Military issues warning ahead of explosives training on B.C. island

A baleen whale breaches the water surface inside the two-kilometre radius of the Bentinck Island demolition range while a navy sentry boat tracks the whale’s position. (Royal Canadian Navy)

The Department of National Defence is warning boaters to avoid a small island southwest of Victoria this week as the military conducts routine, but potentially dangerous, demolition training.

The department says its land-based demolition range on Bentinck Island, near the Canadian Armed Forces ammunition depot at Rocky Point in Metchosin, will be in use daily from 8 a.m. to 4 p.m. on Oct. 1 to Oct. 4.

"Local residents will likely be unaware of the activities except on days when atmospheric conditions affect how far sound may travel," National Defence said in a statement Monday.

The department says the training is critical to ensure Canadian Armed Forces members can gain critical skills and maintain operational readiness.

The military says mitigation measures will be in place to limit the acoustic impact of the testing on marine mammals in the Strait of Juan de Fuca.

A third-party marine mammal observer will be on hand to advise military staff when the range is clear of whales and other mammals prior to demolitions, the department said.

"Events are delayed if whales are observed in or transiting towards the range, and activities do not re-commence until the marine mammal observer provides the all-clear," according to the statement.

The Department of National Defence increased its wildlife protection measures around the island in 2017 in response to complaints from whale-watching tour operators who were concerned the explosive blasts were harming orcas and migratory whales in the area.

In a meeting with the groups, the military agreed to halt detonations when marine mammals were spotted within two kilometres of the island, and limit the weight of explosives used in training from 2.25 kilograms to 1.13 kilograms.

From lighthouse to leper colony

The military has been detonating explosives at the Bentinck Island range since 1962.

The island was originally designated as a lighthouse reserve in 1860, but was later made redundant by the manned lighthouse station at nearby Race Rocks, according to the B.C. government's geographical names database.

Bentinck Island was later used as one of only two leprosy hospital colonies in Canada, replacing the former colony on D'Arcy Island in 1924, and featured 15 private cottages for patients and two larger facilities to house nurses and caretakers, according to the province.

The leprosy colony was closed in 1956 when the last patient died. A total of 13 patients are buried in the island's small cemetery, according to the province.

The waters around Bentinck Island are frequented by kayakers, recreational boaters and paddle boarders, but public access to the island is strictly prohibited by National Defence.

"The public is reminded that no unauthorized person may enter this area and trespassing is prohibited," the statement said.