Here is a letter from Delta resident and veteran civic affairs watcher Peter Duffey, reprinted here with his permission. He is affiliated with Save the Southlands Committee. On July 29, 2013 Delta Municipal Council passed first and second reading of an application by Century Group and sent it to Public Hearing set for October 28. The issue? A major development on 531 acres of prime agricultural land known as the Southlands, in Tsawwassen.
Century’s Southlands proposed development is too risky
Their own engineering consultants have identified the area as subject to ”moderate” liquefaction in the event of the statistically overdue earthquake.
This assessment appears to minimize as far as possible the dangers of developing this land for residential development.
However the information contained from the insurance industry identifies the land as subject to a “very high” probability of liquefaction. Please read the article from B.C. Business magazine (The Cascadia Fault: An Inconvenient Truth, by Steve Burgess, Aug 5, 2013. Excerpt: Four more codes fall into the “Very High” [risk] category—V8N and V9B in Greater Victoria, V4L in Delta and V4R in Maple Ridge. ).
A geotechnical and engineering report commissioned by the Century Group can be found on the Delta municipality webpages. This recommends that the widely accepted year 2100 high water forecast level be used to develop flood protection.
The report calls for use of a flood construction level of 4.8 meters and recommended the construction of a very large berm to allow a lower flood construction level of 3.5 meters. This was assessed as needing 140,000 truckloads of fill.
The proposal has been revised. The use of the year 2100 high water forecast level has been abandoned. The device of a 6 meters easement to allow a gradual sloping before construction, and the adoption of a flood construction level of 4.2 meters would make the buildings vulnerable to the expected 2100 high water level. See diagram.
Further, most garage parking is proposed to be beneath the flood construction level. The provisions of the B.C. Local Government Act do not allow such space to contain anything which can be damaged by flooding.
We now see that there is a reduced forecast of the amount of fill, which is quoted at 60,000 truckloads. One Delta councilor who is obviously in favour of this development pronounced his satisfaction with this reduction. However, I wonder if he has realised that this has been achieved by markedly reducing the protection level for residents who may have to live in this area.
What is abundantly clear is that if Delta approves this development in its present form it will be a party to a proposal which is excessively risky.
Delta Council and staff need to be asked why they are going along with a proposal which does not take into account the 2100 expected high water level, and why they are accepting a development plan for land which has a very high risk of liquefaction.