Resilient Rainwater Management: Stormwater Management and Adapting to a Changing Climate

RVCA ‐ October 30, 2014

City of Ottawa: “Getting Our Feet Wet” 

with Low Impact Development 

Presentation OutlineresentationOutline

•Evolution of SWM in Ontario  •Local context•Pilots/demonstration projects•What’s next?  

SWM 101

Low Impact Development •Key objective: deal with rain  where it falls• Filter/ infiltrate/ evapotranspirate/detain runoff throughout a site ‐ on lots, within the ROW, in parks, etc.   •LID measures include various bioretention methods, pervious pavements, rainwater harvesting, etc.

Why Low Impact Development?LID offers alternatives that can provide : 

•improved performance by meeting multiple objectives •increased resiliency to severe rainfall events •lower or comparable infrastructure life cycle costs •retrofits in older neighbourhoods that developed with no runoff controls 

Local Context for LID 

Local Context for LID 

Sunnyside Avenue

Stewart Street

Former CFB Rockcliffe  

LID/Retrofit Projects

Sunnyside Avenue

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Sunnyside Avenue

Outlets to the Rideau River

Bro

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Ave

nue

Ban

k S

treet

Sen

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Stre

et Study Area

Rideau River

Sunnyside Avenue

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Sunnyside Avenue

Stewart St. 

The City of Ottawa is considering “greening”  a two block section of Stewart Street to include features that improve the quality and reduce the volume of stormwater runoff in conjunction with the East West Bikeway project. 

• ‘Green Streets’ integrate elements of standard streets such as traffic  lanes for cars, sidewalks for pedestrians and bike lanes for cyclists with features that treat stormwater runoff. 

• Multi‐purpose ‘green streets’ use soil, plants and trees to manage runoff by soaking it into the ground where it is treated. This concept is called “bioretention.”

Stewart 2 Blocks - 290m

Wilbrod

Nelson

King Edw

ard

Friel

Daly

Stewart St. 

• Stewart Street: one‐way street with 2 traffic lanes and a parking lane

• Existing pavement width can be narrowed by up to 2.2 m• Curbs can be extended to increase the boulevard width• Boulevards can be designed to provide stormwater

treatment and more green space in “bioretention” areas

potential bioretention areas/wider planted boulevards

What is being considered for Stewart Street?

LID Demonstration Project

Former CFB Rockcliffe Redevelopment

Former CFB Rockcliffe Redevelopment LID Demonstration Project

Former CFB Rockcliffe

LID Demonstration ProjectCharacteristics:

• Demonstration Project = 11.6 ha

• 920 units of low-rise residential

• 6 local roads (20m ROW)

• 2 minor arterial (26m ROW)

• 2 park and 1 school block

Proposed LIDs: Residential Units

Front Yard Soakaways Subsurface Storage &

infiltration of roof runoff

Overflow to storm sewer system

Source: UCC, 2013

Currie Barricks – Calgary, AB , Source: Aquafor Beech 2013

Proposed LIDs: Residential Units

Soil Amendments 300mm of amended

topsoil over all turf and landscaped areas

8-15% organics pH 6-8 Organics = leaf, yard

waste and food waste in accordance with OMOE & CCME guidelines

Proposed LIDs: ROW

Bioswales Linear bioretention units Planted or turf Local - low use roads

Seattle, WA

Cheltenham, ONMississauga, ON

Proposed LIDs: ROW

Permeable Pavement Parking Lay-bys Concrete Paver units Open graded aggregate

base (no fines) Long-history of

implementation in Ontario Provides water quality

enhancements, run-off detention and infiltration benefits

San Francisco, CA

Mississauga, ON

Proposed LIDs: ROW

Bioswales Permeable Pavement Lay-bys

Planning & Implementation Process

Planning & Implementation ProcessWhat’s Next? 

•Complete pilots/learn from monitoring •Develop LID guidelines tailored to Ottawa•Complete City‐wide Retrofit Plan and implement