A second pond leveller is no longer in the works for Coats Marsh Regional Park.
Parks reports have indicated for over a year that a second pond leveller would be installed to control water levels at the decades-old concrete weir. Now, instead, parks staff are manually siphoning water behind the beaver dam near the weir.
On Aug. 4, staff installed siphons at the regional park to draw down 40 centimetres of water in the wetland behind the beaver dam, according to RDN parks staff.
“While the beaver dam has been in existence for several years and has survived numerous winters with high water level events and is apparently stable, the RDN is exploring proactive measures to help moderate any potential flood risk associated with the beaver dam,” Mark Dobbs, superintendent of parks operations and capital projects, said.
Dobbs said the beaver dam has elevated the water level in the wetland behind the dam by 1.1 m above the outlet weir. Following the drawdown, which is being done through siphons installed by hand, a permanent siphon will be installed later this summer “to move water over the beaver dam, without any direct impact to the beavers or the dam, to help manage water levels at or close to the pre-existing outlet weir elevation.”
On the morning of Aug. 9, holes were discovered in the tubing causing the siphons to stop working, Amy Gore, superintendent of research & planning development, recreation and parks services, said. As of Aug. 13, the water level had been lowered by 11 cm. Madrone Environmental Services and the RDN planned to be back on site the week of Aug. 16 to reinstall the siphons and restart the drawdown.
Previous to the change of plans, RDN parks staff indicated a second pond leveller was needed to lower the water level and was one of the recommendations from a May 2020 weir assessment report, which has not been made available to the public.
Staff have previously told the Sounder that there have been no issues as a result of water buildup behind the dam since the RDN acquired the land in 2008.
Parks staff say the drawdown of water is occurring during a “low-risk window to avoid any potential impacts to native wildlife.”
The RDN did not respond to a question asking if the drought the region is experiencing has been a consideration with regard to the water drawdown.
Rachelle Stein-Wotten, Local Journalism Initiative Reporter, Gabriola Sounder