Level Reaches Overflow Spillway at Rainy Lake Dam
International Falls, MN, Fort Frances, ON — The level of Rainy Lake continues to rise as a result of June rainfall far in excess of normal across the drainage basin. The level of the upper Rainy River, between the outlet of Rainy Lake and the International Falls-Fort Frances dam has risen close to elevation of the overflow spillway in the center of the dam. This spillway is designed to safely pass additional flow at high lake levels. The rate of flow over the spillway will increase gradually as the lake level rises.
Inflow to Rainy Lake resumed declining yesterday following rainfall over weekend. Rainy Lake water level is forecast to rise roughly 10-15 cm (4-6 in) over the next 7 days. Meteorological forecasts suggest the possibility of more rainfall in 6-7 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 (1111.4 ft – 1111.5 ft) approximately 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 5 cm (2 in) since the peak on June 18 at 341.55 m (1120.6 ft), the highest level since 1967. Below the International Falls-Fort Frances Dam, the level of Rainy River at Manitou Rapids has declined by 1.23 m (4 ft) from its record peak on June 17th. Both Namakan Lake and Rainy River are expected to continue to decline over the next week in the absence of significant rainfall.
The Board suggests that waterfront property owners and users of the system keep themselves updated on basin conditions. Up-to-date information can be found by following the International Rainy-Lake of the Woods Watershed Board’s page on the IJC website, www.ijc.org or call 800-661- 5922 ex. 3.