florida and other states to understand their viability. Jackson’s request was the        Department of Environmental Resources Management         Fax: (305) 375-2908
                                                       motivation for this document. Jackson stated that while the permitting process would be handled through the North Miami                (305) 372-6500                                 
10D-6.048(3) – Retention Tank                          Building Department, alternative systems such as this gray water system would be taken to the county level for review and
When a separate system is installed to dispose         approval, most likely George Gamoneda, Chief Building Code Compliance Official.                                                                Harvey Koetki                                    City of North Miami
of gray water, the retention tank for such                                                                                                                                                            Pollution Control, DERM                          776 NE 125 Street.
system shall meet the following minimum design
                                                       Plumbers Union Hall Meeting: On August 23nd , following our meeting in North Miami, design team members met with George                        (305) 372-6516 (or 6789)                         North Miami, FL 33161
a) the minimum effective capacity shall be as          Gamoneda, before a monthly meeting with all of the Plumbing Inspector’s from the un-incorporated cities of Miami-Dade County.
specified in Rule 10D-6.048(3).                                                                                                                                                                       Agustin Socarras, P.E.                                    Robert Hernandez, P.E.
                                                       Brent Bucknum, then presented the state of gray water technology to the Inspector’s meeting and fielded questions. While
Liquid depth shall be at least 30 inches;                                                                                                                                                             Water and Wastewater Engineering Section, DERM            Chief Plumbing Inspector
                                                       Gamoneda supported the gray water system, his primary concern was the discrepancy between the Appendix C, acceptance                           Telephone (305) 372-6899                                  305-893-6511
Retention tanks shall be baffled and vented
as specified in the septic tank construction           of the gray water for flushing and restrictions in the Florida Administrative Code limiting the use of gay water indoors where
standards found elsewhere in the section               occupants had access to the plumbing. In reviewing the 64E-6, F.A.C. this was resolved, in that the restriction was from residential   Samir Elmir, P.E.                                                 John H. Jackson, P.E.
provided that an inlet tee, ell, or baffle shall be    facilities, not commercial facilities (see sidebar for code language). During the plumbing inspectors meeting, gray water system       Environmental Administrator                                       Building Official
provided for graywater tanks.                          concepts were received well and the growing demand was discussed. Most questions and concerns pertained to the verification            Miami-Dade County Health Dept./Environmental Health               305-893-6511
Source: State of Florida, Department of Health.
                                                       of certified installation of the systems by qualified professionals, the operation and maintenance of systems and the ability for      Business Address: 1725 NW 167 St. Miami, FL 33056
3 March 1998. Standards for on-site sewage             occupants in residential applications to have access to the system. The first two concerns can be addressed in the development         Business: (305) 623-3500                                 Gary Perkins
treatment and disposal systems. Chapter 64E–6,         of stringent experience standards in the final specifications for the assembly of the system and a detailed Operations and             Business 2: (305) 623-3595                               Plumbing Division Director
p. 31. Florida Administrative Code.                    Maintenance Manual, which are both intended to be in the project documentation. The residential concern, while valid, does not         Business Fax: (305) 623-3502                             Building Dept. Permitting and Inspection Center
and                                                                                                                                                                    11805 SW 26 St. Room 137
                                                       apply to this commercial application, where the gray water treatment system will be contained and accessed only by a licensed
wqslibrary/fl/fl-403.086.html                                                                                                                                                                                                                          Miami, FL 33175-2474
                                                       maintenance contractor.                                                                                                                                                                         (786) 315-2084

                                                       Mayors Meeting: On September 12th, team members from Arquitectonica met with the Executive Assistant to the County
                                                       Manager, Henry F. Sori, to discuss green measures including water conservation. Sori assigned Suzanne Troner and Maribel
                                                       Balbin as the primary agency contacts for negotiating gray water reuse questions between departments and spearheading the
                                                       coordination with the Biscayne Landing project team. Brent Bucknum of Rana Creek and Anne Cotter of Arquitectonica will be
                                                       meeting with these contacts to further discuss permitting the project.

                                                       neXt StePS

                                                       Project Documentation, Outstanding Code Questions and Approval Process: The project team is now developing the
                                                       construction drawings and engineering specifications for the system. We are working with the manufacturers to ensure
                                                       compliance with code and will need to be in contact with the permitting agencies to resolve the open-ended questions in the
                                                       code discussed above. Brent Bucknum will work with Anne Cotter to develop a roadmap to permitting and approval.
20                                                                                                                                                                                                                                                                                                       21

                               RESOURCES                                                                                                                 COMPANY OVER VIEW
                                                                                                                                                         Rana Creek, located in Carmel Valley, California, has been incorporated since April 1, 1997. We have a staff of twenty
                               Brac Systems                                                                                                              professional ecologists, biologists, landscape designers, civil engineers, researchers, contractors, horticulturalists, and
                               Website:                                                                                 habitat restoration specialists that is augmented by a network of expert consultants. Our firm is rooted in the tradi-
                                                                                                                                                         tions of science and ecology, offering a broad range of environmental planning, ecological design/build and AEC services
                                                                                                                                                         dedicated to sustainability.

                               Lokus                                                                                                                     RANA CREEK LIVING ARCHITECTURE
                               Website:                                                                            Rana Creek Living Architecture is redefining the built environment by encouraging biodiversity as part of site and struc-
                                                                                                                                                         ture. Our innovative models for habitat restoration focus on the purification and reuse of water. We design for the
                               GE Zenon                                                                                                                  biodiversity of site and foster ecological systems that engage vegetated surfaces as protective, breathing, and water pro-
                               Website:                                                                                            cessing membranes. Rana Creek’s project involvement ranges from conceptual design to the complete development
                                                                                                                                                         of construction documents, the propagation of plants, living roof installation and ecological maintenance and monitor-
                               Doug Thompson, Cory Schneider, Mark Murphy, ZENON Environmental Inc: Immersed Membrane Bioreactors for Water              ing. Rana Creek’s unique and considered approach ensures ecological integration and produces quality solutions and
                                      Reuse: Summary of Five Years’ Experience, 2003                                                                     results for both landscapes and built environments.
                               Diana Isliefson, University of Manitoba: Protocols for Pre-design Assessment of Greywater Reuse Retrofit in Urban Rede-
                                                                                                                                                         BUILDING INTEGRATED WATER MANAGEMENT
                                        velopment: An Opportunity/Constraint Analysis Method for Existing Buildings, 1998
                                                                                                                                                         Inherent in all our designs is an understanding of the ecological and economic value of water. As a part of the growing
                               Interagency Agreement Between the Department of Environmental Protection and the Department of Health for Onsite          field of onsite water reuse, Rana Creek has helped to form a BIWM committee between the National Onsite Waste-
                                       Sewage Treatment and Disposal Systems, September 10, 2001                                                         water Recycling Association (NOWRA) and Green Roofs for Healthy Cities, two industry organizations, to conduct
                                                                                                                                                         research and develop national policy for Building Integrated Water Management. Our vegetated and engineered
                               U.S. EPA Design Manual: : Onsite Wastewater Treatment and Disposal Systems 1980                                           solutions to water management minimize the impact of the built environment by integrating it with natural hydrologic
                                                                                                                                                         cycles as well as building function. Storm and gray water collection, storage, and reuse systems are integrated into the
                               Vinita Chanan et al, Institute for Sustainable Futures and Sydney Water Corporation: Sustainable Water Management in      project design to close the loop of water flow throughout each site. Rana Creek staff have designed multiple permit-
                                       Commercial Office Buildings:                          ted gray water, black water and constructed wetland systems including the first permitted systems in several counties
                                                                                                                                                         in California. We are designing or have designed additional projects in Los Angeles, San Diego, San Francisco, Boston,
                               Water Resources Engineering, Inc. (prepared for the Partnership for Advancing Technology in Housing, US Department of     and Vancouver. We have experience with high-tech mechanical treatment systems, low-tech gravity flow and branched
                                      Housing and Urban Development, Office of Policy Development and Research): Water Conservation: Overview
                                                                                                                                                         drain systems, and innovative solutions such as treatment wetlands built on roofs. Issues of soil percolation rates, sewer
                                      of Retrofit Strategies, A Guide for Apartment Owners and Managers, 2002
                                                                                                                                                         backup fail-safes, pre-filtration, storage, pumping, and irrigation applications are within our expertise and experience.
                               Water Quality Guideline and Water Monitoring Tools for Residential Water Reuse Systems, 1999                              We have designed projects ranging from small residential to large municipal building scale, and will customize solutions
                                                                                                                                                         to fit into the program of each project. Beyond providing technical support and system design services, we are well-
                               Wilson: Using Greywater for Landscape Irrigation, 1995, cited in Isliefson, 1998                                          equipped to guide projects through the permitting process.

22                                                                                                                                                                                                                                                                                     23

                                                                                                                                                       II. Recommended Treatment by Variable
                               I. Gray Water Characteristics by Source                                                                                 Types of Treatment               Variable
                               Water Source                     Characteristics
                               ___________________________________________________________________________________________                             Aeration                                Odor, Organic matter, Oxygen
                                                                                                                                                                                               demand, and pH
                               Automatic Clothes Washer       Bleach, Foam, High pH, Hot water, Nitrate, Oil and Grease, Oxygen demand,
                                                              Phosphate, Salinity, Soaps, Sodium, Suspended solids, and Turbidity                      Alum                                    Soaps, and Turbidity

                                                                                                                                                       Carbon filtration                       Odor
                               Automatic Dish Washer                 Bacteria, Foam, Food particles, High pH, Hot water, Odor, Oil and grease,         Chlorination                            Bacteria, and Odor
                                                                     Organic matter, Oxygen demand, Salinity, Soaps, Suspended solids, and Turbidity
                                                                                                                                                       Crop filtration                         Bacteria, Food particles, Suspended
                                                                                                                                                                                               solids, and Turbidity
                               Bath tub and shower                   Bacteria, Hair, Hot water, Odor, Oil and grease, Oxygen demand,
                                                                     Soaps, Suspended solids, and Turbidity                                            Crop uptake                             Nitrate, Phosphate, Soaps,
                                                                                                                                                                                               and Sodium
                               Evaporative Cooler                    Salinity                                                                          Dilution                                Hot water, Nitrate, pH, Phosphate,
                                                                                                                                                                                               Salinity, and Sodium
                               Sinks, including kitchen              Bacteria, Food particles, Hot water, Odor, Oil and grease, Organic matter,
                                                                     Oxygen demand, Soaps, Suspended solids, and Turbidity                             Filtration                              Food particles, Oil and grease,
                                                                                                                                                                                               Organic matter, Soaps, Suspended
                                                                                                                                                                                               solids, and Turbidity
                               Swimming Pool                         Chlorine, and Salinity
                                                                                                                                                       Flotation                               Oil and grease

                                                                                                                                                       Hydrogen peroxide                       Bacteria, and Odor

                                                                                                                                                       Lime                                    Bacteria, Odor, and Sodium

                                                                                                                                                       Settling                                Foam, Food particles, Hot water,
                                                                                                                                                                                               Organic matter, Oxygen demand,
                                                                                                                                                                                               and Suspended solids

                                                                                                                                                       Soil filtration                         Bacteria, Bleach, Chlorine, Foam,
                                                                                                                                                                                               Food particles, Organic matter, Oxygen
                                                                                                                                                                                               demand, Suspended solids, and Turbidity

                                                                                                                                                       Soil uptake                             Nitrate, Phosphate, Soaps, and Sodium

                                                                                                                                                       Storage                                 Foam, Food particles, Hot water, Organic
                                                                                                                                                                                               matter, Oxygen demand, pH, and
                                                                                                                                                                                               Suspended solids                                  25

V. Appendix C of the Florida Plumbing Code

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