HALIFAX -- Nova Scotia may be known as Canada's Ocean Playground, but the moniker hardly applies to Halifax harbour.

Almost 10 years after the city spent $333 million to clean up its massive, infamously polluted harbour, the two public beaches near its downtown remain strangely quiet -- even on hot, sunny days.

Despite monitoring that shows the crystal-clear saltwater is fit to swim in, the city decided this year not to post lifeguards at the Black Rock and Dingle beaches, saying there were so few swimmers last year it didn't make sense to hire rescuers.

"There hasn't been an appetite for swimming," says city spokesman Nick Ritcey.

Anika Riopel, a 28-year-old student of environmental sustainability at Dalhousie University, says the problem is that Haligonians won't let go of their ugly memories of what the harbour used to be like.

Local residents and businesses dumped raw sewage into the harbour for more than 250 years.

Before three wastewater treatment plants started operating in 2008, the harbour was continually fouled by 180 million litres of sewage every day. That's enough to fill 72 Olympic-size swimming pools, topped with an icky assortment of brown "floatables," condoms and tampon applicators.

"We spent millions cleaning up our harbour and the data now show the harbour is clean, but the perception continues to be what the harbour was 10 years ago," says Riopel.

"This is not just about swimming. It's about changing our relationship with the harbour."

Haligonians do love to swim -- the city is dotted with popular lake beaches that offer warmer, if sometimes cloudier, waters than the harbour.

Riopel has a bold vision for what the harbour could look like for swimmers. She started a campaign three weeks ago simply called "Jump In."

Her plan is to get the city to cordon off a small section of the downtown waterfront to create an urban swimming hole, complete with diving platform, raft and, of course, lifeguards.

Having travelled extensively before arriving to study in Halifax in 2014, Riopel said she was inspired by similar projects in other port cities, including the Taranaki Street Wharf jump platform in Wellington, New Zealand.

Riopel's campaign has so far included a cheeky YouTube Video that shows her and a friend jumping into the harbour from a wooden wharf.

"It was refreshing," she said, referring to the 17 C water.

"The more people see others going into the water and not getting sick, the more outdated the original perception is going to become," says Riopel, who is originally from Sault Ste. Marie, Ont.

"(But) memory is stronger than our own senses sometimes ... Our perceptions are sometimes stronger than facts."

Later this week, she plans to set up a tent near the proposed swimming area, where she will seek public input. She has architectural drawings to illustrate what the swim site might look like.

Deborah Page, spokeswoman for the provincial waterfront development agency, says the Crown corporation is excited by the plan.

"The more opportunity you can give people to interact with the water, the better their overall experience is," she said. "It can be a huge draw."

However, Page said the agency must first consult with waterfront businesses, the port authority, the harbour pilotage authority and the municipal transit system, which operates a ferry service that links downtown Halifax with neighbouring Dartmouth.

"We don't want any issues with boating traffic, and we want to make sure there aren't any hazards under the water," Page said.

At 12.3 square kilometres, Halifax harbour is one of the deepest and largest natural harbours in the world. And its high environmental standards have won it special designation as a so-call blue flag marina, the first such designation in Atlantic Canada.

A water quality monitoring report prepared by AMEC Earth and Environmental in April 2011 showed fecal coliform levels were well below applicable guidelines in all areas of the harbour. In particular, levels in the inner harbour -- once the most polluted area -- had fallen by 97 per cent when compared with samples taken as late as 2007.

Still, the city's Harbour Solutions project went off the rails in 2009 when a power outage at the Halifax treatment plant led to catastrophic flooding inside the building. It remained offline for at least seven months, and the harbour soon became the putrid, green-brown mess everyone remembered.

Riopel admits that was a serious setback, but she is quick to note the water has remained clean since 2010.

Her group's Facebook page includes many encouraging comments, but it's clear many doubters remain.

"I think there is still a lot of public concern about the harbour water quality," says one message. "Deal with this bad PR and this could be a cool project to see come to life!"