High water levels on the St. Lawrence River are slowing down the start of boating season and damaging tourism businesses in the Thousand Islands region.

On Tuesday, the Township of Frontenac Islands declared a state of emergency and began distributing sandbags. The Frontenac Islands are approximately 215 kilometres southwest of Ottawa.

Nearly 1,000 sandbags and six pumps weren't enough to keep out water out of the basement of the Boathouse Country Inn and Restaurant in Rockport, Ont.

The worst may be yet to come.

We're at our limit now with sandbags and what we're able to do with pumping water out of the basement. -Kathleen Allen, Rockport Boatlines and Boathouse Country Inn & Restaurant

"We're hearing that the water level isn't going to start going down for at least another several weeks," said general manager Kathleen Allen.

Allen said the restaurant is running its pumps 24 hours a day and has teams reinforcing sandbag walls as the river swells.

Basement flooding Boathouse Country Inn in Rockport May 18, 2017

Pumps are running 24 hours a day at the Bouthouse Country Inn & Restaurant in Rockport. The general manager said the restaurant bought six additional pumps to deal with historically high water levels. (CBC)

"That's a bit daunting. We're at our limit now with sandbags and what we're able to do with pumping water out of the basement. So I'm not sure where we're going to go from here."

Allen also manages Rockport Boatlines, which had to cancel its popular Boldt Castle cruises to Heart Island because the docks are under water. The cancellation has affected 400 tourists who had already bought tickets, Allen said.

Flooded docks delay boating season

The high waters have also led to a delay in the season at Ed Huck Marine in Rockport, according to co-owner Scott MacCrimmon.

"We've never seen the water levels so high," he said. Some people who bought boats from the business have put off delivery because their cottage docks are under water, MacCrimmon said.

Scott MacCrimmon, co-owner Ed Huck Marine in Rockport May 18, 2017

Scott MacCrimmon is the co-owner of Ed Huck Marine in Rockport, which has experienced some flooding and a loss of business due to rising waters on the St. Lawrence River. (Judy Trinh/CBC)

The Victoria Day weekend is traditionally the start of boating season, said MacCrimmon, but this year only two-thirds of the marina has launched and their fixed docks and the gas dock remain under water.

He warned boaters to be careful about creating excessive wakes on the water.

"River traffic needs to be super-conscious about their wake," he said. "In the summer that's an annoyance and it will rock people's boats at their docks. This time of year, you're putting water right over their seawalls and encroaching on their property."

Large debris a problem

The high water has also brought with it unusually large debris.

"Right now, we're seeing much larger objects," MacCrimmon said. "We're seeing people's floating docks that have broken free, we're seeing entire tree limbs and so on in the water."

Fisheries and Oceans Canada data shows the water level of the St. Lawrence in Kingston, close to the Township of Frontenac Islands, has increased from 1.3 metres on May 1 to 1.6 metres on Thursday.

The river usually peaks in mid-June.

frontenac islands map

The Township of Frontenac Islands activated its emergency response plan on Tuesday, May 16. (Google maps)

with files from Judy Trinh