Too Much Pavement

Recent flooding of cities and towns across the world has attracted the attention of an eclectic group of environmentalists, ratepayers and municipal governments.  As our cities have expanded, natural surfaces have been covered by vast swaths of pavement and asphalt. The urban collection of wide roads, driveways and super-sized parking lots has turned our landscapes into waterslides and sluices that quickly deliver storm water overland to rivers, lakes and streams.

Our attempts to make water submit to our will have resulted in the creation of and reliance upon curb-gutter-sewer systems that are supposed to collect the rains and divert them for treatment before they enter the waterways from which we get our drinking water. Yet the legacy of curb-gutter-sewer systems is downstream flooding, erosion, effluent dumping as a result of sewer overflows and ultimately, water quality degradation. They have also been responsible for disrupting the natural hydrologic cycle, reducing groundwater recharge and stream baseflow, while turning self-cleansing systems like filtration and sedimentation into things of the past.

Other sources of water contamination such as industrial discharges, seeps from landfills and dumpings into our waterways have been the target of regulators for decades. While these traditional sources of water contamination have not been completely eradicated, programs to monitor, minimize and moderate have reduced the impact of these practices on water contamination.

But while we were busy minimizing the impact of industrial dumping, urban runoff became a significant source of water contamination. In fact, authorities now cite storm water runoff as the second-largest source of pollution for Great Lakes shorelines.

     Communities are recognizing that the “end of pipe” solutions they once relied upon are failing them in significant ways and are horrendously expensive to install and maintain. Now some communities are attempting to replicate the natural systems that existed before we covered everything with pavement and other impervious materials. These communities are incorporating urban features that retain water, such as rooftop gardens, wet ponds and dry ponds. Any early Canadian farmer or woodsman would be familiar with the techniques that are now being promoted as “green” best management practices.

Unfortunately, our understanding of these practices is sophomoric – we promote the practices without fully understanding the problem. In every municipality one can find self-styled authorities who delight in donning the environmentalist’s green hat. They call for  expanded road surfaces to provide bike lanes; green roofs that are good for moderating a building’s temperature but don’t make a dent in cancelling out the hydrologic damage caused by a Walmart parking lot; and accept without question our apparently insatiable appetite for paving over bio swales, treed lots and vegetation while eschewing helpful options like permeable pavement, eco grids and increased buffer zones as standard development requirements.

One need only look back at our historic development practices and their legacy of a sprawling network of expensive infrastructure along with the ongoing burden of maintaining and upgrading it to realize how wrong-headed our accepted practices have been. Abandoning the field to environmental dilettantes and hobbyists is no substitute for a system wide approach to earth friendly decision making.

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7 responses to “Too Much Pavement

  1. Did you know that the retention basin that is being built on the riverfront at a cost of $66 MILLION will only take care of the sewer overflows between Ouellette Ave. and Walker Rd? Now that is expensive infrastructure!

    Windsor is also a Great Lakes community that is located at an environmental hotspot… this project is a very necessary one for the health of the Great Lakes, which is why it got funded………..

    Maybe we can start using some of the low-tech, low-cost options for flooding in Riverside – some insurer referred to the 1 in a hundred year storm idea as a gambler’s fallacy……… Windsor has had more than its usual share of violent storm events lately…my building (in Riverside) has flooded three times in the last six weeks

    • Vincent Clement

      1:100 flooding is different from flooding due to overloaded sewer systems because of heavy storms. A 1:100 flooding is the level of the Detroit River and/or Lake St. Clair rising and flooding an area.

      A backflow preventer will stop sewer overflow from entering your building. But they are not cheap to install and may require extensive digging and possibly replacing private sewer connections to municipal sewers.

      The City is already using a low-tech, low cost option: disconnecting downspouts from the sewer system and splashing the water over a lawn. It is mandatory in certain areas of the City (however, if the the downspout cannot be splashed safely – ie, disconnecting the downspout would result the water splashing onto a driveway or walkway – it is not disconnected).

  2. Vincent Clement

    That is a nice dig at bike lanes on Riverside Drive East, Carol. Only you could tie bike lanes to poor water quality. I thought encouraging people to bike is an “earth friendly decision”?

    Is Canadian Tire’s parking lot better than Walmart’s? Why the need to mention Walmart? Couldn’t you say “commercial parking lot” or “suburban parking lot”?

    You are losing what little credibility you had.

    Permeable paving is one component of a storm water management system. Even if a suburban parking lot was constructed using permeable paving, the parking lot would still have to be designed to limit runoff to pre-development flows. Permeable paving is most useful where the water table is high (closer to the surface).

    Any parking lots constructed in the past decade are designed to act as storm water retention ponds during heavy rainfalls. Flow restrictors in storm water drains control the amount of water that enters the storm sewer/drain system. Ever been in a parking lot after a heavy storm and wonder why there is a large lake or pond in the parking lot? It’s not because of bad design.

  3. We seem to think that we need too much pavement…..We add more and more of it everyday…I never thought to question it until now………..

    But I agree…We are pavement junkies

    The city struggles to cut the tax burden by outsourcing municipal jobs. It sounds like they could spend some time putting their own house in order and save some money just by changing some of their own development practices.

    I think the most expensive part of paving is the ongoing maintenance cost that it involves. Permeable pavement also has drawbacks – it is twice as expensive as regular mixes and lasts half as long

    Breaking ourselves of the pavement habit would require a new way of looking at the world and that would require that several city departments”switch heads” simultaneously…which I’m not sure they are capable of doing.
    There is no thought as entrenched as that of a civil servant ;)

    • Vincent Clement

      No disagreement that we should revise our own development practices. We could start with narrower right-of-ways and narrower roadway widths.

      But ambulance and fire departments freak out. ‘It will take us 10 seconds extra to get to an emergency’, they say. And since we have been ‘trained’ to believe that the extra seconds matter, people choose streets wider than they need to be.

      Not all civil servants have entrenched thoughts. ;)

  4. Poor Vincent. Put one green solution in front of him and that is all he can see. How it might interact with two or three other green problems seems to be beyond him.

    Adding pavement for cycle lanes is like going to war for world peace. We need integrated solutions to our green challenges, one aspect of which is recognizing the legitimacy of complaints made by those affected by proposed solutions.

    In Toronto for instance they have chosen to provide bicycle lanes on Jarvis Street, not by widening the roadway and laying down more pavement, but by designating former car lanes for bicycles only. Gee, two green ideas encompassed in one.

  5. @wingfan: Are you really comparing Jarvis – a street that cannot be widened – with Riverside Drive – a street that can be widened for bike lanes? Riverside Drive is designated a Scenic Drive in the Official Plan. But apparently some people believe that only those driving or walking should be allowed to experience it. Cyclists should be shunted off to Wyandotte Street.

    Well, it’s all moot because Divisional Court in London has thrown out the suit launched by Riverside Neighbourhood Inc. clearing the way for bike lanes on Riverside Drive. Sanity, common sense and the vision for the whole City of Windsor prevail.

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