Umbrella Stormwater Bulletin 50

18 November 2016
Published by Green Communities Canada

Roads and runoff—using green infrastructure to manage stormwater from roads

Photo: Bioretention planters along the road rights-of-way at Elm Drive, Mississauga, ON, by Credit Valley Conservation. 

During an impending snowstorm last March people piled into Clarke Memorial Hall in Port Credit, Ontario. They were attending a sold-out event to discuss opportunities for managing rainfall in rights-of-way. The key note speaker was Robert Goo from the Environmental Protection Agency in Washington, D.C. A true visionary with real-world experience. Robert celebrated green streets as multi-functional and central to building better communities—with stormwater capture as only one aspect. 

Due to the overwhelming success of his previous presentation, Green Communities Canada will be hosting a webinar entitled Roads and Runoff: using green infrastructure to manage stormwater runoff from roads and highways with Robert Goo on 23 November, 1-2pm EST. During this webinar Goo will discuss what the US EPA has done to enhance right of ways by using green stormwater infrastructure and the resulting benefits of creating green streets. This is the last webinar in the Soak it Up! Fall 2016 Webinar Series. Learn more and register online.

A large proportion of the hard surfaces that make up the urban landscape include parking lots, roads and driveways. In Ontario, there are nearly 200,000 km of roadways creating over 1,100km² of impervious surface – that’s an area greater than the entire city of Toronto! Twenty-five millimeters of rainfall across the province generates over 25 billion litres of stormwater runoff, and millions of kilograms of pollution that runs directly into local watersheds.

Managing road runoff through rain gardens, bioswales, infiltration galleries, or urban trees in the rights-of-way reduces stormwater volumes and stormwater pollution. These practices also make streets safer and more pleasant for pedestrians and cyclists, while sequestering carbon. These features are variously referred to as green infrastructure and/or Low-Impact-Development (LID). 

Momentum for introducing green infrastructure into the construction and reconstruction of roadways in Ontario is slowly increasing. Credit Valley Conservation released have released a manual Grey to Green Road Retrofits: Optimizing your Infrastructure Assets Through Low Impact Development. The City of Toronto will soon be releasing Green Street Technical Guidelines, which will help ingrain green infrastructure into street design practices. 

Innovative projects like The Bentway (formerly known as Project: Under Gardiner) are transforming vacant, impervious spaces in the urban core into vegetated community hubs that capture runoff. The Bentway’s 1.75 km retrofit will change the Gardiner Expressway’s previously abandoned underbelly into a trail and public space. It offers opportunities to manage rain where it falls, treating and infiltrating the water that runs off one of Ontario’s most used highway stretches. 

Projects in the U.S. continue to serve as a source of inspiration and model best practices. [Read more...]


Forward this message to friends and colleague so they can sign upContact the editor with feedback or suggestions on news items.



Ontario Environmental Commissioner releases soil health and stormwater fee reports. This week two reports were released that will be of interest to green infrastructure and stormwater professionals. Putting Soil Health First: A Climate- Smart Idea for Ontario calls for the provincial government to take steps to foster healthy agricultural soils. Quality soil is the most basic form of green infrastructure, absorbing and slowly releasing rain water, and supporting tree and plant growth. The second report, Urban Stormwater Fees: how to pay for what we need, calls on the province to require municipalities to recover the full costs of managing stormwater runoff; by using strategies such stormwater fees. 

Guinea pigs needed for green infrastructure community assessment tool. Green Communities Canada and the Canadian Freshwater Alliance want to help communities change the way rain is managed on the landscape using green infrastructure. We’ve developed an assessment tool that benchmarks progress to date in adopting transformative policies and programs, and helps identify priority next steps. We need five organizations to pilot the tool in their communities and provide feedback on the process and its effectiveness. Interested in knowing more? Contact

Estimating the impact of trees on stormwater. A technology specialist from the U.S. Forest Service and an engineer with the San Antonio River Authority have created a method to estimate tree impacts on stormwater in urban and suburban projects. This will allow municipalities to better understand the effectiveness of trees in mitigating runoff and pollutant loading. 

Green parks for clean water. Multiple cities in the United States have designed their parks to filter and absorb excess rain water. According to The Trust for Public Lands, these parks have become publicly appreciated green spaces that provide a focal point for community recreation and tourism. The successes and challenges of creating water-smart parks are featured in their report City Parks, Clean Water.

Sponge parks soaking up water in Superfund site. A park in New York is being designed to divert one million gallons of runoff water from discharging directly into the Gowanus Canal. According to the Environmental Protection Agency, the canal is one of the most polluted bodies of water in the US. The park will use woody plants to absorb, filter, and evapotranspirate water through their roots and leaves, as well as remove toxins from runoff through phytoremediation. At least two other Sponge Parks are scheduled to be built along the canal. 

Getting the message right. A study from the University of Delaware has found that people prefer to invest their money in conservation such as protecting key areas of watershed (green infrastructure), rather than traditional water treatment plants (grey infrastructure). Different messages related to climate change, global warming, extreme weather events and decaying infrastructure affect people’s willingness to contribute to projects. Referring to large catastrophic storm events actually decrease the likeliness of people contributing because these events are perceived as being out of people’s control.


Stormwater Master Planning using Grey and Green Infrastructure. Credit Valley Conservation has released the fifth in its series of Grey to Green Retrofit Guides. The guide supports municipalities in retrofitting stormwater management systems using both grey and green infrastructure through completion of a stormwater master plan. The guide also promotes an approach to stormwater management that considers a watershed context. (Below: photo provided by Credit Valley Conservation). 


Roads and runoff — using green infrastructure to manage stormwater runoff from roads and highways. Webinar. 1-2pm (EDT). 23 November 2016. Presented by Robert Goo, Office of Research and Development, USEPA. Register online.

Lessons Learned in LID Construction. Webinar. 8 December 2016. Hosted by Sustainable Technologies Evaluation Program. Register online.

Want to see more events? Check out the RAIN Events Calendar for other upcoming green infrastructure workshops, training, webinars and conferences.

The Umbrella Stormwater Bulletin is a free, monthly newsletter on green stormwater infrastructure published by the RAIN Community Solutions program of Green Communities Canada. Our audience is made up of municipal stormwater professionals, policymakers, academics, engineers, conservation authorities, nonprofits, and interested community members. We encourage submissions from our readers. Please contact the editor to submit a news item, blog idea, or event. RAIN Community Solutions builds support for and participation in stormwater innovations that reduce runoff by managing rain where it falls.

Copyright © 2016 Green Communities Canada, All rights reserved.


unsubscribe from this list    update subscription preferences 

Email Marketing Powered by Mailchimp