Canoers and kayakers competing on Lake Banook in Dartmouth, N.S., are going up against more than just other competitors these days because of a weed problem which is creating havoc on the water.

The weeds float near the surface of the water, break free from the bottom and form weed islands. Organizers say the weeds have been plaguing the paddling lanes for the past five years.

About 10 to 15 times a year, the Atlantic Division of Canoe Kayak Canada rakes up the weeds along the lanes, especially the area where the longer races start.

In total, the raking efforts are bringing in about a half tonne of weeds during each raking session.

Chris Chaisson

Chris Chaisson says it's not fair for paddlers to have to have their hard work ruined by some rogue weeds. (CBC)

The city has held meetings about long-term solutions to the problem on both Lake Banook and Lake Micmac. City council says it's waiting for a report before making a decision about how to deal with the weeds.

“It needs to be settled permanently,” said Chris Chaisson, the head coach at the Mic Mac Amateur Aquatic Club.

He says the qualifications for national championships were held at Lake Banook recently and there were complications.

“Every single club had at least a few issues with weeds and it’s difficult when you’re trying to qualify for an important event like that and you get kids that miss their qualification simply because they hit a patch of weeds,” he said. “It’s not fair for the kids.”

The weeds even temporarily shut down the motor of the boat that took a CBC reporter out on Lake Banook while doing research for the story.

Three possible solutions

The city says there are three options for dealing with the weed problem. The most expensive option is to dig up and remove the sediment, a process that would cost about $1 million a year.

The city could also chop plants with an aquatic lawnmower-like machine. The device costs between $100,000 and $300,000, and the city would spend another $20,000 a year to operate it. Contracting out the work would cost about $180,000 a year.

The least expensive option is to use an aquatic herbicide to the kill the weeds. It would cost about $119,000 per year.