The information session did not have too much new information beyond the press release and the document that we received back in December. The purpose of this meeting was to solicit resident questions and concerns, gather them all together with the idea that they will answer some of the questions in a future presentation.
There was a presentation at the beginning then we were left to discuss things with a smaller table of residents along with a city outreach person.
Some new to me information:
The proposed berm is part of a three-part solution for flood preparedness. The first part of the solution is the agreement with Transalta and others for controlling water levels in the Ghost, Bearspaw and the Kananaskis dams (which have been in place for a while).
The second part of the solution is that they are exploring building another dam upstream and they have three locations in mind, but that solution will take decades because it involves 3 levels of government plus the native bands upstream.
The berm is the third part and they want to move ahead with it because it is something the city can do on its own. It will not be built to withstand the 2013 level of flooding, but instead will be intended for a 20 year flood event (like 2005) with some overbuild.
The idea is that with the three in combination (berm, dam control and new dam), flood damage will be mitigated up to the 100 year flood level (which 2013 was not), but that any individual measure will not work on its own.
The berm will also be built as a result of negotiation with each river-lot owner. The city will not be appropriating that land, but rather will be purchasing a permanent easement on each lot from each homeowner, and may well adjust the design based on individual owners' concerns. (I'm skeptical about this last part)
I asked about Montgomery and got no answer, but I would be surprised if there isn't something planned for there. I also asked about the effect of clear-cut forestry in the Bow River catchment and whether that was considered in the cost benefit analysis.
Most residents were concerned about berm effectiveness because most of the houses are built on gravel and so we have serious groundwater concerns. The answer we got was that they will be drilling holes to do a hydrological study, but that they don't mean to dig all the way down to bedrock beneath the berm, rather the rough plan would be for a 1m excavation and clay fill to make the groundwater flow path be more torturous and slower.
|