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Project Neutral Transforming Riverdale and The Junction into
Low Impact Neighbourhoods
RiverSides The path to clean water begins in your own
backyard
5 Things You Can Do For the Don (Toronto) 1996-1998
WaterLinks/CommunEAUté (City of Ottawa) 1998-2001
Nine Mile Run RainBarrel Initiative (Pittsburgh) 2003-present
RiverSmart Homes (Washington, D.C.) 2004 - present
RiverSafe Communities
Homeowners’ Guide to Rainfall (www.riversides.org/rainguide)
Municipal Low Salt Diet**
Water In the City Walk**
RiverSafe Carwash Campaign**
RiverSides is the R&D design home of Resilient Rain; our vision and passion to protect rain, where it falls, and the clean rivers that flow from doing so.
Resilient Rain transforms neighbourhood rain barrel programs from discrete, unproductive, and unreliable into a stormwater smart grid for providing effective, reliable and resilient residential LID.
Watersheds and
Stormwater Runoff
Runoff
Very little Runoff
Top Soil
Q
T
2
3
4
1
5
6
7
Hydrograph Summary 2
3
4
1 Existing
Developed, conventional CN, no control.
Developed, conventional CN and control.
Developed, LID-CN, no control.
Developed, LID-CN, same Tc.
Developed, LID-CN, same Tc, same CN with
retention.
Same as with additional detention to
maintain Q.
5
6
7
Pre-development
Peak Runoff
Rate
Where Does a River’s Water Come From?
• Tableland run-off constitutes a majority of a river’s flow. Howard, Ron:
University of Toronto, 1996
• In most urban centres a river’s flow is subjugated to the land form of the street and the pipe.
• This is known as the sewershed.
How do you maintain the ecological integrity (ecosystem
functions) of aquatic systems (streams)?
Chemical
Variables
Flow
Regime
Habitat
Structure
Energy
Sources
Biotic
Factors
Nutrients
Temperature
D.O. pH
Turbidity
Organics Toxics
Disease
Reproduction
Feeding
Predation
Competition
Sunlight
Nutrients
Seasonal Cycles
Organic Matter
1&2 Production
Canopy
Siltation
Gradient
Substrate
Current
Instream Cover
Sinuosity
Width/Depth
Channel Morphology
Soils Stability
Riparian Vegetation
Velocity
Frequency
Runoff
Evaporation
Ground Water
Flow Duration
Rain Intensity
Scale / Spatial / Temporal / Species
Ecosystem
Integrity
Goals / Objectives
• Community Engagement
• Supportive Follow-up
• Reduced Combined Sewer Overflows and Stormwater Runoff
Daddy, What’s A Sewershed?
Urban watersheds consist of a labyrinth of combined (sanitary) and storm sewers.
Tributaries and creeks were buried in combined sewers replacing the watershed with piped flow.
By the 1950s, combined sewers were separated into street sewers and semi-combined (roof downspouts connected).
New developments sometimes connected roof downspouts to storm sewers.
Conventional Development
Bad Drainage Paradigm
Every aspect of a site is designed to get
rid of runoff as quickly as possible -
buildings, lawns, streets, etc.
Soil Modifications
• Clear Vegetation
• Remove Top Soil
• Compaction
• Change Grades
• Modify Drainage
• Destroy Biological Activity
• Destroy Soil Structure / Function
Conventional Drainage
Paradigm
The Problem: Conventional Site Design
Compaction
Cover
Collect
Concentrate
Convey
Centralized
Control
Conventional Pipe and Pond Centralized Control
“Efficiency”
Street
Storage?
Low Impact Development
Conservation
Minimization
Soil Management
Open Drainage
Rain Gardens
Rain Barrels
Pollution
Prevention
LID Development
Disconnected
Decentralized
Distributed
Multi-functional
Multiple Systems
Uniform Distributed Small-scale Controls
Maintaining Natural Hydrology Functions
LID’s distributed
control opportunities
are unlimited when you
think small.
Low Impact Development (LID) Goal
Maintain and/or restore hydrology and water quality in developed watersheds to protect ecosystems, meet regulatory requirements and achieve local water resources protection objectives.
Approach
A sophisticated technological approach to water resources/ecosystem protection/restoration using new management paradigms, innovative lot level control practices and pollution prevention measures.
Strategy
Cumulative benefits of LID principles and practices maintain and/or restore watershed functions in urban neighbourhoods
Five basic steps to LID
1. Conservation
2. Minimization
3. Strategic Timing
4. Integrated Management Practices
5. Pollution Prevention
Urban LID Lot Level Control Opportunities
• Roofs
• Buildings
• Downspouts
• Water Use
• Yards
• Sidewalks
• Streetscapes
• Parking Lots & Structures
• Landscape Areas (trees/vegetation)
• Open space
• Pollution Prevention
Multifunctional
Infrastructure
Evaporate
Infiltrate
Retain
Detain
Filter
Use
LID Volume / Timing / Treatment
Engineer a site using micro-scale techniques to mimic water cycle ecosystem functions / relationships. Creative ways to maintain or restore:
– Storage Volume
• interception, depression, channel
– Infiltration Volume
– Evaporation Volume
– Runoff Volume
– Flow Paths / Timing / Frequency
– Treatment with Soil / Plant Complex • Biological / Physical / Chemical (soils)
LID Suburban Development Approach
Conservation
Minimization
Timing
DIMP’s
Pollution Prevention
1. Conservation Plans / Regulations
• Local Watershed and Conservation Plans – Forest (Contiguous and Interior Habitat)
– Streams (Corridors)
– Wetlands
– Habitats
– Step Slopes
– Buffers
– Critical Areas
– Parks
– Scenic Areas
– Trails
– Shorelines
– Difficult Soils
– Ag Lands
– Minerals
Conservation Design GoalsConservation Design Goals
•• MarketabilityMarketability
•• Quality of LifeQuality of Life
•• Maintain Same unit yieldMaintain Same unit yield
•• Protect Natural Resources (50%)Protect Natural Resources (50%)
•• Interconnected Network of Open SpaceInterconnected Network of Open Space
•• Cluster Reduce Infrastructure CostsCluster Reduce Infrastructure Costs
•• Sense of Place with Nature as a PartSense of Place with Nature as a Part
•• Development of a Land EthicDevelopment of a Land Ethic
•• Conventional Stormwater ManagementConventional Stormwater Management
2. Minimize Impacts
• Minimize clearing
• Minimize grading
• Save A and B soils
• Limit lot disturbance
• Soil Amendments
• Alternative Surfaces
• Reforestation
• Disconnect
• Reduce pipes, curb and gutters
Better Site Design GoalsConsensus Recommendations
• Reduce Impervious Surfaces
• Conserve Natural Resources
• Reduce Stormwater Impacts
• Compact Development
• New Development
• Quality of Life
• Conventional Stormwater Management
3. Maintain Time of Concentration
• Open Drainage
• Use green space
• Flatten slopes
• Disperse drainage
• Lengthen flow paths
• Vegetative swales
• Save headwater areas
• Maximize sheet flow
• Maintain natural flow paths
• Increase distance from streams
4. Storage, Detention & Filtration • Uniform Distribution at the Source – Lot Level Storage
– Open drainage swales
– Rain gardens / bioretention
– Smaller pipes and culverts
– Permeable Paving
– Small inlets
– Depression storage
– Infiltration
– Rooftop storage
– Pipe storage
– Street storage
– Rain water Use
– Soil management**
LID
Development
Structural
BMPs
5. Pollution Prevention
• Maintenance
• Proper use, handling and disposal
– Individuals Lawn / car / hazardous wastes / reporting / recycling
– Industry Good house keeping/proper disposal/reuse/ spills
– Business Alternative products / Product liability
80 % Reduction in N&P
Kettering Demonstration
Project
Using Rain Barrels to Manage
Residential Storm Water
Curb
Street
Storm Drain
High Rate
Biofilter
Side Walk
Tree
Inlet
Tree Box Filter
LID Residential
Techniques
Multi-functional
Swales Rain
Gardens
Tree Conservation
Rain Barrels
Amended
Soils
Ecosystem
Based
Design
• Rain barrels ‘work’ day in and day out to catch rain before it runs into the storm drains
• Connected to your downspout, rain barrels collect rain water whenever it rains
• When it isn’t raining, rain water stays in the barrels waiting to be used on your garden and lawn
Rain Barrels
• RiverSafe Rain Barrels are secure and safe
• One piece design, UV-stabilized Low Density Polyethylene
• No warping, fading or cracks, covered and impenetrable to animals, insects and mosquitoes
The RiverSafe Rain Barrel
2 Stage Filtration System:
• Stage 1: retains leaves, twigs and roofing materials
• Stage 2: 200 micron mesh makes each rain barrel mosquito safe, and filters out sediments and fine particles
Downspout
Disconnects /
RainHarvestig
Runoff Capture
Piped
Consumption
Reduction
Limit Stormwater
Fees
Total Water Management Rain
Barrels
Rain
Gardens
Seeing It All From A Lot Level Perspective
Cities are made up of individual lots and stormwater begins where rain falls… so does the solution.
If it reaches the street grate, you’ve lost more than half of the opportunity to make a difference…
Lot level source control utilizes a combination of practical technology, natural systems, and pollution prevention.
Whether we refer to the process as Smart Growth or Low Impact Development, the result is to re-establish the pre-development hydrologic regime.
We accomplish this by recognizing the factors that we have to deal with, and what we can accomplish to prevent CSOs and stormwater flows.
Lot Level Methods for Stormwater and CSO Attenuation
•Rain Barrels
•Downspout Disconnections
•Rain Gardens and Swales
•Driveway Grates
•Street and Yard Trees
•Naturalization/Re-grading
•Permeable Pavers
•Soakaway Pits
•Rooftop Gardens
Riverdale and Junction Neighbourhoods
Semi-Combined Sewer System – City of Toronto
Downspout Disconnection
How Much Water Does A Rain Barrel Store?
The Canadian Calculation
• A 500 litre RiverSafe RainBarrel stores 18.87m3/home with a 50m2 average roof size in an average year.
The US Calculation – Rainfall density x Roof Area per downspout = Volume
– Measurement • ¼” Rain x 350 sq./ ft. (average roof area per downspout) = cubic feet of volume
What Do I Look For…
In A Rain Barrel?
• West Nile Virus (Mosquito) Proof
• Children Proof (Enclosed)
• Freeze –Thaw Tested and Winter Capable
• Large Enough – Size Does Matter
• Ease Of Installation and Maintenance
• Social Marketing Follow-up Service
Potential Problems?
• Lack of Permeability
• Grade of Property to Structure
• Tree Roots
• Price Equity/Accessibility
• Neighbours’ Inadequate Understanding
Solutions!
• Partnerships: Municipalities, community members, local organizations
• Good Communications Materials
• A Great Logo
Community Partnerships for Clean Water
Building Partnerships with Your Municipality
• Why Should They Work With You?
• What Role Can You Contribute?
Social Marketing Your Project
• Focus on Action over Education
• Get A Written or Verbal Commitment
• Focus on ease of implementation
• Offer Reinforcements – Incentives
– Follow-up
– Education
• Ask For Greater Commitment As the Project Progresses