Flood update: May 31, 2015

The last week was spent drying out. River flows everywhere are declining and lake levels are falling. Lake Manitoba is now sitting at 813.07 feet, 0.17 feet lower from last Sunday. Inflow from the Waterhen fell to 7,272 cfs with outflow at Fairford at 11,684 cfs. The flow on the Whitemud River is now just 374 cfs and is falling quickly toward its summer low. Flow on the Assiniboine at Holland is falling rapidly and now sits at 7,872 cfs. The Portage Diversion remains closed.

River update
Time: 10:30 AM May 31
Portage Diversion: closed
Assiniboine at Holland: 7,872 cfs
Assiniboine at Headingly: 9,072 cfs
Waterhen: 7,272 cfs
Whitemud: 374cfs
Fairford: 11,684 cfs  

Lake update
Time: 10:30 AM May 31
Steep Rock: 812.99 ft
Westbourne: 813.16 ft
Mean level: 813.07 ft
Lake St. Martin: 801.25 ft

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Flood update: May 24, 2015

The last week was eventful. The arrival of a Colorado low last Saturday brought heavy rain and strong winds. The Westbourne gauge reached 815.97 feet last Sunday afternoon, nearly two feet above flood level. The heavy rain caused a rise in the lake level, and it is now sitting at 813.24 feet, more than a tenth of foot higher than two weeks ago – it was impossible to get a reasonable read on the lake level last Sunday with the strong winds affecting the gauge readings.

Flows on the Waterhen (8,154 cfs) and Fairford Rivers (12,355 cfs) have returned to more normal levels – the flow on the Whitemud River rose sharply over the last week after the rain, but is now falling currently sitting at 706 cfs.

Flow on the Assiniboine at Holland rose early in the week but has now fallen back to 9,884 cfs today. Flows did not reach the levels requiring an opening of the Portage Diversion which remains closed.

River update
Time: 7:30 PM May 24
Portage Diversion: closed
Assiniboine at Holland: 9,884 cfs
Assiniboine at Headingly: 10,837 cfs
Waterhen: 8,154 cfs
Whitemud: 706 cfs
Fairford: 12,355 cfs
 
Lake update
Time: 7:30 PM May 24
Steep Rock: 813.22 ft
Westbourne: 813.25 ft
Mean level: 813.24 ft
Lake St. Martin: 801.48 ft

Flood update: May 17, 2015

Updated at 12:15

We didn’t need this. The current Colorado Low is delivering heavy rains and strong winds to southern Manitoba. The system extends from the southern prairies to Texas and is carrying moisture northward all the way from the Gulf of Mexico.

On Lake Manitoba, the strong winds from the NE are driving water into the south basin and it is rising sharply this morning. At 9:00 AM, the Westbourne gauge registered a level of 814.70 feet and was continuing to rise quickly. By noon, the level had reached 815.12 feet.  The level of the lake in the north basin is falling, and so too are outflows at Fairford. They are now just 8,119 cfs. At the same time, Waterhen flows have jumped sharply to over 11,000 cfs. This is because the north wind drives water into the south end of Lake Winnipegosis that feeds the Waterhen River.

Flow on the Assiniboine at Holland has fallen this week to 9,743 cfs today, but upstream flows are now rising. This raises the risk of the Portage Diversion reopening. It will be difficult to get a read on the lake level until the wind dies down. The lake will be going up, and it could go up substantially. It will depend on whether Assiniboine flows rise sufficiently to result in a substantial reopening of the Portage Diversion.

River update
Time: 9:00 AM May 17
Portage Diversion: closed
Assiniboine at Holland: 9,743 cfs
Assiniboine at Headingly: 11,014 cfs
Waterhen: 11,014 cfs
Whitemud: 332 cfs
Fairford: 8,119 cfs  

Lake update
Time: 9:00 AM May 17
Steep Rock: 812.63 ft
Westbourne: 814.70 ft
Mean level: 813.66 ft
Lake St. Martin: 801.57 ft

Weather Alert!

According to Environment Canada, we are about to be hit by a Colorado low over the weekend bringing strong winds and 50 to 70 mm of rain and snow. The winds are forecast to be northeast which will raise the level of the south basin of the lake.

The text of the Environment Canada marine forecast for Lake Manitoba is pasted below:
Today Tonight and Sunday
Gale warning in effect.
Wind light increasing to northeast 15 knots early this evening and to northeast 25 late this evening. Wind increasing to northeast 35 Sunday morning and to northeast 40 Sunday afternoon.

Extended Forecast
Issued 03:00 AM CDT 16 May 2015
Monday
Wind northeast 40 knots diminishing to north 20 in the afternoon.
Tuesday
Wind north 20 knots diminishing to north 10.
Wednesday
Wind southwest 15 knots

Flood update: May 10, 2015

This week has seen strong north winds affecting the lake. On Thursday, the wind drove water into the south basin and the Westbourne gauge recorded a level of 814.30 feet. Inflow on the Waterhen River jumped to over 10,000 cfs with the same wind raising the level of the south end of Lake Winnipegosis. The wind has now subsided and conditions have returned to more normal levels. Lake Manitoba now sits at 813.12 feet. Inflow from the Waterhen is now 7,943 cfs. Outflow from Fairford now sits at 12,108 cfs. The Portage Diversion remains open but flows are low, currently 459 cfs.

Flow on the Assiniboine at Holland has fallen this week to just 11,508 cfs today, and upstream flows (Assiniboine at Brandon and the Souris River at Wawanesa) are falling. This removes the need to keep the Portage Diversion open.

In 2014, the level of Lake Manitoba was 812.69 feet on May 10th, half a foot below the current level. In 2011, the lake was 814.19 feet on May 10th.

Lake St. Martin remains above its flood level of 801 feet, currently sitting at 801.48 feet. May 8th was the fourth anniversary of the evacuation of Lake St. Martin. Nearly 2000 residents of communities around Lake St. Martin and the Dauphin River have not yet returned home.

River update
Time: 8:00 AM May 10
Portage Diversion: 459 cfs
Assiniboine at Holland: 11,508 cfs
Assiniboine at Headingly: 12,426 cfs
Waterhen: 7,943 cfs
Whitemud: 424 cfs
Fairford: 12,108 cfs
 
Lake update
Time: 8:00 AM May 10
Steep Rock: 813.06 ft
Westbourne: 813.19 ft
Mean level: 813.12 ft
Lake St. Martin: 801.48 ft