Sink hole repairs get complicated
June 25, 2008 · Updated 11:00 AM
The 1.8 metre (six feet) deep sink hole that opened up in the southbound lanes of 200 Street near 53 Avenue last week has led operations crews to believe there could be more pipe problems down the road.
There are concerns about the integrity of the piping. Corrosion may be extensive. Once they (the Greater Vancouver Regional Distirct) opened it up, they had a better opportunity to see whats inside. They may be looking at doing more rehab on the sewer main line in the future, said City manager of engineering operations Dan Mooney.
The main line runs down the middle of 200 Street.
The sink hole was discovered last Thursday, when a vehicle crashed right into the 1.2 metre wide (four feet) crater.
We determined that the cause was from the GVRDs sanitary sewer trunk line which had a significantly sized broken pipe, said Mooney.
It had been syphoning off gravel between the pipe and the road surface for some time, creating the sink hole. The City shut off its water lines so GVRD crews could start excavating the remainder of the hole and get to the piping to find the cause.
Work to fix the pipe became complicated earlier this week because gravel and pieces of pipe had gone into the line, blocking the sewage flow, said Mooney.
GVRD crews had to create a small service road on the Nicomekl floodplain to access a manhole to clear out the trapped debris.
The GVRD had environmental consultants come in to make sure the service road was built properly, he said.
The repairs were completed Thursday with all four lanes of 200 Street likely open by Friday afternoon, he said. A PVC plastic pipe was inserted into the existing concrete pipe.