Monday, December 15, 2014

Rainfall Event Stresses Sewage Outfall Pipe

 Signs warning public of sewage pollution
 Roadway had to be built to bring in equipment
 Excavation is right on the property line of the adjacent home
Excavation has now revealed area of damaged pipe to be repaired

The outfall pipe slated for replacement this year wasn't able to withstand the additional pressures put on the system by a combination of the rainfall event and the king tides. The damaged pipe was first noticed by a resident of the property bordering Morningside Park. While checking for any rainfall issues on his property the owner noted water gushing up out of the ground.

The repair of this leak has turned into a major construction project which first required the building of a temporary road through the park to move in equipment and also the removal of trees which had concealed the neighbouring home.

Because of slope stability issues and the proximity to the neighbouring home a geotech specialist is on site supervising the ongoing excavation that has now revealed the damaged pipe, which is still an active sewer line. It is treated effluent in the pipe and most of the flow is carried through the two kms to the final outfall by Hudson Rocks. 

This repair has presented crews with some serious challenges not the least of which is plugging a hole in a sewer line that can't simply be turned off to make the repairs. There are holding ponds in the system which can be used to divert the flow for 3 - 4 hours maximum, during which time it is hoped a repair can be made to the pipe.

This past summer a new outfall line was run from the treatment plant to Morningside Park but will not be put into service until the new outfall pipe is installed which consists of about two kilometres of pipe running underwater from Hammond Bay to Hudson Rocks.

The design phase of the marine portion of the project has now been awarded and when complete the contract to install the underwater outfall will go to tender. It is hoped this work can be completed this summer as it can not be done during the stormy fall season. The entire project is expected to be in the $18 million + range and will be replacing pipe that was expected to have a life cycle of 70 years but is needing replacement after only 45 years.

allvoices

1 comment:

  1. They don't make things like they use to

    ReplyDelete

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