Stormwater ManagementA Municipal Perspective
Water and Cities Breakout SessionCanadian Water Summit
June 14, 2011
John Nemeth, Manager of Water Resources Design, Construction and Water Resources Division
Environment and Infrastructure ServicesTown of Richmond Hill
Why are we here?
• Approximately 50% of homeowner claims are due to water damage
• Upgrading Canada’s infrastructure is estimated to cost 80-90 billion
• Municipalities are attempting to deal with water pricing, infrastructure, watershed planning and water treatment
Source: Infrastructure Canada
About Richmond Hill
Richmond Hill is nestled in the middle of the Greater Toronto Area, within the boundaries of York Region
Over half of Richmond Hill is located on the Oak Ridges Moraine, an important ecological feature of Southern Ontario
Richmond Hill SWM Collaborative• National Benchmarking Initiative
– 46 major municipalities across Canada (26 for SWM)– Program advisor to AECOM Vancouver (since 2002)
• Southern Ontario– Municipal Stormwater Discussion Group (Chair)
• 45 Municipalities across Southern Ontario• Quarterly meetings since 2006
• Lower Tier Municipality• Development Charge Bylaws • 325 Subdivision Agreements• 20 MESP’s
Introduction of Stormwater Management• The practice of applying Stormwater
Practices started in the 1980s
• State of the Art technology has been changed six times over the past 30 years
• A 10 Year Stormwater Management Capital Program was created to update the Town of Richmond Hill’s stormwater management facilities
Online Weir
Online Quantity
Quantity/Quality
Provincial Interest• Places to Grow Act, 2005• Provincial Policy Statement, 2005• Oak Ridges Moraine Act • Greenbelt Act, 2005 • Oak Ridges Moraine Conservation Act, 2001• Clean Water Act• Ontario Water Resources Act, 2007• Stormwater Management Planning and Design Manual, 2003
Water Opportunities Act– The act will help municipalities improve the efficiency of
municipal infrastructure and services by:• Identifying innovative, cost effective solutions to solve water
challenges • Optimizing systems and improving water conservation • Identifying opportunities to demonstrate and implement new
and emerging Ontario water technologies, services and practices.
Source: MOE, 2011
Provincial Interest
Showcasing Water Innovation Funding Program deadline to apply is June 24, 2011
Regional Watershed Planning Direction
• Regional municipalities are providing support and direction with regard to stormwater management planning and environmental protection– Region of York
• Official Plan • Road Department Project Management
– Region of Peel • Climate Mitigation and Adaptation Planning • Sustainability Plans • Green Development Standards
Watershed Protection
Using a watershed management approach in water resources will
allow for consideration of water balance, aquatic
species, vegetation, flooding and erosion
Integrating Stormwater Management into Municipal Programs
• Town of Richmond Hill– 10 Year Stormwater Management Capital Program
• City of Toronto – Wet Weather Flow Master Plan
• Town of Markham– Small Streams Study
• Stormwater Management Master Plans in various municipalities
Stormwater Management Facility Priority Rating System - Evaluation Criteria-SRW.06.09
VALUE*Flood Protection 25%Statutory and Regulatory Requirements 20%Risk Management / Health and Safety Issues 15%Operations and Maintenance Considerations 15%Cost Benefit Analysis 5%Erosion Control and Slope Stabilization 5%Spills Management 5%Environmental Issues 5%Community Concerns 5%
SWM Facility Priorities
*Denotes priority rating of each criteria
Major Rehabilitation
Ten Year SWM Capital Program
Current Capital Projects
Pioneer Park: Complete
Don Head West: Construction 2011
Rumble: Design 2011
Harding Park East: Feasibility 2011
Example of Rehabilitation Project: Pioneer Park SWMF
• Pioneer Park SWMF rehabilitation was the first major stormwater capital project by the Town
History of Pioneer Park SWM • Originally built in 1980’s.• Dry, on-line stormwater quantity control facility for 26 ha of residential
development. • Original control structure was an online dam, with inappropriate
volume control being provided.• Over time, failure of the dam outlet structure (blockages) created a
backwater condition.• Backwater condition resulted in the creation of wetland conditions
including the collection of sediment and increased water temperature.
• Pioneer Park provides a SWM Master Plan for the Watershed– Increase in serviced tributary area
from 26 Ha to 740 Ha.
SWMF Rehab Using a Watershed Perspective
• Traditional stormwater ponds were designed to accommodate storm drainage in the immediate area and did not account for various factors– Impacts of fisheries– Cumulative drainage of the watershed– Climate change
Designing the New Pioneer Park SWMF Introduction of Hydraulic Performance Optimization Introduction of Operations and Maintenance efficiency Comprehensive SWM master planning for a 740 ha area of existing
community Flood protection up to 100-year return storm was incorporated Potential impacts to climate change were considered in the design
Off-line wet pond quantity, quality control, erosion protection, temperature mitigation and fisheries habitat
creation Re-creation of fish passage and fish habitat
SWM facility by pass channel natural channel design
December 2, 2009
September 21, 2010July 21, 2010
June 21, 2010April 1, 2010
2010 Technical Innovation Award
Snow Storage Facility Concept
Stored snow
Inlet
Curb
Oil & grit separator
Sediment forebayPond
Outlet
Three Passive SWM Practices
February 22, 2008 March 28, 2008
April 3, 2008 April 23, 2008
2007 OPWA Technical Innovation Award
Issues in Ontario
• Ontario is faced with increasinggreen field development and urbanintensification, aging infrastructure,climate uncertainties and impacted water courses
• A paradigm shift from end-of-pipe control to a water balance approach using low impact development controls is underway
• Sustainability• Climate Change • LID – Low Impact Development
– Permeable pavements – Bioretention– Dry swales– Rainwater harvesting– Infiltration trenches– Green roofs (LEED designated)
• Environmental integration planning• Watershed based planning
Future of Stormwater Management and Watershed Planning
Low Impact Development (LID)• Definition:
– a stormwater management strategy that seeks to mitigate the impacts of increased runoff and stormwater pollution
– LID practices promote the use of natural systems for infiltration, evapotranspiration, and reuse of rainwater
– effectively remove nutrients, pathogens and metals from stormwater– reduce the volume and intensity of stormwater flows– Goal is to replicate pre-development site hydrology
Source: TRCA CVC November 2008
LID Stormwater Management Practices
PRACTICES INCLUDED IN LID STRATEGIES:
– Conservation Designs– Infiltration Practices– Runoff Storage– Runoff Conveyance– Filtration Practices– Low Impact Landscaping
PRACTICAL EXAMPLES:
– Green Roofs– Bioretention– Permeable pavement– Soakaway pits– Grass channels– Dry swales– Tree clustering– Rainwater harvesting
Sustainability Guidelines for Development and Redevelopment• FCM recently announced that Richmond Hill,
Brampton and Vaughan have received a grant to create sustainable community development guidelines that will aid the development decision making process
• Metrics will be created that will ensure performance levels are feasible and that municipalities are seeing an increase in municipal wide sustainability
Sustainability in Established Neighbourhoods
• Currently no process is in place to increase sustainability in established neighbourhoods
• Resident buy-in is required to increase sustainability • Need to understand barriers residents face to implement LID
and sustainable practices on their property and in their home• Toronto and Region Conservation Authority along with
municipal partners are piloting a Sustainable Neighbourhood Retrofit Action Plan (SNAP) programs in Richmond Hill, Toronto and Brampton
SNAP Program
Program currently being established to “identify ways to accelerate the transformation of existing communities to urban sustainability and increase their contributions to climate change, mitigation and adaptation.” (TRCA, 2009)
– Part of the program will focus on sustainable SW controls that can be implemented into a community
Implementation Challenges
• Public acceptance• Funding – design and construction• Funding – O&M• Complying with official and strategic
plans• Environmental benefits and impacts
Future Practices
Current PracticesWho PAYS for LID?
"The first barrier to the contamination of drinking water
involves protecting the sources of drinking water."
- Justice Dennis O'Connor, Walkerton Inquiry 2002
Climate Change• Is resulting in more frequent
localized intense storms in Ontario e.g. the Vaughan storm in Aug. 2009
• Will affect infrastructure and its ability to perform
• Can cause increased flooding and erosion, therefore having an impact on water quality
mynews.ctv.ca
mynews.ctv.ca
Adapting to Climate Change• National Benchmarking Initiative
– Program based framework• Clean Air Partnership Adaptation Training
– Process based review– Tools and reference
• Public Infrastructure Engineering Vulnerability Committee (PIEVC)– Project specific risk assessment
IDF Curves
• SWM infrastructure generally receives low priority for maintenance and rehabilitation– Could be a liability for municipalities if SW facilities fail
during an extreme storm event resulting in flooding
• Change in hydrological regime requires updating IDF curves– Example: Buttonville Airport IDF graph based on rain gauge data
from 1986 to 1997– There has been a recognizable change in rainfall distribution
and intensity since 1997 and should be included in IDF calculations
But….How do we pay for it all?
• Upgrading Canada’s Infrastructure over the next 10 years is estimated to cost $80-90 billion Source: Infrastructure Canada
• Building LID structures, unknown O&M commitments• SWM infrastructure generally receives low priority for
maintenance and rehabilitation• Watershed protection/improvement projects
Stormwater Financing
• Typically, annual stormwater budgets compete with other vital Town services for financing.
• Relatively new and evolving stormwater legislation and regulations and design standards BUT no new provincial or federal funding sources to meet new stormwater requirements
• Stormwater Financing: provides self-supporting and dedicated funding source for stormwater management
Common Stormwater Financing Methodologies
• Flat Rate• Runoff Coefficient • Intensity of Development Factor• Residential Flat Rate
– Equivalent Residential Unit (ERU) – Single Family Unit (SFU)
• Tiered Residential Rate• Level-of-Service / Geography Base• Impervious Area Measurements
(all properties, each year)
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• Kitchener and Waterloo in 2011 implemented a tiered flat rate fee based on property type and imperviousness
• Aurora, London and St. Thomas have flat rates for residential, commercial and industrial
• Richmond Hill beginning a financing feasibility study in summer 2011
Stormwater Financing
-photos from Totten Sims Hubicki Associates: Kitchener Record, editorial cartoon (7-Apr-06)
Stormwater Research• Trent University
– Urban Water Biogeochemistry and the Role of Stormwater Management Ponds
• University of Guelph• Ryerson University
– Cumulative Impacts Study– Optimization of SWMF Maintenance
• Environment Canada– SW Phosphorus Removal Study
• Toronto and Region Conservation Authority– Cooling Trench Study– Particle Size Distribution Standards for Oil Grit
Separator Performance Review
Discussion
• Stormwater management has evolved considerably since the 1980’s
• Managing our water resources on a watershed basis, looking at the whole water balance system
• Uncertainties remain with regard to – operations and maintenance of LID infrastructure– current state of existing infrastructure with respect to
climate change– the mechanism to fund stormwater and environmental
projects
Questions?