Flooding continues for a second week along Lake Ontario and the St. Lawrence Seaway and there’s no end in sight. Many lake residents - and New York’s Gov. Andrew Cuomo - want more water released downstream, through the huge Moses-Saunders Dam that holds water back for the St. Lawrence Seaway. But it’s not that simple.

Tom Piekunka stands in an inch of water in his backyard in Sodus Point, N.Y. Water from Lake Ontario is still on the rise, and it's creeping closer and closer to the bright yellow two-story cottage where his family has lived for generations.

"If this was just a house I wouldn't care," he says. "But, it's a home."

Piekunka says this is the highest he's ever seen the water, and he’s blaming the International Joint Commission, the U.S.-Canadian body that helps to oversee the Great Lakes. This year, it changed the way water levels on Lake Ontario are regulated.

Piekunka says he's particularly upset because he believes all this flooding was avoidable. "It's the government that's doing this."

Piekunka isn't the only one pointing the finger at the IJC and its new plan for Lake Ontario. Residents and elected officials along the lake shore have been calling for the plan to be scrapped.

At the center of this debate is the Moses-Saunders Power Dam — a mammoth concrete structure that stretches over half a mile across the St. Lawrence River from upstate New York to Ontario, Canada.

It was built in the 1950s, not just to generate power, but also to control two powerful bodies of water. The water flows east from the Great Lakes toward the Atlantic Ocean. And all that water – from a lake system far bigger than New England — passes through the dam.

Jacob Bruxer helps manage it. He's a water resources engineer with the Canadian government, and his job is to calculate how high the lake is and how high the river is. He uses that information to advise the board that decides how much water passes through the dam.

But figuring out how much water is in one of the largest lakes in the world can be tricky. Bruxer and his colleagues have to consider rainfall, runoff, ice melt, water coming in from tributaries, and even the rate of evaporation.

These are the same variables every hydrologist considers, he says. "It's just, this is on a much bigger scale with the Great Lakes."

The water on both Lake Ontario and the lower St. Lawrence reached record highs this season, but Bruxer says that is not because of changes to the regulation plan.

What has changed, he says, "is that we've had an exceptionally wet month of April. Then, the start of May here has been exceptionally wet as well."

Because both the lake and the river were swollen with rain, it has been hard to provide relief to one area without damaging another. Hold too much water above the dam and homes along Lake Ontario shoreline get flooded. But downstream in Montreal, they’re dealing with flooding problems of their own.

David Speak is the general manager of Beaconsfield Yacht Club on a portion of the St. Lawrence near Montreal called Lake Saint Louis. He’s been stacking sandbags along the shore because the water is already two feet higher than he is used to.

Speak says releasing more water from the dam would be a disaster. “If they open up dramatically there, then we all end up swamped, millions of people down here in this part of the system.

"There’s no happy solution.”

While this flooding coincided with the new lake management plan, Bruxer says there's nothing the board would have done differently if this had happened last year, under the old plan. In the meantime, the IJC is still working to minimize flooding both upstream and downstream and hoping for dryer weather.

Video: Why does it take so long to lower the level of Lake Ontario?

Great Lakes Today is a collaboration of WBFO Buffalo, ideastream Cleveland and WXXI Rochester