Rock removal could alleviate flooding at Sproat Lake, citizen group says

Rock removal could alleviate flooding at Sproat Lake, citizen group says

Alberni-Clayoquot Regional District looking for provincial assistance on conducting hydrology study

Members from the Sproat Lake Community Association (SLCA) are asking for provincial assistance to conduct a hydrology study to ultimately remove a bedrock outcrop on the left bank of the Sproat River.

The rock, located immediately downstream of the lake outlet, was identified in 1992 as a hydraulic constriction during floods in the Sproat system, and is believed to have contributed to high flood levels in Sproat Lake, according to a proposal for an engineering hydrotechnical study by Northwest Hydraulic Consultants (NHC).

“Bob Cole (SLCA) and a group of people have looked at the flows from the Sproat River flowing out of the lake and determined that there is a large rock that restricts flows during the high flow periods,” said Russel Dyson, Alberni-Clayoquot Regional District CEO, at a March 15 board meeting. “Removing this rock, they feel would get the water out of Sproat Lake faster and alleviate some of the flooding.”

Cole contacted the hydraulic consultants in February to discuss flooding of Lakeshore residents that occurred in the fall of 2016, as well as past major floods. These floods have affected dozens of homes and properties in the Alberni Valley with damages in the hundreds of thousands of dollars, according to NHC.

“The flooding affects Sproat Lake, Beaver Creek, the city, Tseshaht and Hupacasath and that’s just the immediate people,” said Penny Cote, ACRD Sproat Lake director. “I agree that a study needs to be conducted before anything is done. I don’t support just going in there and blasting the rock out, but I do support getting assistance from the province from either emergency planning or ministry of environment.”

John Jack, ACRD board chair, said he would begin consultations with First Nations representatives that are affected by Sproat Lake flooding regarding the possible rock removal and study.

Dyson said the removal of the rock is relatively simple and experts have already estimated schedule and costs.

According to NHC, the project is expected to take 12 weeks to complete and the cost estimate for the work is $40,000 plus GST.

Where funding would come from for the project has not been determined yet.

“But what is not simple, is potential impacts to the down stream,” Dyson said. “Sproat Lake is like a sponge, it’s a tremendously large watershed. It’s also very complex because it flows ultimately into the Somass which is fed by Great Central Lake and Elsie Lake. We have witnessed impacts to downstream residents both in Beaver Creek along Ferguson Road and Tseshaht.”

The ACRD board has written a letter to Minister of State for Emergency Preparedness Naomi Yamamoto asking that she spearhead, or ask the relevant ministries from federal and provincial governments to take a look at the watersheds and what can be done.

A motion was made to write additional letters to appropriate provincial government representatives on the matter of the rock removal.

“Something needs to be done, I think there’s several options and the province needs to be the spearhead to get it done and get it done right,” said John McNabb, ACRD director for Beaver Creek.