Replacing water main on 107th Avenue
FTLComm - Tisdale - Wednesday, August 4, 2010

The original water system for Tisdale was installed using cast iron pipe. Though normally permanent and durable the electrochemical makeup of the clay soil under Tisdale reacts unfavourably with these cast iron lines and holes develop from the static build up of water passing through the pipe and the soil through which they pass. The solution is a costly one but each year the town digs up and replaced about two blocks of cast water main and replaces it with plastic pipe.

This year work has begun on 107th Avenue between 99th and 98th Street. The pavement has to be removed on the south side of the street then the whole block will be excavated removing the old cast pipe and replacing it with plastic.

Since this is a street the backfilling is extremely important. First the new line is backfilled with gravel which is packed during the process then the fill material is replaced and packed layer by layer back down so that there will be a minimal amount of settling in the first two years. The top layer of backfill is gravel to form a street base.

It is the normal practice to let the street lie in this gravel state for at least a year and sometime two or more before the street is repaved.