On July 8, the Bowen Island Municipality received a letter from Vancouver Coastal Health stating that the Cove Bay water system is inadequate to address the issue of protozoan contamination. The letter, signed by Medical Officer of Health Mark Lysyshyn and dated June 6, requests that plans for a new treatment process meet a series of standards and states that such a plan will be placed as a condition to Cove Bay’s operating permit and will need to be in place before the current system is expanded. This is the first official communication the municipality has heard on the issue from Vancouver Coastal Health.
“We’ve heard grumblings from them which have come in increasingly strong language over the past five to seven years, and people who work in the water business on Bowen have been expecting something like this for a long time. Now the penny has dropped,” says councillor Andrew Stone.
Stone worked as a water operator on six water systems on Bowen Island between 2004 and 2010. He says that the requirements listed in the Vancouver Coastal Health letter essentially ask for: ozone treatment, uv treatment and the reducing the cloudiness of the water.
For the third requirement, the letter states, “for less than 1 NTU of Turbidity.”
Stone says that Cove Bay water hovers close to 1 NTU of turbidity which is an acceptable level of turbidity in water systems across Canada. On parts of the Island where people are drawing their water from deep wells, that level can be as low as 0.1, and it would appear very clear.
“Filtering the water to improve the clarity is in part solving an aesthetic problem,” says Stone, “but it is also important because chorine byproducts are associated with dissolved organics in the water and removing it will also help to make UV treatment more effective.”
He says the further away the water is from it source, the more dissolved organics will be in it.
“An eight-inch pipe goes out of Grafton Lake for the whole Cove Bay system, and when that system is running at full tilt, that means 1,000 gallons are being sucked out of there every minute,” says Stone. “The force of that suction means that a lot of sediment from the lake is getting pulled in along with the water.”
Stone says that filtering out the sediment will be the costly part of treating Cove Bay’s water.
“There are a few options,” he says. “You can use sand filters, which require a large amount of space – you’d need a few of them and they are the size of half a football field each. Coagulation is an option, but this process leaves behind a sludge residue and you have to find a way and a place to dispose of this. It would also make the site of the plant an issue, because you would not want to have sludge ponds at sitting right below Artisan Square.”
Stone also points to membrane technology used to filter out sediment, which has been used effectively to filter out the turbid water the city of Kamloops gets out of the Thompson River since 2004.
“This has proven very effective,” says Stone, “but it is very expensive.”
The cost of building the Kamloops water treatment totaled $48.5 million.
Reducing the turbidity of the water is necessary to make other forms of treatment, UV in particular, effective.
Stone adds that while the costs associated with building a water treatment plant on Bowen may seem prohibitive, Cove Bay water users have enjoyed low rates for years in comparison to other parts of the island.
“With 600 users, the Cove Bay Water System benefits from an economy of scale. Bowen Bay, by comparison, has 50 users,” says Stone. “And Cove Bay has also managed to avoid improvements to the standards for treatment. Hood Point had to get a filtration system in more than 10 years ago, and to do that they required a levy of $10,000 per household.”
Councillor Cro Lucas, the liason to the municipal infrastructure committee, says that while draft plans for a water treatment plant have already been drawn up, movement on the project is being held up by delays in the dispersal of federal-provincial infrastructure grant funds.
“When the details of where that money is going to be directed get sorted out, we will actually be able to start working on a grant application – and I expect that the letter from Vancouver Coastal Health will actually be of assistance to us in that process,” says Lucas, adding that the other hurdle to getting the water treatment plant built will be getting enough official support from Cove Bay water users to legally borrow the additional monies to pay for its construction.
