Flooding and "Backflow preventers"

On August 4th 7.5 inches of rain fell over 8 hours damaging 3,000 plus homes and flooding many with storm water and sewage discharge. This should serve as a massive wake up call for us all. Experts have been reporting the likelihood of increased weather of this type for some time. Due to the unprecedented amount of rain, some damage was probably inevitable, but several issues spread the damage to houses that might have been spared. Conservation Halton gave Burlington an F grade for a large percentage of ground covered by pavement. One of the effects that this produces is increased flooding. This extra water was channeled into an outdated sewer system which magnified the problem. What we can not do is leave thousands of residents in fear that a repeat will disrupt their lives again.

I think we have to take this issue of flooding connected with ground cover seriously. Though 7.5 inches of rain fell that day, sandy soil in optimum conditions could have absorbed 6.5 inches of rain leaving just 1 inch of run off. Since the area was developed, a much larger amount of run off would have occurred in any case. The point is open soil can absorb a tremendous amount of water. We should identify low lying areas typically considered just outside the flood plain and work to zone them for a large percentage of open ground. Halton already works out the flood plain and prevents building in it, but in light of this disaster it might be wise to increase the safety factor they use. In any case we need to think seriously about protecting the remaining open ground that can be used to drain water away. It's not “wasted space” if it prevents millions of dollars in damage to home owners. 

The other issue is one of discharging storm water into the sewer. There are two types of “drains” around your house. One connects to the sewage system run by the city. The other is designed to take away storm water run by the region. Previous to about 1975 it was normal to use the sewage system to take away both types of water. The volume of this combined water got too great to easily process and cities decided they wanted storm water left on your property or discharged into the storm drain. Older houses have this unified setup where storm water goes into the sewer. The city fully realizes that previous to 1975 the setup was acceptable and from older areas flood water comes down the sewage line as well as waste. The city decides how many people can connect to a sewage line safely by essentially choosing the amount of water it can move before a disaster occurs. It is the city's responsibility to size sewage lines or limit the connections to them. Obviously the system can not handle 7.5 inches of rain in the flooded area with success. How much it can currently or should be able to handle should be the conversation. Other areas with the same amount of rain did not experience the same problems. The region needs to choose a reasonable standard of service and enforce it. I don't think the city should “throw it's hands up” and declare we can no longer reliably handle waste water - everyone go get a “backflow preventer”. If the city can not increase the waste water capacity to a level that ensures the safety of homes, they should not be allowed to issue permits for still more housing.

“Backflow preventers” are not a solution. Though they can possibly save your property, they can also easily jam on the normal material found in sewage. If your back flow preventer jams and your neighbours' function, then your house will bear the brunt of the event at much higher flooding levels. Even with a preventer, any water you use in your home will back up at the shut preventer. You will still “discover” that an event has occurred when you notice flooding in the basement. It will be with your own waste water and a much smaller amount, but you will still have water in the basement. The industry solution to this problem is to pump the sewage around the preventer, allowing some residents to function normally while literally pumping sewage into houses next door. I don't see how we can permit any system that allows one resident to damage another via city pipes. In the case of power failure a battery backup is used to run the pumps. Equipping thousands of houses with this complicated preventer-pump-battery system seems incredibly frail. All the city needs to do is provide large concrete pipes on an angle and holding pens at strategic points to erase this problem from home owners. I understand that the water concentrates at certain points creating tremendous technical challenges, but these points of concentration are created by the design that the city selected. Storm water is better stored almost any place than residents basements.

Burlington's and Halton's current response is insulting. I can not see any reasonable argument that would allow the city or region to deflect any responsibility for this failure. The city permits and inspects every aspect of the storm water and waste water system. The idea that an “unmanageable” amount of rain fell is ridiculous. The amount may be unmanageable for the number of residents hooked to the existing system with unified connections, but the city allowed that number of residents to connect. If all houses were removed except one, would sewage back up have occurred? Of course not. The city has gone over the number of house holds that the system can safely sustain during high levels of rain. The city sets all these limits, residents control none of them.

Where the unified waste water system is unworkable the infrastructure should be upgraded by installing large storm water drains and connecting the residents to those pipes underground. Older areas just need brought up to the standard of newer areas. It's a big expensive upgrade, but at the end residents are secure from waste water backup. This system protects residents with simple concrete pipes and gravity. Because the city finds this process expensive and difficult it's attempting to escape the cost with “backflow preventers”. Upgraded infrastructure is the only way to stop a sick lottery where some preventers, pumps or batteries fail during an event and destroy a smaller number of homes more completely. It's completely unacceptable.

Cities in combination with the region must enforce a quality of service guarantee to residents. The city needs to certify the system is able to handle a specified amount of rain run off. Universally applied this type of hard and fast guarantee prevents the city from invisibly skimping on safety margins as these systems come under cost and development pressure. If we rebuild confidence in the system then insurers will recalculate a low chance of failure and re-establish high limits for waste water back up damage. This protects all residents via low cost insurance and is the only solution. Unless you can re-enable insurance, all home owners are in constant jeopardy. No matter how expensive a system a home owner installs everyone is a simple jam away from having a flooded home. The city must offer security to residents for the services it provides. Again, If it can not supply these guarantees then we can not increase the population when services to existing residents are failing.

I don't think the current “we can't do it” mentality is isolated to waste water backup. The region seems to be attempting to solve a larger list of issues by exporting the problem on to the back of residents. The next best example being transit where the “official plan” is little more than trying to make people feel guilty unless they walk, bike or stay home. Halton's preferred transit strategy is “Transit Demand Management” where residents learn their transit habits are “Unsustainable” and stop traveling. This seems to be a similar mentality to me. A major factor in my run for Regional Chair is that I find this mentality completely unacceptable. I don't see any way to reverse this without massive community engagement. Please e-mail, tweet, Facebook, or have your neighbours for coffee and educate them on these issues. You educate five people, they educate five people and so on. All of a sudden, you will elect people that will start getting this trend reversed.

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