For more than 50 years, the dam on the St. Lawrence River at Massena has determined the water levels in Lake Ontario, with its primary mission to protect shoreline property from damage and erosion.
Now the international commission that regulates the lake is weighing changes in the water levels to ease concerns about the current policy's effect on shoreline ecosystems.
That is putting environmentalists and many shoreline property owners at odds.
Since the late 1950s, the high and low levels of the lake, set by joint U.S.-Canadian policy, have always within a 4-foot range -- highest in late spring and lowest around the end of the year. The mean level of the lake is 245 feet above sea level.
The bi-national International Joint Commission that controls the lake levels is looking to change the policy, allowing high levels to climb a little higher, and low levels to drop a little lower. That would be closer to the "natural" level changes in the lake, before the dam was built.
A change of even a few inches on either end of the range has major effects, say shoreline property owners, boaters, anglers and environmentalists. Depending on their point of view, they see great promise, or grave threats, in altering the lake policy.
The joint commission held 10 hearings around Lake Ontario and the St. Lawrence River this year. More than 150 people attended the final hearing in June in Oswego. Participants came from Onondaga, Oswego, Cayuga, Jefferson and Wayne counties.
Most who spoke, representing the view of property owners, called on the board to keep the current policy. Higher water levels, they say, would wreck their seawalls, swamp their decks and, when winds drive waves higher, destroy their summer homes.
But others, from a coalition of environmental groups, called on the board to adopt a new plan to reverse the loss of wetlands and wildlife that they said resulted from 50 years of "unnatural" lake levels. The once healthy swamps that helped clean the lake and buffer rain and snowmelt, have shrunk, they said, pushing some animals onto the endangered list.
The commission plans to reach a final decision by the end of the year.
The Shoreline Debate: How to regulate Lake Ontario water levels
Before the end of the year, the International Joint Commission that regulates Lake Ontario is expected to decide whether to change the lake's water levels, making the high level higher and the low lower. Generally, shoreline property owners oppose a change; environmentalists support it. Here's a look at various points of view on the issue:
Higher Lake Ontario water levels would destroy seawalls, flood septic systems and wash away some camps, or even year-round homes, said Kim Park, supervisor of the lakeside town of Wolcott in Wayne County.
"You're going to have erosion with higher highs (higher lake levels) for longer periods of time," she said.
She and dozens of Wayne County residents showed up at a hearing on Lake Ontario water levels to make it clear that higher water levels are a serious threat to their community.
Higher water would flood docks, lakeshore residents said, and make boat launches unusable and wreck business for marinas and charter fishermen. It would lower property values of waterfront property owners.
Lower sales tax revenues and falling property taxes would damage Wayne County, Park said. "This is a poor county," she says, sitting on her family's boat at a marina in Port Bay.
Lower water levels, which the plan would also allow, would be a problem too, she says. The intake for the local water system is just a dozen feet offshore. It is already troubled by seaweed when the water drops in the fall. Lower levels would leave it high and dry and create a "homeland security issue," because the intake would be visible.
For those on well water, lowering the lake a foot would lower water tables as well, Park said.
"We have been dealing with highs and lows in the four-foot-range for 50 years," she said, "that's what we built all these structures on."
Altering that doesn't make sense, she said, until she hears something she hasn't heard: "a real good reason - or scientific reason - as to why we need to change."
Sally Sessler remembers the sand dune that was behind her parents' camp and the sandy beach that was in front of it back in 1947.
The beach is gone now and the dune is a fraction of what it used to be. The cottage is gone. Sessler and her husband tore it down when they built a new cottage farther from the relentlessly pounding waves of Lake Ontario.
Sessler and neighbor Sally Oliver don't want the International Joint Commission to adopt a new plan if it means higher water levels. They have seen a beach broad enough for games of volleyball disappear beneath the waves, seen dunes scoured to nothing by wind and water and seen North Rainbow Shores Beach - the spit of land between the lake and South Sandy Pond where they spend their summers -- reduced to a width of less than 100 feet at some points.
Both remember the destruction that came with Hurricane Agnes in 1972 and worry higher lake levels will have the same effect as the storm.
They and other property owners have installed rocks and boulders - called riprap - to help protect their shoreline and they've planted dune-protecting beach grasses as well. "We put in $10,000 worth of rocks 10 years ago," Oliver said.
They've experimented with ivies, other plants and grass clippings to try to keep what remains of the dunes from shrinking further.
But the lake is relentless. Those rocks Oliver installed, "it just pulls them back down."
Oliver and Sessler would like to see lower water levels at times.
Low levels, they say, expose the sand at the bottom of Lake Ontario to the wind. The sand gets blown onto land, rebuilding the dunes and beach.
"It would make sense just to leave it low," Sessler said. "We'd like it lower."
Lower levels last fall created a beach about 10-foot wide, the two women said. But when water levels increased this spring, that 10-foot beach, like the wide sandy beaches of the 1950s and '60s, disappeared.
Once there were thousands of black terns along the shores of Lake Ontario, said Gerry Smith, president of the Onondaga Audubon Society.
They lived and nested among the different types of wetlands -- "a mosaic," he calls it -- that was a natural feature of the area. But that mosaic is nearly gone, replaced by "a monoculture," where cattails five- and six-feet high dominate area swamps.
There's no place for black terns or Virginia rails. Smith said that's because 50 years of regulated water levels have prevented the flooding necessary to drown out some cattails and allow water access for muskrats, which have a voracious appetite for cattails.
Water levels have also not dropped low enough to encourage the marsh meadows, where open water and plants form the mosaic that leads to greater plant and animal diversity.
"A healthy natural world fluctuates," Smith says, standing next to a wall of cattails at Sage Creek Swamp in Mexico.
"That's not a healthy wetland," he says, pointing to the swamp. "We haven't seen a black tern nest here for 10 to 15 years."
"We are essentially stewards of the planet," he says. "Keeping a healthy population of other species are important to a healthy ecology."
Smith wants to see the International Joint Commission move toward the plan called B-plus, which allows the biggest range of water levels.
He dismisses the alternative Plan 2007 as "a political animal," that is closer to the current 4-foot range than is needed.
And he has no patience for those who want to keep the existing policy because it is better for their waterfront real estate.
The high water levels about which landowners expressed so much concern will only come five times in a century, he said.
Noting that most of those who attended the hearing were, "baby boomers and up" Smith says: "If they are around for one of the highs, they certainly won't be around for two."
This year marks first time in five decades a new plan has been proposed for regulating water levels in Lake Ontario, and Dereth Glance and her organization want things to change.
"This is historic," said Glance, executive program director of Citizens Campaign for the Environment in Syracuse.
"Lake Ontario is one of the largest bodies of fresh water in the world," she said. "It's a very large freshwater ecosystem."
But it's one that is under near-constant attack from invasive species that include the goby and the now-ubiquitous zebra mussel.
The difference between the proposed new plans is just a few inches she said, but they make a difference. "It adds seasonality back."
That will "give native species a better chance of fighting introduced species," Glance said.
It will improve the area economy by encouraging tourism, fishing, recreational boating and bird watching, she said.
Citizens Campaign for the Environment, with 80,000 members, gathered 5,000 signatures on petitions in support of a plan called B-plus, which would increase the seasonal variation in lake water levels, Glance says.
The group is willing to compromise on timing for implementing B-plus -- perhaps as long as two years -- but wants "a date certain" when the "more natural" water levels will be implemented.
In the meantime, Glance said she would like to see waterfront landowners get some help dealing with higher water levels.
"An interim shoreline protection plan," she said, "with an educational component on ways to use natural plants and kinds of care."
Scientists have studied the matter, the public has spoken and officials are focused, so now is the time to act, she said, "so all this work, all of this knowledge is able to be put to good use."