Plea made to modify lake’s rule curve

Several members of the public made a plea last Thursday night to modify the rule curve for Rainy Lake to keep water lower in the spring in order to avoid flooding later on in the year.
“For five years we’ve had the new rule curve and Rainy Lake has had high water for three,” Randy Pozniak, with the Border Lakes Association, said during the joint annual public meeting of the International Rainy Lake Board of Control and the International Rainy River Water Pollution Board, which took place at Rainy River Community College over in International Falls.
He added before the rule curve change in 2000, there only had been three high-water events in the past 30 years (1974, 1985, and 1996).
He suggested the rule curve be changed so that in April, May, and June, the water levels are low (within 50 percent of the rule curve operating band) in anticipation of heavy rains.
Pozniak also suggested to the room packed with more than 40 people, as well as representatives with the IRLCB, IRRWPB, and International Joint Commission, that a high water line be put in place so that water would be held back in the Namakan reservoir automatically when the level reaches that line.
This would limit the flow into Rainy Lake when the water levels already are in danger of getting too high and allow for more time to get the levels on Rainy Lake back under control (e.g., by opening dam gates).
Area resident Bob Hilke agreed something had to be changed given the modified rule curve has resulted in too many high water situations on Rainy Lake over the past five years.
In particular, he complained that with the higher curve, the dam here isn’t fully opened until the water reaches a certain level—a level which is higher than it used to be prior to 2000.
In a situation when heavy rainfall occurs, like this past May, and the water level exceeds the upper limit of the rule curve, the gates are then opened. But by then, it’s not possible to alleviate the high water situation fast enough, said Hilke.
“When you don’t open the gates until we’re well over the curve, that’s wrong,” argued Hilke. “Don’t wait until it’s a problem.
“This year, if we’d had a lot of rain, there would have been terrible damage and there’d be nothing we could do about it,” he added.
“We need to start off in the spring lower,” agreed another area resident, Carol Schumacher. “You know the rains are going to come.”
Yet another resident, Ed Hanson, said living on Rainy Lake “hasn’t been worth a darn for five years” since the rule curve changed.
“I’m not sure what the answer is. The board has to figure out something,” he remarked. “Maybe the Native Americans named them Rainy Lake and Rainy River for a reason. But an inch and-a-half [of rain] shouldn’t make a big difference.”
But Ed Eaton, U.S. engineering advisor for the IRLBC, stated the change in the curve in 2000 wasn’t drastic. And even if the previous rule curve still was in effect, people still would be seeing high water levels.
“It’s easy to blame some relatively small events on a change to the rule curve,” he noted.
But Eaton stressed the area has seen some unusual weather in the past five years that could never have been anticipated. For instance, in 2002, Rainy Lake saw the second-highest input flow ever in its recorded history.
“In cases like these, no matter what the rule curve is, it’s not going to matter,” said Eaton.
He added many people living in the Rainy Lake area have never witnessed serious flooding, such as that seen in Grand Forks in 1997, and may tend to overreact to what, in fact, are small changes to the lake levels.
“You never know what’s going to come,” said Rick Walden, Canadian engineering advisor for the IRLBC, referring to the fact precipitation can’t be predicted from year-to-year.
“If the idea was to operate the lakes for flood prevention, they would be operated differently,” he added, noting the change to the rule curve in 2000 was done after considerable public input—and the end result has been a matter of balancing environmental, commercial, and residential concerns.
“It’s a case of not being able to satisfy all the groups all the time,” said Walden.
Indeed, several members of the public on hand Thursday night said they felt the 2000 rule curve change “works well,” and felt the “water problems here are minor” compared to many other parts of the United States and Canada.
Eaton also noted the two mills in Fort Frances and International Falls—owned by Abitibi-Consolidated Inc. and Boise Cascade LLC, respectively—should be applauded for doing “a fine job managing the lake levels.”
In giving a brief overview of the water level situation here this past spring, Eaton said the period of time from the end of April into early May actually was “abnormally dry” until “a series of rainfall events” which started May 10 and continued for two weeks.
This resulted in the water level being above the upper limit of the rule curve on Rainy Lake for 41 days (from May 26-July 4). At one point, on June 8, it peaked at 11 inches above the rule curve.
This was the 27th-highest it’s been in the past 94 years such levels have been recorded.
As a result, the gates at the dam here were open from May 31-June 23.
The level currently is several inches below the upper limit of the rule curve.
In other business at last Thursday night’s meeting, Bill Darby, a local rep on the International Rainy River Water Pollution Board and district manager for the Ministry of Natural Resources, said the IRRWPB has put together a report regarding “hydro power peaking.”
This is the practice of mills using dam-generated electricity during the day, and public power at night when the rates are cheaper. This involves a fluctuation in water flow through the dam from day to night which may affect aquatic wildlife.
The IRRWPB came to the conclusion that the companies should not be “peaking” during the spawning period, and have sent letters to the two mills recommending such.
Darby added the board is continuing to look at hydro power peaking as it has received additional information on the issue from the Minnesota District Natural Resources.
A second meeting of the IRLBC and IRRWPB was held Friday morning at the Kay-Nah-Chi-Wah-Nung Visitors Centre near Stratton.
For more info on the IRLBC, IRRWPB, and IJC, visit www.ijc.org

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