Posted on: April 27, 2022 | Water Levels
The following message is from Lake of the Woods Secretariat (current reports are at http://lwcb.ca/noticeboard/)
Extremely high flow conditions are occurring in many regions of the Winnipeg River basin. Please exercise caution on or around water bodies.
Rainfall totals from last weekend’s Colorado Low were very high for this time of year, with the highest amounts around Rainy Lake.
This is the sixth straight quarter-month period with well-above average precipitation in the Rainy-Namakan and Lake of the Woods local sub-basins. For the local Lake of the Woods and Winnipeg River sub-basin regions, April precipitation is the highest on record. Upstream in the Rainy-Namakan and Lac La Croix sub-basins, only 2001 has had higher totals.
With the recent heavy rainfall on snow and frozen ground, the rise in flows in tributaries across the region has been rapid. The LWCB was informed that outflow from the Rainy Lake dam at Fort Frances-International Falls into the Rainy River is being maximized in response to the heavy rainfall in that area and rapidly rising Rainy Lake. Tributaries to the Rainy River, including the Big Fork River, Little Fork River, Rapid River, La Vallee River and Pinewood River are near to, or have broken, record high levels for April. The combination of very high flows out of Rainy Lake and from these tributaries has inflow to Lake of the Woods from the Rainy River at an extremely high rate. Additional runoff from around the lake is also contributing to a rapid rise in the lake level.
Lake of the Woods has come up 20 cm in the past seven days. With the extreme rate of inflow to the lake, the level rise is projected to be over 25-30 cm over the next week, but could be higher if precipitation totals are greater than forecast. With this rise, the lake will be quickly approaching the top of the operating level range for Lake of the Woods. Once it is likely that this level range will be exceeded, fully opening the dams in Kenora is required.
In response, the LWCB is directing further outflow increases out of Lake of the Woods this week that are larger and more frequent than normal.
Lake of the Woods outflow was increased from 650 to 725 m³/s on Monday, April 25. Outflow is scheduled to be increased from 725 m³/s to 825 m³/s on Wednesday, April 27. The Winnipeg River is expected to rise as follows in response to this outflow increase, with additional rise possible from local runoff:
Below Norman Dam : 30 cm (12 in)
Above Kimberley Rapids : 24 cm (10 in)
Winnipeg River Marina: 21 cm (8 in)
Near Locke Bay: 21 cm (8 in)
Above Myrtle Rapids: 21 cm (8 in)
Above the Dalles: 20 cm (8 in)
Above Throat Rapids: 21 cm (8 in)
Minaki: 1 cm (8 in)
Additional increases are tentatively scheduled for Friday and Sunday. The LWCB is meeting on Wednesday, April 27 to review the latest data and forecasts and to finalize details for additional outflow increases.
The LWCB’s Notice Board is being updated frequently with the most recent information.
Lake of the Woods Secretariat
800-661-5922 ex 2