Levels and Flows for Rivers, Lakes, Reservoirs and Aquifers

Lakes Report

July 20, 2007

Levels and forecasts for 35 lakes in Manitoba as of July 20th, 2007 are provided on the attached tables for “Southern Manitoba Lakes” and “Northern Manitoba Lakes”.  These two tables contain the following information:

1. Lake levels for July 20, 2007 or the most recent level available.
2. The change in level since April 27, 2007 when a previous report was issued.
3. Predicted lake levels for August 19, 2007.
4. The target lake level for the summer and the desirable range for the lake.
5. Comparative levels for the spring of 2005 and 2006.

Lakes experiencing normal or above normal water levels:

As of July 20, 2007 most lakes in Manitoba were at or above normal summer levels due to wet weather conditions from mid May to early July.

Levels of Lake Winnipeg and Lake Manitoba were very near the top of their operating range and Lake Winnipegosis was at its highest summer level since the mid 1950’s. These lakes appear to have just crested and should decline for the rest of the summer unless widespread heavy precipitation develops. However, they will likely be at above average levels into the autumn unless rainfall from now on is much below average.

Other lakes which were at unusually high levels as of July 20, 2007 included:

• Lake of the Prairies which was above its spillway elevation until July 20th, which is about five feet higher than normal.
• Dauphin Lake which was 0.9 feet above its summer target.
• Rock Lake which was 3.5 feet above its summer target.
• Big Whiteshell Lake which was 1.5 feet above its summer target.
• White Lake which was one foot above its summer target.
• Clearwater, Cormorant, Athapapuskow, Goose and Big lakes near The Pas were all above the summer target.
• Lake St. Martin which was near the top of its operating range.
• Red Deer Lake which is several feet above its normal summer level.
• North Shoal Lake in the Interlake which was about 3 feet above its average summer level.
• Various lakes on the Nelson River due to unusually high flows on the Nelson River.
• Many smaller lakes in the Riding Mountain and Duck Mountain.

Lakes experiencing below normal water levels:

There were no lakes with unusually low levels except for those on the Nelson River which are affected by dam operations when flows in the river are unusually high.

 Lake Of The Woods has recovered to its normal summer level after being at a near record low level during May, 2007.  

Lake Outflows:

The outflow from Lake Winnipeg is much above average, but not at the maximum possible since the lake is still below 715 feet. The lake level is expected to decline significantly from now through August if the weather is dry.

The outflow from Lake Manitoba is near the maximum possible without causing a downstream flooding problem on Lake St. Martin.  High outflows will continue throughout the summer and autumn.

Outflows from Lake Of The Prairies will remain near the bankfull capacity of the Assiniboine River in the Shellmouth area until the Reservoir level has declined to about 1405.5 and will then be reduced gradually.

Whiteshell area lakes were at record high levels during late June and early July but have declined significantly in recent weeks due to dam operations and dry weather. All lakes should be back to normal summer levels by the end of July unless unusual weather conditions develop. Parks staff, under direction of Manitoba Water Stewardship, continue to operate dams in order to achieve desirable levels on the lakes. Manitoba Water Stewardship and Manitoba Infrastructure and Transportation continue to work together to manage lakes and reservoirs in other areas of Manitoba.

Click on the following links to see the data/levels:

Southern Lake Sheet

Northern Lake Sheet