Loading...
HomeMy WebLinkAboutDTS-08-113 - Stormwater Management Audit - 5 Year Report CardREPORT Report To: Chair Christina Weylie and Members Development and Technical Services Committee Date of Meeting: August 11, 2008 Submitted By: K. Grant Murphy, Director, Engineering Services Prepared By: Diana Lupsa, Engineering Technologist Wards} Involved: All Date of Report: July 29, 2008 Report No.: DTS-08-113 Subject: Stormwater Management Audit - 5 Year Report Card RECOMMENDATION: That Council receive and endorse the attached Stormwater Management Audit - 5 Year Report Card Technical Summary (2002 to 2006} prepared by Totten Sims Hubicki Associates and further; That Council direct staff to review the Stormwater Management Redevelopment/lnfill Charge as part of the 2009 budget deliberations. BACKGROUND: In 2001, the City of Kitchener developed a Master Stormwater Management SWM) Policy that outlined the City's strategy for dealing with stormwater management related to development. This policy specified that the City would monitor its streams to establish the effectiveness of the policy on improving water quality, aquatic habitat and stream stability. The status of works completed as part of the policy, a review of the SWM Redevelopment/lnfill Charge (cash-in-lieu} along with the monitoring results are incorporated in yearly SWM Audit reports completed since 2002. Because it sometimes takes several years for trends in data to become apparent, a Five Year Report on the status of the policy effectiveness was also recommended. REPORT: As mandated by the Master Stormwater Management (SWM) Policy, in 2002 the City of Kitchener initiated a monitoring program to detail current status under both dry and wet conditions and to establish trends to determine how the implementation of the Master SWM Policy is acting to improve water quality and ecosystem health. The monitoring program included a moving set of 7 to 8 stations on streams within the City of Kitchener. At most locations samples were taken for water quality analysis and an assessment of aquatic ecological health was made with benthic invertebrate samples and fish surveys. In the summers of 2004 and 2005 the majority of the streams in the City of Kitchener were walked to identify physical characteristics including sites of local erosion. Further aerial photography was available from 2002 and 2006. During the 2001 stormwater Management Policy development, the drainage areas of all SWM facilities were identified and each facility was assessed for its quality and quantity control. As new facilities were added and existing facilities were retrofitted, the information was captured and included annually in the SWM Audit reports. Four sets of parameters have been used to evaluate the effectiveness of the SWM plan; each parameter says something about how the system is functioning and what potential there is for improvement. These parameters are chemical, biological, physical and overall stormwater management practices. Using the monitoring data collected between 2002 - 2006, the City's consultant rated each parameter using an "excellent/good/fair/marginal/poor" system that is specific to each indicator. The parameters have been assessed against generally accepted standards and guidelines, and methods that can be repeated at regular intervals have been used. Chemical The quality of the water in our streams and rivers is important to the health of both the aquatic ecosystems; the tax payers in the City of Kitchener and recipients of drinking water downstream. Clean water supports a diverse biotic community, recreational activities within parks and green spaces as well as contributing to overall human health within and downstream of the City. The quality of water in City of Kitchener streams was assessed using the results of the chemical and microbiological testing done on water samples collected as part of the audit program (dry and wet). The purpose of the water quality sampling and reporting is to determine how well the system is managing stormwater. A summary of the overall ratings for the dry and wet weather events is presented in the Table 1 below: Table 1. Overall Ratings- Chemical Parameter Chemical -Creeks Overall Rating Parameter Schneider Creek Henry Sturm Greenway Montgomery Creek Strasburg Creek Idlewood Creek Kolb Creek Dry Marginal Marginal Poor Good -Fair Good Marginal Wet Poor Poor Poor Marginal - Poor Poor Poor The results are showing that majority of the streams have reduced water quality, especially during wet weather events. Some streams are showing fairly good results (Idlewood and Strasburg) but even these have reduced ratings during storm events. 2 For streams that have multiple water quality sampling stations, there was some indication that of a decrease in water quality along the length of the stream. Many of the streams also have their confluences with major waterways in more densely populated and industrial areas near the centre of the City where quality control is more limited. It is obvious that in wet weather conditions water quality is degraded compared to dry weather samples. This indicates that stormwater management practices within the City require upgrading to manage wet weather flows and reduce the water quality degradation. Biological The type and diversity of aquatic life in our streams indicates the level of health of the aquatic ecosystems in the City of Kitchener. The invertebrate and fish populations also establish the time-averaged health of the stream as they respond to changes in water quality, temperature and the physical conditions in the streams. Aquatic invertebrates (larval stages of insects, aquatic worms and freshwater shrimp, for example) and fish were identified each summer at 7 rotating locations as part of the City-wide stormwater program. Indices of biological health have been established for each location based on the number of individuals and type of aquatic life found. The Table 2 summarizes the level of aquatic health as determined by biological indices for each creek. Table 2. Overall Ratings- Biological Parameter Biological -Creeks Overall Rating Parameter Schneider Henry Sturm Montgomery Strasburg Idlewood Kolb Creek Greenway Creek Creek Creek Creek Value Marginal Fair -Poor Marginal Fair - Good Fair -Poor Mar final The highest quality is seen in the Idlewood Creek with the lowest in the more developed areas of the City having the least amount of area treated by stormwater management facilities. Many of the lowest rated stations are located within or downstream of straightened or concrete lined channels. The City-wide stormwater management program will use these values to help prioritize new stormwater management projects and initiatives. Physical The physical condition of the City's streams can have a direct impact on habitat available for aquatic life, the water quality in the stream and the speed at which water gets transported downstream (affecting erosion and flooding). Vegetation along a stream bank riparian cover} prevents erosion, allows shading to decrease stream temperatures, provides a natural filter for water entering the stream, slows down water entering the stream and provides cover and direct habitat for aquatic life. Reductions in vegetation along the stream banks significantly increases temperatures in the stream and add to erosion along the stream banks. 3 In 2004 and 2005, a physical assessment of all the creeks was completed identifying the areas where stream bank erosion was occurring. In addition, aerial photography analysis identified the amount of heavy vegetation cover along each stream reach. Table 3 below summarizes the level of vegetative cover along each stream and the erosion. Table 3. Overall Ratings- Physical Parameter Physical -Creeks Overall Rating Parameter Schneider Henry Sturm Montgomery Strasburg Idlewood Kolb Creek Greenway Creek Creek Creek Creek Riparian Fair Poor Poor Good Excellent Excellent Cover Erosion Poor Excellent Excellent Excellent Good Excellent Areas Schneider Creek has a high number of erosion areas and many of the streams in the city have less than 50% vegetative cover. Environment Canada X2004} indicates that stream degradation occurs when riparian vegetation goes below 75 % along streams. Stormwater Management Although not a specific stream parameter, the type and form of the stormwater management facilities, including streams, channels and ponds is an important parameter to consider when determining the overall health of the watershed. The goal of stormwater management is to reduce the water quantity and quality impacts of development on downstream watercourses for the protection of aquatic ecosystems, human health and human property (minimizing flooding and erosion risks). Stormwater management in the form of ponds and oil and grit separators (OGS) are constructed to treat the water quality and limit the quantity of water entering receiving streams. The area draining into the ponds was identified along with the level of treatment (quality, quantity or both). Streams in the City have been identified as natural, straightened or concrete lined. The stream characteristics have an impact on the water quantity and quality, with straightened and concrete lined channels not dissipating the stream energy and increasing the potential for erosion. The Table 4 summarizes the City's ratings for stormwater management coverage (based on the percentage of drainage areas serviced by stormwater ponds, and OGSs) and the channel type ratings. Table 4.Overall Ratings- Stormwater Stormwater -Creeks Overall Rating Parameter Schneider Creek Henry Sturm Greenwa Montgomery Creek Strasburg Creek Idlewood Creek Kolb Creek Treated Area Qualit Poor Marginal Poor Fair Fair Marginal Channel Type Good Fair Marginal Excellent Excellent Good 4 Currently, most of the City's developed land area does not have its stormwater runoff treated by stormwater management quality controls and this is evident by the reduced water quality in many of its streams, especially during wet events. The stormwater management program has identified priorities for improving this situation by upgrading existing SWM facilities, building new SWM facilities and restoring deteriorated stream reaches. In June 2005, Council recommended the award of the Stormwater Utility Program and Funding Review to Totten Sims Hubicki which was to be conducted jointly with the City of Waterloo. The study was undertaken to identify the Cities' existing stormwater assets, review it's existing stormwater programs, identify a suggested level of service and finally, to identify, review and recommend a preferred funding mechanism. FINANCIAL IMPLICATIONS: Between 2002 and 2006, $922,000 in Stormwater Management Redevelopment/Infill Charges (cash-in-lieu) have been collected to improve stormwater quality in areas of the City where it is not feasible for developments to install SWM facilities, and are to be used to construct or retrofit SWM facilities. Funding received from the collection of the Stormwater Management Redevelopment/lnfill Charge has been used for the following projects: Thistledown Pond retrofit (2005) - $115,000.00 Voisin Greenway Rehabilitation (2005) - $50,000.00 One OGS unit (2006) - $52,000.00 The City of Kitchener is constrained to provide a sustainable approach to stormwater management and environmental protection. The City is currently not meeting Provincial and Federal regulations and guidelines with respect to stormwater management operations and maintenance is generally reactive with respect to capital projects/expenditures and other program elements. Further the Stormwater Management Redevelopment/lnfill Charge does not adequately fund the necessary upgrades to existing SWM facilities or construct new SWM facility installations. As such the City has been completing a Stormwater Management Program and Funding Review, which has been ongoing since 2005. The purpose of the study is to identify the deficiencies within the program, develop a suggested level of service with respect to stormwater management and recommend a preferred funding mechanism for the program. The program consists of four general components: operation and maintenance, environmental compliance, capital improvement projects and planning and management. To date, a suggested level of service has been identified that requires the City to move from $4.5M to approximately $9.OM annually. It is expected that this report would be coming forward to Council before the end of 2008. Some of the activities that the City is planning to complete include: Rehabilitation of older stormwater ponds to meet current standards Construction of new ponds to increase the coverage of stormwater treatment Installation of new oil and grit separators Ensure appropriate maintenance of stormwater facilities Installation of at source stormwater controls such as infiltration systems where appropriate The rehabilitation of impacted streams 5 Continued monitoring and reporting of stream health A continuation of the Yellow Fish Road program A public education program as part of the Stormwater Management Program and Funding Review Study Other environmental protection and enhancement projects COMMUNICATIONS: Throughout this process and the Stormwater Management Program and Funding Review Study, it was determined that the level of awareness and knowledge among the general public regarding the topic of stormwater management is quite low. A communications plan is being developed to increase the level of awareness regarding stormwater management throughout a public education program. Based on the 5 Year Report Card Technical Summary, a pamphlet in user friendly format was designed to present environmental information to the broader public. It provides an overview of the effectiveness of the City-wide stormwater management policy in terms of the physical, biological and chemical condition of the receiving streams within the City. As part of a broader communications plan the following means will be used for distribution of the summary report card: Report Card pamphlet will be made available at various city facilities including community centers, senior centres, pools and City Hall City's website At various local special events (ie Earth Day, Groundwater festival} Additionally, Your Kitchener and media releases will and have been used to share the information and the project team is working with its various member organizations to get the information out through their networks, agencies and events. CONCLUSION: The City is acting to improve the status of its streams and rivers through the City-wide Stormwater Management Program. It is committed to improving water quality, physical stability and aquatic ecosystem function to enhance the environment, human enjoyment of the City and health of its residents. The City-wide Stormwater Management Program is identifying and monitoring areas that require improved stromwater controls within the City and prioritising work that will most cost-effectively improve the functioning of receiving water bodies. Staff will continue to work with the Consultants and the Steering Committees to prepare the 2008 Annual Audit. At the beginning of 2011 a second 5-year report card will be prepared. K. Grant Murphy, P. Eng. Director, Engineering Services Diana Lupsa Engineering Technologist 6