Lake Simcoe Watershed suffers from winter salt pollution (yorkregion.com)

Salt goes wherever water goes, and in northern York Region more and more winter salt has slipped invisibly into rivers such as the East Holland, local groundwater and Lake Simcoe.

“Once it’s in the environment, you can’t get it out,” Bill Thompson, Lake Simcoe Region Conservation Authority’s watershed planning manager, said last month.

The authority knows waterways around the lake have absorbed steadily increasing amounts of salt since the 1970s. Its watershed report card last year said LSRCA is working with municipalities and industry to scale back salt use, but admits “climate change, urban expansion, and increasing public expectation (on winter safety) are making reductions difficult to achieve.”

Thompson puts part of the blame on private contractors who may not understand how much salt is really needed to keep a sidewalk or parking lot safe.

“The only thing we as a society can do is use less salt,” he said.

Claire Malcolmson, executive director of the Rescue Lake Simcoe Coalition, wants stronger measures on salt before it’s too late.

The LSRCA in 2015 identified “salt vulnerable areas” in the lake’s watershed, reporting most samples collected from Tannery Creek, Lovers Creek, the East Holland River, North Schomberg River, and Hotchkiss Creek exceeded the federal guideline for long-term exposure.

Claire Malcolmson of Rescue Lake Simcoe Coalition says salt pollution continues to rise in Lake Simcoe's watershed and will harm aquatic species unless curbed. Expanding the road network — building the Bradford Bypass, for example — makes it harder to reduce salt pollution, she says.

Claire Malcolmson photo

The authority’s report projected, based on the watershed’s estimated population growth, that salt would affect 45 or 47 studied aquatic species by 2031, a prediction Malcolmson called “devastating.”

Queensville contains headwaters of the Maskinonge River, which has low flows and relatively little ability to dilute salt applied to the area’s roads and parking lots, the report added.

“The effect is already there. No one is explaining how we’re going to bend that curve,” said Malcolmson, whose group recently sparked a provincewide campaign, the Ontario Salt Pollution Coalition.

Chloride hot spots tend to be in urban areas and along major roads. The Bradford Bypass, a proposed eight-lane highway crossing the East Holland watershed, would only worsen salt pollution, Malcolmson and other conservationists say.

Since Highway 404 opened north of Green Lane, 84 per cent of water samples taken from the Maskinonge River have exceeded chronic salt levels, Malcolmson and Bill Foster of Forbid Roads Over Green Spaces wrote to an Environment Canada official last year.

What will Environment Canada do to protect the West and East Holland Rivers, which flow into Lake Simcoe, from salt pollution that “will dramatically increase” once the bypass is built, they asked.

“Either we deal with the salt problem as it is now,” Malcolmson and Foster told the official, “or we deal with this again in a decade when it is much worse.”

Malcolmson said her group and the provincewide coalition are optimistic the provincial government will take action on salt — Environment Minister Andrea Khanjin and Attorney General Doug Downey, after all, represent Lake Simcoe Watershed ridings — which follows the advice of scientists and target reductions.

LSRCA continues to monitor water quality and educate municipalities to make better decisions on salt.

In this, Newmarket is one of the watershed’s biggest successes. The town uses Thawrox, a treated salt that can melt ice at a lower temperature than regular road salt.

The town once used 110 to 140 tonnes of salt during each snow event, but introducing Thawrox in the winter of 2017-18, has dropped use to between 55 and 70 tonnes — a 50 per cent reduction, said Peter Noehammer, Newmarket’s development and infrastructure commissioner.

The town checks and monitors salting equipment and uses electronically controlled spreader devices to ensure correct salt application, and continuously trains and educates snow operators on salt application rates and plowing procedures, Noehammer added in an emailed response to questions.