REPORT TO ENVIRONMENT City of Kingston Ontario by alicejenny

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									                  CITY OF KINGSTON
                  REPORT TO ENVIRONMENT,
                  INFRASTRUCTURE AND TRANSPORTATION
                  POLICIES COMMITTEE
                                                                       Report No.: EITP-12-003

TO:                           Chair and Members of the Environment, Infrastructure and
                              Transportation Policies Committee
FROM:                         Jim Keech, President and CEO
RESOURCE STAFF:               Jim Miller, Director, Utility Engineering
                              Mike Fischer, Utilities Engineer
DATE OF MEETING:              December 13, 2011
SUBJECT:                      Sanitary Sewer Back Ups – Flooding
                              Private Side Extraneous Flow Reduction Program


EXECUTIVE SUMMARY:

A short-duration yet very intense rainfall fell over much of the City of Kingston on July 29, 2011.
The event caused widespread drainage problems which ultimately resulted in sanitary and
combined sewage overflows to the environment, severe street level flooding in some areas as
well as widespread basement flooding. This Report provides details on the event, the outcome
and builds on Report No. EITP-11-027 by recommending a multi-pronged approach focused on
source-control measures and mitigative programs to reduce the likelihood of future flooding of
private property.

It should be noted that the proposals in this report are not all encompassing and while focused
both on private and public-side extraneous flow issues, staff expect to return to Committee and
Council in 2012 with a second report outlining other targeted areas for potential further
improvements to the municipal sanitary sewage collection and conveyance system.

RECOMMENDATION:

It is recommended that Council for the City of Kingston approve the following programs and
actions:




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   1. The „Private-Side Extraneous Flow Reduction Program‟, consisting of a Preventative
      Plumbing Program, Downspout Disconnection Program and Sump Pump Disconnection
      Program, be approved for development and implementation starting in 2012.
   2. The „Public–Side Extraneous Flow Reduction Program‟.
   3. The principle and adoption of suitable practices to ensure, where possible, that
      elimination of extraneous flows to the sanitary system is maximized as part of any capital
      reconstruction affecting the sanitary system.
   4. That application of mandatory backflow prevention devices in all new homes be reviewed
      and reported back to Council by staff by 2012.
   5. The Public Education Package on basement flooding.
   6. The proactive enforcement of the Sewer Use By-Law No. 2008-192 as it relates to illegal
      connections and the elimination of extraneous flows that contribute to basement flooding.
   7. A review of existing policies and practices to determine their collective effectiveness or
      shortcomings in supporting activities to reduce flooding of all kinds, including both
      sewage backups and storm- and ground-water flooding.

AUTHORIZING SIGNATURES:

ORIGINAL SIGNED BY PRESIDENT &
________________________________________ CEO, UTILITIES KINGSTON
Jim Keech, President and CEO, Utilities Kingston
  ORIGINAL SIGNED BY CHIEF ADMINISTRATIVE OFFICER
_______________________________________
Gerard Hunt, Chief Administrative Officer


CONSULTATION WITH THE FOLLOWING COMMISSIONERS:

Cynthia Beach, Sustainability & Growth                 N/R

Lanie Hurdle, Community Services                       N/R

Denis Leger, Transportation, Properties &
                                                       N/R
Emergency Services

(N/R indicates consultation not required)




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OPTIONS/DISCUSSION:

Event Details
The rainfall event of July 29, 2011 was a short-duration yet very severe rainfall event in terms of
sustained intensity that fell over most of the City of Kingston. Three available rain gauges
measured the total precipitation for the day as per Table 1. Aside from slightly less precipitation
recorded at the airport, both River Street and Ravensview recorded approximately the same
rainfall in both locations.

TABLE 1. CITY-WIDE RAINFALL TOTALS FOR JULY 29, 2011

 Location                                             Total Rainfall (mm)
 Environment Canada (Airport)                                71.4
 Utilities Kingston (River Street Pump Station)              94.3
 Utilities Kingston (Ravensview WWTP)                        92.1

A statistical analysis was undertaken on the data available from the River Street rain gauge for
the purpose of determining the probability of the event. Statistics were generated for the event
itself and compared to available „intensity-duration-frequency‟ data for the River Street Pump
Station weather station which has roughly 60 years of reliable data (see Figure 1).

FIGURE 1. JULY 29, 2011 EVENT STATISTICAL ANALYSIS




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The parallel thinner lines shown in Figure 1 represent the statistics for River St, while the red
heavy line represents the actual July 29, 2011 event. In the Figure legend, the acronym „TR‟
refers to „Return Period‟. What can be seen from this figure is that for the 1, 2 and 6 hour
duration statistics, the event of July 29, 2011 far exceeded the estimated “100 year” event.
While mathematically the data can be used to extrapolate to 100‟s and 1,000‟s of year return
periods, the numbers would be statistically meaningless as they are based on a mere 60 years
of data. Nonetheless, extrapolation reveals a 2-hour return period in the order of 5,200 years.
Suffice to say it was a very extreme event that statistically speaking has a very low probability of
occurrence. Relative to available data, the event of July 29, 2011 can reasonably be considered
a „statistical outlier‟.

Worthwhile noting is that a discussion of rainfall in terms of “return period” contains inherent
terminology that leads to a misunderstanding of statistics. For example, what a „100- year
event‟ truly means is not that the event will only happen once in 100 years, but that the event
has a 1% probability of happening any year, from year to year, regardless of what happened the
previous year. As such, extreme events can happen within consecutive years, or even within a
single year. The event of July 29, 2011 simply had a very low chance of occurring, based on
our knowledge of area rainfall from 60 years of data. However, 60 years is not a very long
record, and it is conceivable that the apparent increase in intense events is a result of climate
change, although climatologists are unable to clearly define what the results of climate change
are expected to be, from place to place. Needless to say, a rainfall event that may currently
appear as a statistical outlier, such as that of July 29, 2011, may in fact become a regular event
given the uncertainties of climate change. Climate change is an unknown risk.

The following bullets summarize the analysis of the event:
       According to the River Street rain gauge, 94.3mm of rain fell over a duration of roughly 3
       hours and 50 minutes, of which over 65mm fell in just 60 minutes. The majority fell within
       2 hours (90.6mm).
       The event was abnormally severe and had a very low probability of occurrence (relative
       to the available 60 years of data).

Outcome
The outcome of the event was likely evident to most Kingston residents and has been well
documented in the media and within previous discussions with staff and City Council. The
following is a very general, yet non-exhaustive list of the outcomes of this event.




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        Surface flooding. With relatively dry hard ground and due to the severity of the rainfall,
        surface flooding was widespread throughout a number of areas in the City, many of
        which had never been subject to flooding in recent history. Some of the areas included
        the following:

        o On King Street, at the foot of Collingwood Street. This localized low-lying area has a
          history of surface flooding.
        o On Sir John A. MacDonald Boulevard, just north of Princess Street.
        o On Barrack Street, just east of Wellington Street.
        o Ontario Street, just north of Princess Street.

        Inundation and surcharging of utilities and services. The storm event generally
        resulted in the surcharging or inundation of the majority of underground services.

        o Storm systems were generally surcharged and considered to be 100% full, in many
          areas of the City. Some areas were surcharged to the surface. This includes the
          minor system (pipes) and the major system (roads). Note that the storm minor
          system (pipes) is designed to accommodate roughly a „2- to 5-year event‟. The
          system generally functioned as designed, with some local surface areas that were
          unable to drain quickly enough.
        o Combined sewers were generally surcharged, in some cases to the surface, and
          considered to be 100% full in many areas of the combined sewer service area,
          generally located downtown. This resulted in displacement of a significant number of
          manhole covers which were lifted due to the hydraulic pressure from water below.
          Note that combined systems were mostly constructed in the 1950‟s to the 1980‟s and
          also designed for roughly a 5-year event plus an allowance for sewage flows. It is
          believed that the system functioned as designed.
        o Sanitary sewers were generally surcharged in many areas. Sanitary sewers
          responded considerably to the rapid inflow of „extraneous flows 1‟ sufficient to cause
          basement backups in a large number of homes across the City, mainly focused within

1
  Extraneous Flows, otherwise known as ‘Inflow and Infiltration’ or I&I for short, are otherwise clean ground- and surface-
water flows that are making their way into the sanitary sewer system. Such flows enter the system by a number of pathways,
including cracks & leaks in the sewers (mains & laterals), cross-connections to the storm sewer system, and illegal
connections such as sump-pumps, foundation drains and rooftop drainage downspouts.




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       the Central portion of the City of Kingston. Sanitary systems are designed for sewage
       flows plus an allowance for some extraneous flows. While the system generally
       operated as designed, the occurrence of sanitary sewer backups as caused by the
       event clearly indicates that extraneous flows far exceeded the design allowance
       (which is a Ministry of Environment standard).

    Combined sewer overflows

    o There are a number of facilities and locations within the sewer mains that are subject
      to bypassing of flows to the environment for the protection of basements, services and
      other low-lying features. Most facilities and overflows were bypassing and the
      recorded quantity was in the order of 180,000 m3. However, as many sewers were
      surcharging to the surface and pushing off manhole lids, the quantity that overflowed
      via surface routes is not included in this total since it could not be estimated. While
      this was a very significant event, the quantity that could be measured did not exceed
      the recorded bypass volume of March 5/6, 2011, mainly due to the short duration.
      One thing that can be said is that bypass capacity of overflow points was unable to
      keep up with the inflow of water into the system. From a certain perspective therefore,
      the bypassing features of the sewer systems (where available), did not function as
      designed and were overwhelmed.

    Basement flooding

    o A large number of basement floods have been documented since the July 29, 2011
      event and reports continue to be received by Utilities Kingston and City of Kingston
      staff. As of November 16, 2011, the number stood at 323 reports, the vast majority of
      which are located within the central portion of the City of Kingston. The nature of
      flooding reports is of many varieties, including both sanitary & combined sewer
      backups and ground- & surface-water flooding, two generalized categories with
      notably differing inherent health, safety, insurance and repair implications. Figure 2
      illustrates areas where concentrated basement flooding reports were received but
      does not show individual properties that reported, nor does it show the one-off reports
      scattered about the City (to protect the privacy of individual homeowners). It is
      unknown how many additional flooded basements may have occurred and what
      percentage the reports received represent relative to the total.




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       Facility Overload

       o During conditions such as those caused by the July 29th, 2011 rainfall event, the
         majority of pumping stations that are part of the sewage collection system were either
         operating at full capacity, or simply overwhelmed resulting in bypass. In certain
         locations, the receiver facilities may be overwhelmed resulting in damage. For
         example, during the July 29th, 2011 event, one of the wastewater treatment plants
         was mere minutes away from sustaining severe damage from the excess flows
         entering the facility due to the contributing pump stations operating at full capacity.
         This highlights the fact that the system, as a whole, was operating at full capacity and
         there was no additional ability to bypass additional flows or pump more.

An additional observation is noteworthy at this point. Design and engineering of any structure,
whether it is a building, a utility, or a bridge, is based on sound engineering principles and the
use of design parameters that are considered reasonable, given a level of safety commensurate
with the inherent risk of failure. Any feature that is designed based on a highly variable
parameter, such as weather, will inherently have a level of risk associated with it, and that is the
risk of an event occurring that was considered to have a reasonably unlikely chance of
occurring. As such, and in particular due to the increased uncertainty associated with climate
change, there will always be a chance that an event occurs that exceeds the design capacity of
the feature. The point worthy of emphasis is that it is nearly impossible to create a storm and
sanitary drainage system that is capable of offering zero risk of flooding, and attempting to do so
would be overwhelmingly expensive and generally against best practice.




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     FIGURE 2. CONCENTRATED FLOODING AREAS
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Underlying Causes
As this report to Council is primarily focused on basement flooding due to sewer backup, the
discussion will focus on the mechanisms that contribute to this problem, rather than the
mechanisms contributing to storm- and ground-water flooding.

A great deal of information has already been prepared and presented on the topic of basement
flooding, as a result of the March 5/6, 2011 rain-on-snowmelt event. This event and its
consequences were discussed in detail in the Information Report No. EITP-11-027 dated August
9, 2011.

In general, the following bullets provide a brief summary of Report No. EITP-11-027

      Spatial concentration of basement backups were categorized in three general scales,
      including;
      o Lot-Level or ‘micro-scale’ – one-off or unclustered backup reports, generally
        believed to be due to property-specific lateral, drainage or plumbing issues.
      o Somewhat concentrated flooding events or ‘meso-scale’ – multiple homes
        clustered together in a concentrated area, generally due to localized extraneous flows
        and/or impairment in sewer mains.
      o Concentrated flooding events or ‘macro-scale’ – multiple clusters of homes or
        neighbourhoods in proximity or with a common service feature, such as a pump
        station or trunk sewer, generally due to wide-spread extraneous flows of impairment
        in service.

      The scale is worthy of note as it generally provides an indication of the ability of Utilities
      Kingston and/or the City of Kingston to pursue the causes and enact solutions to reduce
      future risk.

      The problem that contributes to sewer backup in basements is primarily one of
      „extraneous flows‟, also known as „inflow & infiltration‟. Extraneous flow is otherwise
      clean water (usually from storm run-off, groundwater or watermain breaks) that enters the
      sanitary sewer system and causes overloading during periods of heavy rain, ground-thaw
      and snowmelt. Sources of extraneous flow include leaks in the sewer mains and sewer
      laterals from groundwater, surface water sources inflowing into the sanitary sewer, cross-
      connections to the storm sewer system, adjacent watermain breaks, as well as illegal
      connections to the sanitary sewer including foundation drains, sump pumps and



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      downspouts. Sources of extraneous flow generally include both public and private
      infrastructure and sources of water.

Perhaps the biggest consideration for aggressively pursuing disconnection of private-sources of
extraneous flow is the following: Not only do one’s own illegal connections put one’s own
home at greater risk of flooding, but those connections are contributing to flooding of
neighbour’s homes, or homes of individuals who are much further downstream, or
upstream for that matter, even if those other individuals are compliant with their own
connections.

      Addressing extraneous flows requires continued works on the public infrastructure, but
      also pointed efforts on private-property. Options for addressing private-property
      sources include;
          o By-Law enforcement,
          o Financial assistance programs,
          o Public ownership and/or,
          o Total capture of extraneous flows in the system via system design.

      Lack of Public education materials and formal data collection were identified as
      areas that would benefit from increased resources. Content for communication to the
      public is continuing to be developed and some basic preliminary information has already
      been uploaded to the Utilities Kingston website. The City‟s Communication‟s group has a
      draft plan in place but is contingent upon final content and available budget. A
      Basement Flood Reporting Tool to assist residents in reporting their basement flood
      events has already been placed on the Utilities Kingston website. We are also continuing
      our efforts to access information on flooding reports within the City from the Insurance
      Industry that is “public” in nature and that would assist the City in defining the scope and
      magnitude of areas impacted by sanitary sewer backups.

Background on Sewer Design
This section offers a brief background on servicing in the City of Kingston. It discusses the three
types of sewers found in the City today, plus 3 general categories of servicing, based on what
types of sewers are there, plus the nature of the connections to these sewers.




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The three sewer types are as follows:

      Storm Sewers. Storm drainage is comprised of 2 components; i) the minor system (the
      storm sewers in the ground) and ii) the major system (the overland flow pathways).
        i.)   The minor storm drainage system represents the storm sewers under the ground.
              They are traditionally designed for a 2- to 5-year storm event. For events less
              than this threshold, by design, all flows should be adequately captured by catch
              basins and other inlets and flows will be entirely conveyed beneath the ground.
              For events greater than this, the inlet capacity of catch basins and flow capacity of
              pipes is exceeded and drainage then relies on flow paths provided by the major
              system. This design practice is typical across North America and considered best
              practice to provide a reasonable level of service. Note that in some isolated area
              of the City, the minor system is comprised of road-side ditches, not underground
              pipe.
       ii.)   The major storm drainage system represents the conveyance abilities of the road
              network and surface drainage paths such as ditches, swales and constructed
              watercourses. They are traditionally designed for up to a 100- year event. These
              systems rely on flow containment in the roads where curb & gutter exists, to a
              point where they are able to discharge to another suitable overland flow path
              towards a receiving water body. These systems are often less efficient, and less
              able to be maintained due to private property works, lot regrading and
              redevelopment as well as vegetation growth. The further away from a water body,
              the more likely it is that the major system has flow impediments.

      Connections to the storm sewer generally include catch basins that enable road surface
      drainage and any impervious connected surfaces. In some areas, storm sewer laterals
      are constructed and allow for foundation drainage, sump pump flows and downspouts.

      Sanitary Sewers. Sanitary sewage collection is based on a single pipe network and
      does not have a redundant flow path similar to the storm drainage system. Sanitary
      sewers are sized based on a calculation of design sewage flow rates (usually very
      conservative, using 350-450 Litres/capita/day), peaking factors and a moderate
      allowance for extraneous flows.

      Connections to the sanitary system are restricted to service laterals originating from
      sewage producing buildings, mainly homes, apartments and businesses. However,




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      regulations and building codes pertaining to the legality of certain connections have
      evolved over time. In most areas of the City, no storm laterals are present, and therefore
      it is suspected that foundation drainage, sump pumps flows and downspouts may be
      connected to the sanitary system, resulting in considerable input of extraneous flows via
      connections that are today considered to be illegal, as per By-Law No. 2008-192. This
      was likely a common practice until the 1970‟s when new building code changes came
      into effect.

      Combined Sewers. Combined sewers are not constructed any more. However, these
      are some of the oldest sewers in our system today and the design process for sizing
      them has likely evolved over time. If a combined sewer were to be designed today, it
      would likely be constructed with a „5-year‟ storm design, plus allowances for sewage
      flows, peaking factors, and extraneous flows. Bypass points are critical in combined
      sewer systems, because on average, every 5 years, they will flood and have the potential
      to cause basement flooding. Bypasses are built into the collection system to protect
      homes. Given that bypasses are undesirable, as are basement backups, combined
      sewers are no longer constructed, based on regulations (MOE) and best practice. It
      should be noted that areas with combined sewers are at greatest risk of basement
      backups due to the fact their connections are to a sewer feature that is intended to
      surcharge, say, once every 5 years on average, but this risk is offset by the presence of
      bypass points that are intended to protect basements from flooding. This differs from
      sanitary sewers which generally do not have bypass points built into them. .

It should be noted that the Ministry of the Environment, in cooperation with other Ministries, has
prepared a document entitled “Ontario‟s Adaptation Strategy & Action Plan” (2011), which looks
to the potential impacts of climate change and mitigative measures that may be appropriate. A
number of action items pertain to wastewater and stormwater infrastructure and are suggestive
of upcoming changes to design standards.

Overall storm and sanitary servicing in the City is one of three primary categories, employing the
3 types of sewers discussed above:

      Overall servicing by „combined sewers’. One pipe in the ground to handle both storm
      runoff and sanitary sewage. These offer the greatest risk of flooding, except that this risk
      is largely offset by the presence of bypasses (over flows or combined sewer overflows-
      CSO‟s) in the system for protection. These systems are no longer constructed, and the
      Joint Reconstruction Program as part of the Multi-Year Plan in the City is pursuing




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       aggressive replacement of combined sewer systems. This is in alignment with best
       practice, and with the Council-approved recommendations of the Sewage Infrastructure
       Master Plan (2010) and generally deemed preferable by the Ministry of the Environment
       (MOE).

       Overall servicing by „partially separated’ sewers. Two pipes in the ground, one for
       storm runoff, one for sanitary sewage, yet remnant connections to the sanitary sewer
       may include some foundation drains, sump pumps and downspouts. These areas are
       also at risk of flooding due to the fact that the sanitary sewers that are designed for
       sanitary waste may also be receiving illegal extraneous flows from private property.
       Given that they do not receive surface drainage from roads, the risk level is probably
       somewhat less than that of combined sewer systems, except for the fact that there are no
       bypasses inherent in their design for basement flooding protection. Creation of new
       bypass points is prohibited by the MOE.

       Overall servicing by „fully separated‟ systems. Two pipes in the ground, one for storm
       runoff, one for sanitary sewage, with all storm-runoff/groundwater sources intentionally
       discharged to the storm system via the surface or a storm lateral per best practice. This
       servicing is believed to present the least risk for basement sewage backups but requires
       a commensurate level of storm-water servicing to ensure satisfactory drainage of surface
       water.

Figure 3 illustrates these types of systems in the context of drainage from a single home.

Figure 4 illustrates the servicing within the City of Kingston. The spatial extent of partially-
separated and fully-separated systems is unknown, but the map does show the remaining
combined sewer service area. The remainder of the urban portion of the City of Kingston is
generally serviced by separated systems, either partially- or fully-separated.




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FIGURE 3. SERVICING CONFIGURATIONS IN THE CITY OF KINGSTON.

            Layout                     Details
Combined                                  All flows, sanitary and        drainage
System                                    discharge to a single pipe.
                                           No longer constructed.
                                           Often partially protected by presence
                                           of bypasses to the environment or
                                           other adjacent storm sewers
                                           Risk level: MODERATE




Partially                                  Road drainage captured by storm
Separated                                  sewer
                                           All sanitary drainage plus private-side
                                           storm/ground drainage to sanitary
                                           No storm laterals
                                           Risk level: MODERATE




Fully                                      Road drainage plus private-side
Separated                                  drainage captured by storm sewer
                                           Only sanitary drainage to sanitary
                                           sewer
                                           Storm laterals, or sump pumps to
                                           surface
                                           Risk level: LOW




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     FIGURE 4. LOCATION OF COMBINED SEWERS IN THE CITY OF KINGSTON (REMAINDER IS SEPARATED)
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Mechanisms of Basement Flooding
The underlying cause of sewage backup was discussed in preceding sections of this report.
This section focuses on the mechanisms by which a sewer backup may occur and illustrates
them with diagrams. Please note that this section does not discuss pure storm-water or
groundwater flooding issues which generally result from poor or insufficient site drainage or
inadequate home maintenance, i.e. seepage through cracks, or sump pumps unable to keep up
with water in the sump. These are usually attributable to private-side drainage issues, not public
infrastructure.

Figure 5 illustrates a typical home in Kingston and details its internal plumbing and external
connections to the sanitary sewer system in profile. Note that a storm lateral, as is shown on
the diagram, does not exist in most homes in the City of Kingston. The presence of storm
laterals is based in part on building practices utilized in the various areas in the City of Kingston.
For example, in the former Pittsburgh Township, most homes were constructed with storm
laterals. Coincidentally, generally the eastern part of Kingston has consistently demonstrated
the least reported basement flooding events.

In general, the primary conditions that may induce a sewage backup are as follows:
       Elevated wastewater level in the sanitary sewer will cause, by gravity, flow towards the
       home via its connections.
       Impeded flow in the sewer lateral, via lack of maintenance or blockage, which might
       reduce the ability of the lateral to service the home. This is more critical when illegal
       connections exist, causing flow contributions from downspouts, sump pumps and/or
       foundation drainage which increases the amount of flow the lateral needs to convey.
       Completely blocked laterals by structural failure or failed backflow prevention through
       improper installation or lack of maintenance.

These scenarios are illustrated in Figure 6. As a result of these scenarios, wastewater (as
defined loosely as any water, sewage or clean-water that has entered the sanitary sewer or
sanitary plumbing of a home) will push its way out of the lowest exit points. These points
usually include floor drains, sumps (if foundations are connected to the sump and sanitary
system), laundry facilities, shower stalls and bath tubs, as well as toilets and sinks. In general,
any fixture or opening that is below the level of wastewater in the sewer main is at risk of
backing up. In addition, when foundation drainage is connected, an additional potential route of
entry is provided and wastewater is then able to foul the weeping tile system.




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There are two issues to consider in the interests of a reduction in flood risk:
   1. What can the City, Utilities Kingston, and its residents do to reduce extraneous flows, as
      a true source-control means of addressing the source of the problem?
   2. How does a homeowner protect themselves from a basement flooding, especially if they
      don‟t even know they are at risk?

These are discussed in the following sections of this report.




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 FIGURE 5. PROFILE OF TYPICAL HOME AND ITS CONNECTIONS TO SEWERS (SOURCE: HANDBOOK FOR REDUCING BASEMENT FLOODING, ICLR 2009).

     This diagram shows a home that is at risk of basement flooding from infiltration,       Sewer laterals have not been maintained, are cracked & have loose joints X/O
     overland flow and sewer backup. In this diagram:                                        Sewer mains may be leaky and subject to extraneous flows O
        The cracks in the foundation wall and basement are unsealed X
                                                                                             The storm sewer lateral has not been severed and is prone to exfiltration X
        Downspouts are connected to the sewer system or are discharging too close            The backfill area beside the foundation wall is uncapped X
        to the foundation X
                                                                                             The sewer cleanout is uncapped and unsealed X
        The yard is improperly graded and sloped toward the home X
                                                                                             There is no window well cover in place X
        The weeping tiles are connected to the sanitary sewer laterals X/O
        The weeping tiles have not been maintained and are damaged X
                                                                                         Responsibility KEY:    Homeowner - X           City/UK - O
        There is no backwater valve in place X
21
 FIGURE 5. PROFILE OF HOME INDICATING SURCHARGE CONDITIONS. (SOURCE: HANDBOOK FOR REDUCING BASEMENT FLOODING, ICLR 2009)

     This diagram shows how sewer backup can enter a home. In this diagram:          In this instance, the municipal storm sewer is also surcharging, and forcing
         The sanitary sewer is surcharging due to extraneous flows getting in, and   storm sewage into the homes storm sewer lateral (if it exists). High
         therefore pushing sewage back into the home through the lateral             pressure storm sewage is exfiltrating from the storm lateral and entering the
                                                                                     sanitary sewer lateral, thereby increasing the amount of sewage that enters
         Sewage is entering the basement through plumbing fixtures, including the    the basement
         floor drain and the unsealed sewer cleanout
                                                                                     The home‟s sanitary sewer lateral is also in disrepair, and water is entering
         Because the weeping tiles are connected to the sanitary sewer, sewage has   through cracks and loose joints
         been forced into the weeping tiles and is infiltrating into the basement
         through cracks in the basement walls
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Review of Building Code and Building Practice
Some forms of home construction, and in particular with respect to the drainage system
configuration, put certain homes at higher risk for basement flooding. Code and construction
practice have evolved over time, and while the building code governs some aspects of
construction, whether or not foundation drains are connected to a sanitary or storm lateral, or to
a sump system is almost independent of code.

With respect to sanitary drainage, Table 2 lists pertinent code considerations.

TABLE 2. CODE CONSIDERATIONS FOR NEW HOME DRAINAGE

 Timeframe       Code
 <1967           All plumbing in and around the house, including weepers, downspouts and all
                 sanitary fixtures could be connected into an internal combined system.
 1968-1992       Sanitary and storm drainage was required to be separate, but could then join
                 together underneath the foundation and discharge via a single „sanitary‟
                 lateral.
 1992-1995       Similar to that above, but code stipulated the separate pipes should be
                 connected on the exterior of the building.
 1995 -          Separated sanitary and storm laterals required to the property line.
 Today           No storm or groundwater drainage is permitted to be discharged to sanitary
                 sewers.

In general, any practice that combines storm drainage and foundation drainage into the sanitary
lateral not only contributes extraneous flows to the system, but generally places that home, or
adjacent homes, at an increased risk of flooding. Discussions with the Building Department
have led to the general understanding that:

      Prior to ~1970±, most connections were made as combined connections.
      After ~1970±, most connections were made as separated systems with
      storm/groundwater sources directed either to an internal sump pump, to an external
      storm stub in a common sanitary lateral trench, or to a storm lateral.

In essence then, anecdotally, it would appear that homes built prior to ~1970± would be at
greater risk of basement flooding by sewer backup due to the occurrence of converging of
storm/groundwater drainage to a potentially surcharged system.

Figure 7 illustrates the distribution of home age within the sewer serviced boundary of the City of
Kingston and illustrates the clustered flooding areas as per Figure 2.




                                               22
23
     FIGURE 6. HOME AGE DISTRIBUTION ACROSS THE CITY OF KINGSTON URBAN AREA.
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Figure 7 compares the age distribution of homes that reported flooding in July versus the
statistical distribution of home age within the City of Kingston urban area. Note that there
appears to be a distinct increase in flood reports from homes that are 40-70 years old
(constructed between 1940 and 1970).

  25%

  20%

  15%

  10%

   5%

   0%
        0              50                100               150              200

              Flooded Home Age Distribution         Home Age Distribution

FIGURE 7. AGE DISTRIBUTION OF FLOODED HOMES AND CITY-WIDE HOMES.

More research is required to determine if this is relevant, to validate anecdotal information to
determine if indeed there were specific construction practices pre-1970 that contribute to further
risk, or if the distribution is statistically irrelevant. It is possible this is simply caused by the
distribution of rainfall that fell, which is rarely uniform over large areas.

Addressing Extraneous Flows
Extraneous flows, as the underlying cause of sewer backups, is a nation-wide problem.
Extraneous flows exist everywhere, and the City of Kingston is among a long list of other
municipalities examining means to reduce it.

Utilities Kingston‟s efforts in extraneous flow reduction currently include:

        Flow Monitoring. A monitoring program has been in place for some time to document
        flows in sanitary sewers within the City. This data is analysed for the purposes of trying
        to identify the worst problem areas. In terms of monitoring data, these are the areas that
        show the biggest storm event response, and the greatest apparent amount of dry-
        weather infiltration. Flow monitoring has previously been used, and will be used more in
        the future to direct focused extraneous flow reduction efforts.



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    Sanitary Sewer Rehabilitation. Based on council direction on flooding experience in
    the North End Trunk Sewer service area in 2006, Utilities Kingston has undertaken 4
    years of extraneous flow reduction efforts on sewer mains in the service area, to a total
    value of approximately $5,000,000 over 4 years, including the latest phase for
    $2,500,000 which was cost-shared based on an ISF grant. A preliminary analysis of flow
    monitoring data has illustrated some reductions in dry-weather and wet-weather flows.
    This program requires more focused efforts based on additional flow monitoring and
    more spatially focused efforts on pipe segments as determined by flow monitoring data.
    This program is currently being reviewed and restructured. The former program has
    produced a considerable area, roughly ¼ of the central part of the City, with sewer pipe in
    structurally sound condition.

    Sanitary Sewer Cleaning & CCTV Inspection. Utilities Engineering conducts annual
    contracts for sewer cleaning and CCTV inspection. These inspections lead to
    maintenance of the sewers where warranted. The quantity of CCTV has recently been
    increased to strive for full City-wide coverage on a 10-20 year cycle, or more frequent for
    larger trunk sewers or features of the system with inherent higher risk of failure. CCTV
    allows for identification of areas subject to severe dry-weather extraneous flows and has
    been instrumental in identifying contributing watermain breaks.

    Combined Sewer Replacement. Utilities Kingston is aggressively integrating its sewer
    separation objectives within the Multi-Year Reconstruction Plan, which received approval
    from City Council in January 2011. The quantity of sewer separation in the current 4-year
    program represents separation of roughly 13.5% of the total remaining combined sewer
    area. At this rate, the City may achieve sewer separation in roughly 30 years. Of note
    within the current 4-year Capital Program is a substantial undertaking within the George
    St catchment, which extends northwards into the Queens Student Area, scheduled to
    commence in 2012.

    Tracking of Flood Reports. Utilities Kingston has been maintaining a database of flood
    reports to assist in determining where problem areas exist. Improvements to the tracking
    system have been made. For the March 5/6th event, a mail-out survey was created which
    received roughly 25-30% response. Since the July 29th event, a Basement Flood
    Reporting Tool was created on the Utilities Kingston website. Note that any further public
    education materials developed will highlight this reporting tool to improve future
    effectiveness of reporting.




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Additional areas that the City of Kingston and Utilities Kingston should consider for the reduction
of extraneous flows and reduction of sewage backups include:

      Coordination of Policies for Flooding Prevention. To date, there is no formal „Storm
      Water Policy‟ or „Storm Water Master Plan‟ suitable for assisting in the separation of
      sewers that would work in parallel with the Sewer Master Plan. The Combined Sewer
      Critical Evaluation results (Stantec, 2006, adopted by Council in 2007) endorsed a
      scenario where some degree of storm sewer capture is required within the sanitary
      system. While the study found that this concept proved to be the best alternative
      environmentally as it affects the receiving water bodies (lower pollutant loadings), it is a
      compromise for the sewer utility because it reduces the available capacity in the sanitary
      sewage collection system to convey sewage and extraneous flows during wet-weather or
      snowmelt events.

      During sewer separation, a parallel storm water policy would enable clear guidance on
      how to enact full separation of catchments, rather than partial separation, as it would
      address the applicability of storm laterals, as well as addressing treatment for storm
      water prior to discharge to the environment.

      Engaged the Private-Side Challenges. Many of the contributing extraneous flow
      sources originate on private property and this presents some social and legal challenges.
      A formal policy on how to address this is required, and may take some form of By-Law
      revision, By-Law enforcement, and financial assistance programs:

          o Enforcement of By-Law. Upon City Council‟s approval of the Sewer Use By-Law
            No. 2008-192 provisions around the illegal discharge of material to the sanitary
            sewer system were improved and continued with the new By-Law. The Sewer
            Use By-Law is very clear in its prohibition of extraneous water/flows to the
            collection system. Consequently under Sections 3.8 to 3.11 the connection of roof
            leaders/down spouts, sump pumps, and weeping tiles to the sanitary system are
            prohibited and subject to prosecution under the By-Law. Upon adoption of the
            Sewer Use By-Law, enforcement of these provisions has been on a complaint
            basis only. The Palace Road Pilot Study on Extraneous Flows demonstrated that
            only for items of small expense were more than a small fraction of participants
            willing to voluntarily comply and it was only when active enforcement of the By-
            Law within the Study area took place, was participation in the program increased.




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          It is staff‟s position that a critical component to addressing the extraneous flow
          problem as it relates to property flooding is a more aggressive and proactive By-
          Law enforcement program targeted at all areas of the sewer collection systems,
          but in particular at contributing areas that experienced flooding and those area
          “upstream” of noted problem areas.

       o Offer of Financial Assistance Programs. Table 3 describes various levels of
         financial assistance programs in some other municipalities within Ontario. It is
         clear that a number of municipalities have chosen to offer financial assistance to
         homeowners for private-property works deemed appropriate for reducing
         extraneous flows.




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REPORT TO ENVIRONMENT, INFRASTRUCTURE AND                                                                                                                       Report No.: EITP-12-003
TRANSPORTATION POLICIES COMMITTEE

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      TABLE 3. FINANCIAL ASSISTANCE PROGRAMS IN ONTARIO MUNICIPALITIES
                                   Components



                                                                  Storm Lateral
                                    Downspout


                                                       Backflow
                         Lateral


                                                Sump
          Location                                                                                             Overview                                             Funding Details



      City of Ottawa                                                             City of Ottawa has a ‘Protective Plumbing Program ’ that provides      Up to $2,500 - $7,500 based on
                                                                                  compensation for homes installing backflow prevention devices.         criteria, including 50% and 100%
                                                                                  Eligibility and $ value is based on frequency of flooding as well as   coverage options, depending on
                                                                                  compliance with all bylaws & codes.                                    eligibility criteria.
      City of Ottawa                                                             City of Ottawa, effective April 4, 2011, has mandated the use of       Developer/home buyer.
                                                                                  backwater valves on sanitary lateral for new home construction.
      City of Toronto                                                            City of Toronto has just initiated (in 2011) a ‘Mandatory              None
                                                                                  Downspout Disconnection Program’ , funded by private home-
                                                                                  owners. Incentives only available for low-income home-owners.
      City of Toronto                                                           The City of Toronto administers a ‘Basement Flooding Protection        Value of 80% of eligible costs up to
                                                                                  Subsidy Program’, provides financial assistance to homeowners          $3,200 based on work completed.
                                                                                  for activities including backwater protection, sump pump               Use of qualified, City-licensed
                                                                                  installation and foundation connection severance and capping.          plumbers.

      City of Toronto                                                            The City of Toronto administers compensation for tree root           Up to $2,000.
                                                                                  blockage of private laterals by City-owned trees.
      City of Toronto                                                            The Toronto City Council mandated installation of backflow valves, N/A
                                                                                  on sanitary laterals where there is a below grade living area in the
                                                                                  City, for any applicant of plumbing permit related to sewer drain.

      City of Hamilton                                                           The City of Hamilton administers a ‘Sewer Lateral Management       N/A
                                                                                  Program’ , focused on maintenance of the public portion. Financial
                                                                                  assistance may be provided when full lateral replacement/rehab is
                                                                                  undertaken on private-side along with that on the public side.

      City of Hamilton                                                         The City of Hamilton has a ‘Protective Plumbing Program’ that      100% up to $2,000 plus financing of
                                                                                  provides financial assistance for homeowners for backwater valve additional $2,000 loan.
                                                                                  installation, sump & pump installation (with backflow valve), CCTV
                                                                                  inspection and downspout disconnection + permit(s).

      City of St.                   
                                   The City of St. Catharines completed a 'Mandatory Downspout                                                           None
      Catharines                   Connection' program that lasted about 10yrs, and is finished with
                                   over 99% compliance.
      City of St.                The City of St. Catharines ‘Flood Alleviation Program (FLAP) ’                                                        100% up to $3,000
      Catharines                   provides grants to homeowners who have documented recurring
                                   sanitary back-ups as a result of sewer surcharging.
      City of                   The City of Peterborough administers a ‘Sanitary Backflow                                                             100% coverage up to $800 each, or
      Peterborough                 Prevention Subsidy Program’ which includes backwater valves,                                                          100% up to $1,800 for both backflow
                                   installation of a sump pit and pump required to disconnect                                                            and sump.
                                   foundation drains and/or storm water leaders from existing
                                   connections to the building sanitary sewer.
      City of London            The City of London administers a ‘Basement Flooding Grant                                                             75% of costs to various maximums
                                   Program’ which includes backwater valves, foundation drain                                                            ($2650 foot drains, $575 backwater
                                   disconnection, backwater valve installation and storm laterals.                                                       valves, $3775 storm lateral)
      City of Sudbury            The City of Sudbury administers a ‘Preventative Plumbing Subsidy’                                                     50% of eligible costs to various max
                                   which includes backflow prevention and/or sump pump                                                                   ($1000 for backflow, $1250 for sump
                                   construction to disconnect foundation drains.                                                                         construction, $2250 for both).
      City of Windsor             City of Windsor provides a free 'Downspout Disconnection                                                              None
                                   Service'
      City of Windsor             City of Windsor subsidizes sewer lateral replacements by way of a                                                     Up to maximum grant of $1,668.
                                   'Private Sewer Replacement Program'
      City of Windsor            The City of Windsor administers a 'Basement Flooding Protection                                                       Up to 80% of eligible costs to various
                                   Subsidy Program' which includes backflow prevention and/or                                                            max ($1000 for backflow, $1250 for
                                   sump pump construction & disconnection of foundation drains.                                                          sump construction, $2250 for both).




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          Many municipalities of those listed, administer a program packaged as a
          „Preventative Plumbing Program‟, or similar, that has multiple components to it, for
          a two-pronged purpose;

                  i)    to allow a homeowner to better isolate their home from flood sources
                        and
                  ii)   to reduce extraneous flows to the sanitary sewer system.

          Most programs offer anywhere from $1,000-$5,000, expressed as a percentage of
          the expenditure (typically 50-100%) of total eligible costs to the home owner for
          works on the private-side that reduce the risk of flooding to the owner while also
          reducing extraneous flow sources connected to the sanitary sewage collection
          system. Most programs have elements for backflow prevention devices as well as
          foundation disconnection works (including sump installation). The majority of
          municipalities do little in the way of private-side laterals, likely due to the legalities
          and cost, aside from larger cities like Toronto and Ottawa that generally take
          responsibility for root intrusion by City-owned trees. Worthy of note is that some
          cities, like Toronto, St. Catharines, Windsor and Thunder Bay, have mandatory
          downspout disconnection programs (no incentives), or via the eligibility criteria in
          their preventative plumbing programs, require that a homeowner already has their
          downspouts and sumps (if present), disconnected from the sewer system (i.e. the
          homeowner is compliant with all current bylaws/codes to be eligible).

    Review of Design Standards. Based on the fact that the City of Kingston appears to be
    subject to an increase in events that result in a significant number of basement sewage
    backups, it is prudent to at least consider the need for a review of design standards.

       o Storm sewer design. Storm design uses „Intensity-Duration-Frequency‟ curves to
         define a design event, as briefly mentioned in the beginning of this report. In light
         of climate change, the current or future design event may no longer be well
         represented by the design event used to date. This would require an examination
         of rainfall data to assess if changes in climate have been detected over the past
         decade and whether or not there is sufficient data to justify an update to the design
         standards used, or inclusion of a reasonable amount of additional capacity to
         account for uncertainty. This is being developed by the Ministry of the
         Environment in its “Ontario Adaptation Strategy and Action Plan” (2011).




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       o Sanitary Sewer Design. In absence of action to address private-side sources of
         extraneous flow, any sewer separation projects are generally resulting in new
         „partially separated‟ sewer service areas, not „fully separated‟. In other words
         homes still may have sumps, roof leaders, weepers still connected to the sewer
         lateral. In absence of procedures to disconnect these sources during
         reconstruction, an increased sizing of sanitary sewers to accommodate the
         problem may be justified. This, however, is a form of accommodating the problem
         (an illegal one) rather than fixing it. The preferred approach should be to eliminate
         those sources of extraneous flows.

    Sewer lateral Inspection & Rehabilitation. The condition of sewer laterals can also be
    a contributing factor to extraneous flows. The Sewer Use By-Law under Section 3.2
    provides authority to enforce the repair and maintenance of a sewer lateral on private
    property. While extraneous flows from laterals (public and private) is likely to occur and
    contribute to the problem, it is believed that due to risk and cost, at this time, the cost-
    benefit does not support developing a program to assist in sewer lateral repair work. A
    run-to-failure approach is deemed acceptable for these features. However, a lateral
    repair enforcement program does need to be in place for when deficiencies are identified
    through sewer main CCTV work. Formalizing a cost-sharing program with homeowners
    for repairs to the entire lateral (public and private) may be worthwhile, but this requires
    further research and development.




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How to Protect a Home from Flooding
Information on how a homeowner can protect themselves against flooding is readily available on
the internet, yet Utilities Kingston and the City of Kingston do not have their own information
packages on this topic. This has been identified as a need and is currently being developed in
conjunction with other departments including the Building Department, City Engineering and
Communications. Outreach will be a planned component of education material development.
Information from other Cities running similar assistance programs noted the importance of
communication and education as one of the factors contributing to successful programs.
For information, the graphic provided in Figure 9 illustrates a typical home in profile and several
measures homeowners can take to protect themselves against flooding. Ultimately, the best
protection against flooding relies on isolation from municipal systems. This is generally
achieved by:
      Foundation drainage and downspouts disconnected from the sanitary system and
      discharging to the lawn.
      Backflow prevention on the sanitary lateral.
      Either no storm connection at all or backflow prevention on the storm lateral.
      Maintenance of lateral(s) and backflow prevention devices and knowledge on how they
      operate and their limitations.

Several outstanding resources are as follows:
      Handbook for Reducing Basement Flooding. (ICLR, 2009)
      http://www.iclr.org/images/Basement_Flood_Handbook_-_ICLR_-_2009.pdf
      Practical Measures for the Prevention of Basement Flooding Due to Municipal Sewer
      Surcharge (CMHC, Research Highlight, January 2004). https://www03.cmhc-
      schl.gc.ca/catalog/productDetail.cfm?cat=42&itm=5&lang=en&fr=1317396801037
      Avoiding Basement Flooding (Canada Mortgage & Housing Corporation, Website, 2011)
      http://www.cmhc-schl.gc.ca/en/co/maho/gemare/gemare_002.cfm




                                                31
32
     FIGURE 8. FLOOD-RISK REDUCTION OPTIONS IN TYPICAL HOME (SOURCE: HANDBOOK FOR REDUCING BASEMENT FLOODING, ICLR 2009)

     This diagram shows how retrofits and maintenance can reduce flood risk.    To reduce infiltration flooding risk:
                                                                                    Cracks in the foundation walls and basement floor have been sealed
     To reduce overland flooding risk, infiltration and sewer backup:               Weeping tiles have been repaired and are in good working order
         A properly graded yard directs water away from the home                To reduce sewer backup risk:
         The backfill zone has been capped with an impermeable soil                 A normally-open backwater valve has been installed in the sanitary lateral
         The downspouts have been disconnected from the sewer system                Weeping tiles are drained into a sump pit, and water is pumped from the
         Extensions on the downspouts and sump-pump discharge keep water away       sump to the lot‟s lawn using a sump pump (or two)
         from the home                                                              Cracks and loose joints in the sanitary sewer lateral have been repaired
         A cover has been placed over the window well                               The storm sewer lateral has been severed
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Challenges
There are clearly a number of challenges with the development of any policy and/or programs
required to address sewage backups. A discussion of the challenges is presented below.

   1. Decision-making: Source Control versus Conveyance & End-of-Pipe Control
      The problem is excessive extraneous flows in the sanitary sewer system. Solutions
      range from providing a true „source control‟ approach versus a „conveyance & end-of-
      pipe control‟ approach. A „source control‟ approach looks at finding the sources of the
      excess water and then defines appropriate methods to eliminate the water at the source.
      The alternative, a „conveyance & end-of-pipe control‟ approach considers source control
      very difficult to achieve and thus looks to provide solutions to accommodate the excess
      flows within collection system capacity and ultimately the wastewater treatment capacity
      at end-of-pipe. Table 4 provides an overview of the elements to each approach.

      Utilities Kingston has a firm preference for pursuing activities that reduce extraneous
      flows at the source. This approach is consistent with the methodology now employed by
      the City to reduce combined sewer overflows.

   2. Target audiences and how to achieve buy-in and uptake.

      There are challenges with developing programs to achieve buy-in and uptake by
      homeowners based on a number of factors including:
         Perception of need. If a homeowner has experienced a flood or multiple floods, they
         are aware of the costs & hardships involved and are likely to see a positive cost-
         benefit to undertaking „preventative plumbing‟ and extraneous flow reduction works on
         their home. A homeowner, who has not flooded or is unaware that their illegal
         connections are causing flooding to their neighbours or other homeowners, is likely
         much less willing to invest in works to reduce their extraneous flow inputs to the
         system.
         Finances. A homeowner in a more favourable financial state is much more likely to
         undertake any work, or participate in any programs than a homeowner in a less
         favourable financial state. As such, there may be special provisions for low-income
         households.




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       Disturbance. Several of the measures required to reduce extraneous flows from
       private sources may cause disturbance to landscaping and internal home finishing
       (i.e. weeping tile correction). Depending on the works required, it is potentially a
       significant disturbance.

  3. Cause and Effect

    Removal of extraneous flow sources to the sanitary system require redirection of these
    flows to another location or conveyance mechanism. By diverting downspouts and sump
    pumps to lawns, for example, the side-effect is that surface and ground-water flooding
    problems and risks may be exacerbated.




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Programs need to be carefully designed to take the above factors into consideration to
maximize their uptake and effectiveness.

TABLE 4. APPROACH-STYLES TO ADDRESSING EXTRANEOUS FLOWS

Approach           Elements                  Pros                      Cons
Source             Private-Side Source        Funding split between     Heavy on the private-side issues
Control            Reduction                  private/public can be     & interactions
                       Downspouts             carefully determined.     May cause an increase in
Reduce                 Foundations/Sumps      Addressing the            surface flooding issues
extraneous                                    problem at the source.
                       Laterals                                         Complex & will require a
                                                                                                            
flows at the
source and         Public-Side Source         No need to provide        comprehensive approach
prevent it from    Reduction                  conveyance or end-of-
entering               Sewer Mains            pipe improvements
sanitary system                               since capacity already
                       Cross-connections      exists.
                       Laterals
                                              Reduction in bypasses
                       Sewer Separation
Conveyance         Public-Side Collection     Involves little to no     Replacement of a considerable
Control            System Upgrades            private-side              % of City‟s sewer infrastructure.
                      Identification of       issues/interactions       Will take decades to accomplish
Accommodate           problem areas                                     as it would need to be
extraneous                                                              accommodated into City‟s Road
                      Build in extra
flows in the
                                                                                                            
                      capacity by                                       Reconstruction Programming.
sanitary sewer
                      replacing existing                                Infrastructure will be more
system by
providing more        Build-in temporary                                frequently underutilized.
flow capacity.        storage                                           Will be more expensive to
                      Upgrade capacity of                               construct and require more
                      downstream pump                                   resources to maintain.
                      stations to suit                                  Would also require end-of-pipe.
End-of-Pipe        Wastewater Treatment       Involves little to no     Treating considerable water that
Control            Plants                     private-side              does not require treatment.
                      Increase treatment      issues/interactions
Accommodate                                                             Upgrades to WWTP are
                      capacity
extraneous                                                              expensive and most of
                      Increase bypass                                   equipment will be unused except
flows conveyed
                      capacity
                                                                                                            
to end-of-pipe                                                          for during storm events.
by providing       Sewer Overflows
                                                                        More CSO, move out of
adequate              More CSO storage
capacity of flow                                                        compliance with MOE F-5-5.
                      tanks & bypass
and treatment.        locations.                                        End-of-Pipe controls along are
                                                                        not able to reduce risk of
                      Treatment of CSO
                                                                        basement flooding without
                      required
                                                                        increased conveyance.




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Recommendations
The City of Kingston has been subjected to two major events to date in the 2011 Calendar Year,
and one roughly every 2-4 years prior including 2009, 2006, 2004 and 2003. There are no
assurances that additional events will not occur within a short-time frame. If the general notions
of climate change hold true, in that our region should expect more frequent severe weather
events, the City, in anticipation, may wish to undertake mitigative measures to reduce the risk of
basement flooding to residents of the City. The City and Utilities Kingston may wish to consider
adopting guiding principles and actions identified in Ontario‟s Adaptation Strategy and Action
Plan (MOE, 2011).

Province-wide, it appears to be common practice for municipalities to undertake programs to
assist the homeowner in disconnection of extraneous flow sources on the private-side in light of
the greater good it achieves for the community/neighbourhood as a whole.

It is important to stress that the programs listed below are considered beneficial in reducing the
risk of flooding by reducing the amount of extraneous flow directed to the sanitary sewer, but will
not, and do not strive to eliminate the problem, nor are they a guarantee against further
basement flooding. Basements, generally being below the ground surface, are features that will
always have some inherent flood risk no matter what programs are utilized.

The following list recommends programs, processes and policies for approval by Council.
These are all targeted at reducing the extraneous flow problem via true source control measures
of extraneous flow reduction as a best practice and providing additional flood protection to
homeowners.

1. That the City implement a „Private-Side Extraneous Flow Reduction Program’ consisting
   of three elements. This program would require new funding to administer and to provide
   financial assistance to property Owner:

     i.)   Preventative Plumbing Program
           This is primarily a financial assistance package for homeowners who have
           experienced basement flooding. There is precedent for such programs in other
           municipalities in Ontario (as demonstrated in Table 3).
              This program would include financial assistance to homeowners for sump
              construction and installation where none exists today, foundation drainage
              connection capping, and backwater valve installation. In short, mechanisms to




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             better isolate the home from flood sources. These are generally the higher cost
             items where finances would otherwise serve as a disincentive to undertaking this
             work.
             Eligibility criteria will need to be carefully defined, but in general terms, eligibility
             should be based on location (must be in sanitary sewer service area), the ability to
             provide documentation of flooding events, or be located within a neighbourhood
             with a history of flooding. Depending on success, uptake and demand for this
             program, there may be justification to extend eligibility to all Utilities Kingston
             sewer customers at a later date, but the initial focus should be on the areas which
             experienced problems
             In addition, eligibility would also be based on compliance with Bylaw No. 2008-192
             with respect to sump pump drainage (if it already exists) and downspouts.
             The program should provide a reasonable percentage, say 60-80%, of eligible
             costs up to predefined limits. This provides funding for the majority of the costs,
             but still relies on financial participation by homeowners to deter abuse of the
             program.
             The program would utilize an upset budget for 2012 and would be based on a first
             come, first serve basis.
             This program will require staff to develop the program criteria, manage
             applications, as well as pre- and post-inspections to verify works completed and
             expenditures claimed. This will represent a reallocation of staff to the program.
             This program will not be eligible to homeowners where storm and groundwater
             seepage and sump pump failure are the causes of flooding as these are due to
             maintenance issues entirely on the private-side. This program focuses on the
             reduction in flood risk from municipal infrastructure and in particular the sanitary
             system.


   ii.)   Downspout Disconnection Program

          The existing Sewer Use By-Law (No. 2008-192) requires downspouts to be
          disconnected from the sanitary lateral and therefore proactive enforcement of the By-
          Law is recommended.




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             Downspout disconnection is the least expensive and easiest first step to reduce
             wet-weather extraneous flows from a property. Given that By-Law No. 2008-192
             covers this item as an illegal connection (Section 3.11), enforcement of the By-
             Law will allow the City to work towards mandatory disconnection of as many
             downspouts as is feasible. Downspout disconnection is considered to be the most
             straightforward means of eliminating extraneous flow, partially since visual
             inspections can be done by inspectors without home-entry required.
             The development of exemption criteria and an exemption list should be utilized to
             support this program, as there will be circumstances where downspout
             disconnection is not technically feasible, or undesirable from a health and safety
             standpoint. One example of this would be a home in downtown Kingston where
             the only option would be to discharge downspouts to a sidewalk or towards a
             neighbour‟s property that is likely to create negative impacts.


  iii.)   Sump Pump Disconnection Program

          The existing Sewer Use By-Law (No. 2008-192) requires sump pumps to be
          disconnected from the sanitary lateral and therefore proactive enforcement of the By-
          Law is recommended.
                Similar to downspouts, sump pumps connected to the sanitary lateral are
                capable of delivering considerable extraneous flows. Enforcement of
                disconnection of sumps adds a layer of complexity above and beyond that of
                downspouts since it requires in-home inspections and home-owner interaction
                to complete. A similar exemption system would also be required as mentioned
                above.
                Mandatory disconnection of sump pumps is recommended, however as there
                is likely to be extra expenses associated with this program, it is recommended
                that some financial assistance to assist homeowners with this work be provided
                as an incentive to undertake the work, prior to undertaking legal action to
                enforce the By-Law.
                One approach that can be considered is a simple grant to support this program
                upon verification of complied work.




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2. That the City implement a Public-Side Extraneous Flow Reduction Program consisting of
   three elements. This program would reallocate some of the existing capital budget money
   previously approved in the 4 year capital budget. Two of the three elements, would be
   initiated in 2012, and one of which is for further research and consideration:

    i.)    Targeting, tracking down and eliminating direct inflow sources of extraneous flow on
           municipally owned infrastructure would become a new priority. This element of the
           program would focus on a rapid-response to sources of extraneous flows such as
           cross-connections and major defaults/breaks in the system. This activity would
           require the use of techniques that are more intrusive to the community than normally
           seen such as fog testing, dye testing and a number of mitigative techniques to redirect
           or plug inflow sources. This will be implemented in the short-term for a 2012 start.

    ii.)   Continuation of the general Extraneous Flow Reduction Program. This program
           will focus more-so on the non-direct sources and utilize techniques such as flow
           monitoring, sewer inspection during wet-weather and mitigative techniques such as
           joint testing & sealing, spot repairs and full length sewer lining. This can occur in the
           short-term, but progress through the City is generally slow at existing budget levels.

   iii.)   For future consideration, dealing with leaky public/private-side laterals should be
           explored. Sewer laterals may form as much as 40-50% of the entire length of the
           sewer system. While smaller in size, laterals have the potential to generate a
           significant amount of both wet- and dry-weather flow by way of leakage. Utilities
           Kingston shall research means to best approach this part of the problem and report
           back to council in the future.

3. That the City implement and endorse the following:

    i.)    That as part of the annual road reconstruction program involving the replacement of
           sanitary sewer mains an early communication/educational program regarding
           extraneous flow reduction be undertaken with affected property owners to alert
           owners that there will be an expectation/requirement on the part of residents to
           ensure that no illegal connections to the sanitary system are present at the completion
           of the project.




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    ii.)   That as part of the annual road reconstruction program involving the replacement of
           sanitary sewer mains that proactive By-Law enforcement to ensure that no illegal
           connections to the sanitary sewer system exist upon completion of the project be
           undertaken in conjunction with the communication/educational program.

   iii.)   That consideration for mandating the use of backflow prevention devices as part of
           the private-side system, on both the sanitary lateral and storm lateral (if they exist in
           the development) on all new residential development be reviewed by staff and that
           staff report back to Council regarding the feasibility and impact of such a change.
           There is precedent for this in a number of other municipalities including the City of
           Ottawa on new homes.

4. City of Kingston and Utilities Kingston to develop a comprehensive Public Education
   Package on basement flooding utilizing a number of media options for distribution and
   outreach. This development is underway. This information package shall include the
   following primary topics:

     i.)   What to do if you have a flooded basement

    ii.)   Causes of basement flooding

   iii.)   How to protect your home

   iv.)    What is the City/Utilities Kingston doing about the problem

    v.)    Assistance Programs

   vi.)    Glossary of terms

5. That in conjunction with the Private-Side Extraneous Flow Reduction Program‟ and the
   Comprehensive Public Education Package on Basement Flooding that a proactive By-Law
   enforcement program be undertaken to ensure that where ever possible extraneous flows
   are eliminated from the sanitary system in order to reduce the contribution of that source to
   basement flooding in the City.

6. That a review of existing policies and practices be completed to determine the effectiveness
   or shortcomings in reducing flooding of all kinds, and provide recommendations for new
   policies, guidelines and/or practices suitable for achieving flood reduction objectives.




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EXISTING POLICY/BY LAW:
Sewer Use By-Law 2008-192

NOTICE PROVISIONS: Not Applicable

ACCESSIBILITY CONSIDERATIONS: Not Applicable

FINANCIAL CONSIDERATIONS:

The Private-Side Extraneous Flow Reduction Program involves financial assistance to property
owners to mitigate sanitary back-ups on properties. As part of the 2012 Operating Budget,
Utilities Kingston has included a budget of $350,000 administer and fund the various programs
identified including the Preventative Plumbing Program and Sump Pump Disconnection
Program and Communication/Education Program.

CONTACTS:

Hal Linscott, Director of Legal Services                                613-546-4291 X1296
Terry Willing, Director of Building & Licensing                         613-546-4291 X3240
Mark Van Buren, Director of Engineering                                 613-546-4291 X3218
Paul MacLatchy, Director Environment and Sustainability Initiatives     613-546-4291 X1226

OTHER CITY OF KINGSTON STAFF CONSULTED: Not Applicable

EXHIBITS ATTACHED: Not Applicable




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