Rainy River Watershed Conditions


The winter of 2014 has been exceptionally cold and snowy in the Rainy River basin, resulting in a very deep snowpack across the region. The large quantity of water in this snowpack increases the risk of high inflows to Namakan Reservoir, Rainy Lake and their tributaries as the spring melt gets underway. In response to this risk, the Water Levels Committee of the International Rainy-Lake of the Woods Watershed Board (IRLWWB) is monitoring conditions closely and directing the dam owners at Rainy Lake and Namakan Reservoir to adjust outflows with the goal of avoiding high peak lake levels this spring.

On March 7th, the Water Levels Committee directed the owners of the dams at Rainy Lake and Namakan Reservoir to operate these dams so as to target the lower end of the regulated lake level range (the Rule Curves) defined by the International Joint Commission (IJC) by the first week of April. In so doing, the Water Levels Committee aims to provide additional storage room in both lakes for the anticipated strong freshet flows.

In response to the directive, the dam owners made small adjustments to the outflows from Namakan Reservoir and Rainy Lake to reach lake levels in the lower portion of the respective Rule Curve ranges as of April 1, 2014. Under normal conditions, the dam owners are required to target the middle portion of the Rule Curves.

Following the significant snowfall of March 31st -April 1st, there is no appreciable precipitation in the medium-range forecasts up to mid-April. Inflows to these lakes and their tributaries are slightly below normal for the start of April, but are expected to rise quickly as the snowpack begins to melt. In response, outflows from the dams at Namakan Reservoir and Rainy Lake will be adjusted with the goal of maintaining the lake levels within the range of the respective Rule Curves.

The Water Levels Committee is regularly monitoring conditions in the watershed and will post updates as conditions warrant.

The latest information lake levels, dam settings, and basin flows can be found online at http://www.ijc.org/en_/RLWWB.

For further information, please call (800) 661-5922 ex 3.