Saturday, July 4, 2015

Level reaches dam overflow spillway

The level of Rainy Lake continues to rise as a result of June rainfall far in excess of normal across the drainage basin.

As such, the level of the upper Rainy River has risen close to elevation of the overflow spillway in the centre of the dam at Fort Frances/International Falls.
This spillway is designed to safely pass additional flow during high water levels.
The rate of flow over the spillway will increase gradually as the lake level rises.
Rainy Lake is forecast to rise roughly 10-15 cm (four-six inches) over the next seven days.
Meteorological forecasts suggest the possibility of more rainfall in six-seven days, which could have the lake rising again given the saturated conditions.
If dry weather continues, however, the peak level is projected at 338.75-338.80 m (1,111.4-1,111.5 ft.) around June 28-29.
The projected peak timing and elevation will fluctuate from day-to-day if there is significant change in the precipitation forecast, or if actual rainfall differs significantly from what was forecast.
At Namakan Lake and Crane Lake, the level has receded by five cm (two inches) since the peak on June 18 at 341.55 m (1,120.6 ft.)—the highest level since 1967.
Below the dam, the level of Rainy River at Manitou Rapids has declined by 1.23 m (four feet) from its record peak on June 17.
Both Namakan Lake and the Rainy River are expected to continue to decline over the next week in the absence of significant rainfall.
The International Rainy-Lake of the Woods Watershed Board suggests waterfront property owners and users of the system keep themselves updated on basin conditions.
Information can be found by following the board’s page on the IJC website at or by calling 1-800-661-5922 ext. 3.


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