Boaters on Mara Lake are being asked to be cautious as debris from the recent Cooke Creek flooding has made its way into the lake.
Islands of deadheads and other wood waste can currently be seen from the shores of Swansea Point, while a swath of the same runs along the shoreline. The wood waste is the result of the massive May 2 debris slide in Enderby that has since made its way along the Shuswap River and into Mara Lake.
On Tuesday, May 13, the Shuswap Emergency Program (SEP) issued a warning to boaters and other lake users of the potential hazard posed by the debris.
“Logs that are floating in the water have a low profile, and are very hard to see with a slight bit of chop. Boaters are urged to slow down and be aware of their surroundings, especially in inclement weather,” states the SEP release.
Debris from the Cooke Creek incident has had a visible impact on the colour of the water flowing from Mara Lake past the district’s water intake, and into the channel. This, however, has not had much, if any, impact on local turbidity readings, which over the past week have remained under 2 NTU (a boil water advisory is issued for anything between 0 and 5 NTU).
“We’re getting the surface discolouration with the different silt and that’s coming through, but so far it’s not affecting – to any great degree anyways – our water supply,” said district operations manager Randy Hand. “Earlier this week we were sort of expecting something to come out of it from what happened in Mabel Lake, and how it obviously makes its way through to us. We have all kinds of alarms and everything else for our water intakes, and we actually turned off the pumps while we weren’t here so we wouldn’t fill our reservoirs if there happened to be a sudden spike.”
Regardless, Hand says the water system is being closely monitored, and Interior Health is being made aware of everything that goes on.
Hand suspects the relatively stable turbidity levels are due in part to the Mara water system intake having been raised after the 2012 debris flows at Sicamous and Hummingbird creeks.
“They raised the intake because all the really heavy silts were going down and that’s what was being sucked up,” said Hand, noting the water quality advisory that has been in effect since 2012 remains in place.
“That will not change until we get a water treatment plant,” he said. “It will change for the worse, like an alert if the water quality drops. But we’ll will never come off that, that will be our minimum.”
With turbidity levels between one and five NTU, it is recommended water be boiled prior to consumption by children, the elderly and people with compromised immune systems.