Tubing enthusiasts looking to float down Nova Scotia's Gaspereau River have until Sunday to scratch it off their summer to-do list because after that, the season may be over.

Every year, people flock to the river to enjoy a casual float on the Gaspereau River, which is part of the Black River hydroelectric system. Water levels are regulated by a number of environmental permits.

Joy Power is owner and operator of Gaspereau River Tubing in Wolfville and says after Sunday, it's unlikely the water levels in the river will be high enough to enjoy the sport.

"It's been good so far and you take what you get," she said.

"We really never know if we're going to be open after June 15. It's all going to depend on the water level after that."

David Rodenhiser, spokesman with Nova Scotia Power says the utility has to keep the system running 24 hours a day until June 15 to allow for fish migration.

From Victoria Day to Labour Day, they are mandated to keep a certain water level on Black River Lake for summer cottages in the area.

"We've reached the point in the year where those two environmental requirements intersect," he said in an email to CBC News.

"We've drained a lot of water maintaining flows for fish migration, and now we've got to reduce the flows for a few weeks, because we have to keep the water levels up in Black River Lake for the cottages and bass."

How much water can flow through the Gaspereau River is regulated by a number of environmental permits. (www.novascotialocalfied.com)

Rodenhiser says many people blame NSP for slowing down the flow of the river to perform maintenance.

"The misunderstanding is understandable, because when the flows are slowed and we're not generating electricity, we do our annual inspection and maintenance work on the turbines and generators, and any other upgrades to dams and other infrastructure. It's a matter of trying to make the best use of the time."

'This is the best time of my life!'

Joy Power says it is disappointing the season will end so early, but that NSP does communicate with the owners of river tubing businesses.

"They can't give me a whole lot of notice after June 15, but they usually give me a week in advance or a few days," she said.

Five-year-old Ethan Sanchez from North Carolina was able to experience tubing the Gaspereau for the first time this week while visiting with his mother and sister.

"I said this on the second time on the river, I said, 'This is the best time of my life' and I'll never forget it."

Rodenhiser is optimistic the tubing season may not be over yet.

"By late August we should have enough water in Black River Lake that our permits will allow us to start flowing more water and generating power again," he said.

"So tubing will be able to resume for what's usually the hottest part of the summer."