Umbrella Stormwater Bulletin 45
15 June 2016
Published by Green Communities Canada
Green Islands for blue water
In collaboration with Jon MacMull, Supervisor, Marketing & Communications, Credit Valley Conservation
Stormwater management ponds have long been the infrastructure of choice for managing runoff from roads, parking lots and other impermeable surfaces. While stormwater ponds do a good job of slowing the surge of water during a rain storm and collecting sediment, they often do little to treat pollution. Further, standing water often experiences an increase in temperature. Warm water has lower levels of dissolved oxygen and can have a detrimental impact on aquatic species living in streams receiving water from stormwater ponds.
In order to mitigate these negative impacts, Credit Valley Conservation (CVC) is monitoring the benefits of floating islands in stormwater management ponds. One pond in particular (which drains into Fletcherâ€™s Creek in Brampton) has been the focus of an extensive monitoring program over the past two years.
Floating islands are engineered vegetated rafts made of natural or inert materials. The roots dangle into the water, and absorb nitrates, phosphorus and ammonia. Floating islands have also been found to be effective at removing total suspended solids and dissolved organic matter.
The islands also shade the water as the vegetation grows. This can lower water temperatures, which is especially important in the centre of larger ponds where shoreline vegetation does not provide shade.
Results from the Fletcherâ€™s Creek stormwater management pond have demonstrated a variety of benefits....[Read more]
Ontario growth plan to incorporate green stormwater infrastructure.Following a recent review of regional land use plans in Southern Ontario, the government has issued proposed changes that will affect the way rain is managed in the Greater Golden Horseshoe Area. The summary guide, Shaping Land Use in the Greater Golden Horseshoe, states the changes would: â€œEncourage the use of green infrastructure and require low-impact development techniques that include integrating green space in design strategies, landscaping with native plants, and using natural water systems to generate less runoff from developed land.â€
Green bonds for blue cities.The San Francisco Public Utilities Commission is the first entity in the world to issue a green bond certified under the Water Climate Bonds Standard, a screening tool that specifies the criteria that must be met for bonds labelled as â€œgreenâ€ or earmarked for funding water-related, low carbon initiatives. Proceeds from the bond will fund projects in sustainable stormwater management- a first step in providing long-term financing for green infrastructure. The value of dirt. Industrial activity, pollution, and exploitation are degrading the quality of soils located in and around cities, according to a report released by the European Environment Agency (EEA). The efficient use of soils supported by better planning and policy is needed to ensure that this valuable natural resource helps our cities remain liveable and able to deal with challenges like climate change.
Soaking up water, curbside. The New York City Department of Environmental Protection has begun building 321 rain gardens in strategically selected locations that will be able to absorb up to 9400 L of stormwater- for a total of 143 million L of stormwater per year. The gardens will be constructed based on a standard design, specifications, and procedures as outlined by the City.
Flooding and green infrastructure. The degree to which using green stormwater infrastructure helps to manage floods is unknown. No one is arguing that GSI will eliminate massive flood events but demonstration sites such as Elm Drive in Mississauga, ON can reduce peak flows for 2- year events by 70- 100%.
Canadian students LID competition. The Ministry of the Environment and Climate Change and the Water Environment Association of Ontario are once again challenging Canadian students to apply their knowledge to help mitigate real world, environmental problems. This year the Student Design Competition will be hosted in the City of Toronto with and will have a stormwater/ low impact development theme.
Online resources to support sustainable landscape solutions. Geared towards landscape designers and advocates of sustainable landscaping, the Landscape Performance Series has a variety of searchable resources to help evaluate the performance, show the value and help make the case for sustainable landscape solutions.
City Green: Innovative Green Infrastructure Solutions for Downtowns and Infill Locations. Created by the US Environmental Protection Agency- this document is a compendium of 12 case studies showcasing projects that have overcome green infrastructure challenges in downtown and infill locations. It provides inspiration and helps to identify strategies and lessons learned for overcoming common barriers, such as space, and soil conditions that are unsuitable for infiltration.
Managing stormwater through low impact development. Webinar. 22 June 2016. 12-1pm (EDT). Presented by FCM's Green Municipal Fund and Green Communities Canada. It's free but online registration is required.
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.