Potential breach forces dam repairs

Efforts are underway to ensure the integrity of Greater Vernon dams and to prevent a disaster.

Efforts are underway to ensure the integrity of Greater Vernon dams and to prevent a disaster.

The Greater Vernon Advisory Committee voted Thursday to spend $270,000 on outlet pipe repairs to the Haddo Lake dam on the Aberdeen Plateau.

“It is a safety issue so we need to do it this year,” said Zee Marcolin, water utility manager.

“If the dam were to breach, it (flow) would go to the channel, hit the Headgates dam and go into Lumby.”

In a report to GVAC directors, Marcolin says structural failure could be “catastophic.”

It was identified in 2006 that  grout in some joints in the concrete outlet pipe were failing and the outlet structure was showing signs of deterioration. An engineer recommended that repairs be completed and in the interim, the condition of the structure was monitored.

As part of final design work, a video of the outlet pipe was conducted and it identified leaking joints.

The work will occur between Sept. 15 and Oct. 31 when irrigation demand has ended because the outlet structure needed to supply water must be bypassed.

Beyond Haddo, staff have also been looking at the Grizzly and Aberdeen dams, which are rated as high consequence structures in the event of a failure.

“These dams are from the 1960s,” said Marcolin.

“There’s a joint we’re fixing on the Aberdeen dam and another issue is to look at the design for the Headgates. The spillway is undersized. It will be designed and work will be done next year.”

Awareness over dam integrity arose after a private dam failed near Oliver in 2010 destroying five homes and farms.

Director Bob Fleming is pleased to see staff focused on the dams.

“They are on top of the issues and there is a program for maintenance. I am satisfied,” he said.