Many great cities of Europe are beginning to uncover rivers and streams that were channelized and covered in the 18th and 19th centuries to facilitate new sewer systems and to create room for infill.
Fleet Street, named after the river flowing from North of London to the Thames, has been covered so long, many Britons are unaware that it even existed. Today, dozens of Thames tributaries are being uncovered, and wetlands restored, as new demolition and site remediation allows. The site of the 2012 Olympic village was that of the world's first plastic factory and support industries, making it one of the most polluted urban areas in Europe. The village now sports reflecting ponds, wetlands supporting wildlife, and an uncovered (or day-lighted) river Lee. With the success of these programs (which are expected to take a century to complete) and the clean up of the Thames 40 years ago, the watershed of the area is realizing a health and vitality that hasn't existed since early medieval times.
In Leduc, we are fortunate that we have a park system that protects Deer Creek and policies that protect Telford Lake from the drainage faux pas of past decades. Deer Creek, which originates SE of Leduc, flows across Hwy 2 near the weigh scales, winds through the golf course and reservoir, past Bridgeport and West of the airport. Ultimately, the stream enters Blackmud Creek and flows into the North Saskatchewan River near Fort Edmonton, making it an important regional feature. The City also contains many drainage patterns that feed Deer Creek, other regional streams, as well as Telford Lake.
Keeping natural streams and grass waterways day-lighted and functional is important to the environmental health of the community, and safety of residents. The old engineering paradigm is to
build impervious surfaces, and create a need for large and effective storm drain systems. Put everything underground (out of sight - out of mind) at great expense, requiring frequent maintenance (r-o-w's must be kept clear), and shoot water out of the community as fast as possible, and don't worry about the consequences downstream (high velocity, scouring, flooding, and pollution). The new philosophy is to improve the cultural, ecological, economical, hydrological, and recreational aspects of urban areas by keeping streams open and accessible to people, wildlife, and for storm water management.
Day-lighted streams upgrade quality of life and aesthetics for residents, restore local identity, increases public engagement, and creates educational opportunities for the public and schools. Day-lighted streams encourage the return of wildlife and birds to neighbourhoods, improves water quality through vegetative filtering (cattails, etc.) of sediments, toxins, and fecal matter. Natural vegetation absorbs nutrients (e.g. chemical fertilizers) to reduce toxic effects and algae blooms, and the exposure of contaminants to air, sunlight and soils helps to transform, bind, or otherwise treat contaminants. Day-lighted streams allow soil water permeation, and more vegetation means more carbon sequestration. Natural streams revive urban decayed areas, increase local property values by 50%, and eases and reduces need for maintenance and construction of complex underground systems. Open steams reduce flood damage (storage and flow options). Natural, winding streams with buffers can provide greater hydraulic capacity than sewer pipes, reducing storm water flow velocities and erosion, and assisting sediment filtering, bank stabilization, controlled water storage and release, and aquifer recharge. Lastly, open streams help to provide and enhance opportunities for trail systems and other recreational activity, and provides more "functional" greenbelt and park space.
This can only happen, though, if urban municipalities embrace the protection of natural drainage patterns, waterways, and wetlands and value them for their functional abilities. We're lucky in Canada, unlike European countries, who have to recreate ancient waterways. Ours are still here to embrace and use wisely. Question is...will we?
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