The Colliery dams will still fail to meet B.C. dam safety regulations, despite efforts to address flood safety risks, said Susan Clift, the city’s director of engineering and public works.
Nanaimo city staff members have pitched a new plan to solve the short-term flood risks posed by the century-old middle and lower Colliery dams this winter. The strategy, outlined for councillors Monday, proposes the city rolls out water level monitoring, an evacuation information blitz and new neighbourhood sirens over the next seven weeks.
The multi-level plan is expected to cost $50,000 to $100,000 – adding to the $700,000 expense the City of Nanaimo has already incurred to determine the future of the Colliery dams.
And even with the latest precautions, Clift said the city will not meet provincial dam safety rules. The province has flagged the two dam structures for being at extreme risk of failing during a major quake or flood and has required the city to fix any public hazards in a timely manner. The provincial authority also expects a long-term solution for the structures this September – a document city staff members do not expect will be ready until after interim measures are in place this October.
The consequences for not following regulations is unclear according to Clift, but she said there’s little else the city can do except to move forward with its latest action plan.
The B.C. Dam Safety Branch has declined to comment until the city submits new short-term mitigation measures.
City council debated the recommended interim actions after press time Monday.
“[To be in compliance] we would have had to complete the plan that we had, which was to remove the dams,” Clift said. “We still need to go ahead and do what we can and when that’s in place, work expeditiously on a long-term plan.”
The City of Nanaimo and the B.C. Dam Safety Branch have been working toward a solution for the Colliery dams for close to 12 months.
When the city opted to halt demolition of the dams for a 30-day consultation with the Snuneymuxw First Nation, a spokesman for the province said he was concerned the delay would prevent the city from acting on its plan to remove the structures. The city was urged to quickly correct the dams’ problems, as well as come up with short-term measures to allay risk while deficiencies are being addressed.
But Nanaimo city officials are now only prepared to focus on interim solutions, pointing out there is no longer time this season to do physical changes to the dams.
The new plan looks at dam monitoring and sensing systems for water levels, information signs, emergency response exercises and a new neighbourhood siren system.
Toby Seward, the city’s general manager of community safety and development, said the plan is important for the safety of people this winter. The alarms – modeled after Tsunami warning systems – will ring if water reaches certain levels and new signs will help direct people on where they should go in an emergency.
If approved, the new system will be installed this fall and close to 1,800 Harewood residents will be invited to emergency drills.