Coming to beneath a park and school near you: a hydro substation?

BC Hydro says it must replace three aging Vancouver substations to meet the city's future power needs. The plan, which its CEO described as a "big new idea," is to build new stations underground, beneath two parks and a school.

The utility pitched the plan because land — above ground — in downtown Vancouver is pricey and hard to find.

Rather than launch a search for two large lots, it came up with the plan to build the new hydro substations underground.

"We suddenly realized you can flip the question around," said BC Hydro CEO Jessica McDonald.

"We saw ourselves staring at this great big idea and wondered why we hadn't had it sooner."

The underground substations would be constructed beneath Emery Barnes Park in Yaletown and below Lord Roberts School Annex in the West End.

The utility had been searching for sites to build new substations when it landed on the idea to go underground.

It's not the first time Vancouver has built an underground substation. Right now, there's one beneath Cathedral Square in the city's downtown, the first underground hydro substation in North America.

There are two other above-ground substations; the Murrin station on Main Street and the Dal Grauer substation on Burrard Street near Nelson Street.

Stations aging out

The city's power needs are expected to grow by 75 per cent over the next few decades and these power stations are nearing the end of their lifespans, McDonald said.

The proposed hydro plan would also expand the substation below Cathedral Square park.

McDonald said the underground plan will benefit the city. Instead of spending millions on expensive downtown land, the utility will agree to pay to upgrade city parks and build schools and daycare spaces.

The Vancouver Park Board will vote on the plan in March. Before that, BC Hydro will seek public input on the plan.

Park board chair Michael Wiebe said the benefits to residents, including park upgrades and cash, worth "10s of millions of dollars" must be considered.

"Its a big decision for the park board," Wiebe said.

A spokesman for the Vancouver School Board said it's concerned about the safety of students but will wait to hear more information at public input sessions.

Poses safety concerns

McDonald said proposed underground substations are safe. Right now, there are 37 hydro substations in the Metro Vancouver area, half of which are located within 100 to 200 metres of a school, park, community centre of high-use area, she said.

Hydro substations, and electric equipment in general, create electric and magnetic fields, which can pose a health risk in high doses.

Electric and magnetic fields are measured in milligauss (mG). According to the World Health Organization and Health Canada, the safety threshold is 2,000 miligauss, McDonald said.

The physical area on top of Cathedral Square park has an electric and magnetic field measurement of 30 miligauss, she said, which is about the same as standing next to a washing machine and 10 times less than using a vacuum cleaner.

According to Health Canada, the International Agency for Research on Cancer (IARC) has classified extremely low frequency electric and magnetic fields as "possibly carcinogenic to humans."

However, the "vast majority of scientific research to date does not support a link between exposure and human cancers," Health Canada's website says.