Province IssuesFlood Outlook: Moderate to Major Risk

PROVINCE ISSUES FIRST 2017 FLOOD OUTLOOK – – – Flood Risk Remains Moderate to Major Across the Province: Pedersen Levels of spring flooding will be dependent on future weather conditions as the first 2017 flood outlook suggests the risk of moderate to major flooding persists in many areas of the province, Infrastructure Minister Blaine Pedersen announced […]

via Province issues latest flood forecast : Moderate to Major Risk  — Delta Beach Association Website

Typo in update

There was an unfortunate typo in Sunday’s update – it should have read as follows.

The level of the Shellmouth Reservoir fell 1.55 feet on the week and is currently 1387.07 feet. It is now nearing its minimum level for March of about 1383.2 feet. At the current rate of decline, the reservoir will get to this level in the next three weeks.

SF

Lake Manitoba update: Feb. 26, 2017

The cool weather has returned, slowing the arrival of spring. Flow on the Waterhen River was headed upward this week, reaching 4,977 cfs. This rise however, appears to have stopped with the return of cold weather. Outflow at Fairford remains unchanged on the week at 6,248 cfs. Lake Manitoba fell to 812.41 feet, down 0.04 feet from last week. Flow on the Whitemud River remains low at 88 cfs. Lake Winnipegosis is 833.71 feet, down from 833.77 feet last week.

The gauge reading on Lake St. Martin last week was indeed an anomaly. Its correct level is 802.23 feet feet and this level is currently falling.

The level of the Shellmouth Reservoir fell 1.55 feet on the week and is currently 1387.07 feet. It is now nearing its minimum level for March of about 1383.2 feet. At the current rate of decline, the reservoir will get to this level in the next three weeks. This will leave maximum storage capacity for Assiniboine River flows during the spring freshet. Flow on the Assiniboine remains high, registering 2,549 cfs at Headingly: the gauge at Holland is currently offline.

River update
Time: 9:00 AM February 26, 2017
Portage Diversion: closed
Assiniboine at Holland: offline
Assiniboine at Headingly: 2,549 cfs
Waterhen: 4,977 cfs
Whitemud: 88 cfs
Fairford: 6,248 cfs
 
Lake update
Time: 9:00 AM February 26, 2017
Steep Rock: 812.40 ft
Westbourne: 812.43 ft
Mean level: 812.41 ft
Lake St. Martin: 802.23 ft
Lake Winnipegosis: 833.71 ft
Shellmouth Reservoir: 1387.07 ft

Lake St. Martin update Feb 21, 2017

The gauge reading reported on Sunday for Lake St. Martin (803.31 feet) was indeed an anomaly. The current level of Lake St. Martin is 802.33 feet, below the level (802.7 feet) at which the Ministry of Infrastructure had proposed opening the Emergency Channel. Lake St. Martin peaked at 802.56 feet on the 10th of February, and has fallen about 2/10th of a foot since then.

Lake Manitoba update: Feb. 19, 2017

The unseasonably warm weather and slow melt is good news on the flood front. Otherwise the week was unremarkable with the exception of an odd gauge reading on Lake St. Martin. Lake Manitoba was almost unchanged on the week, with a current level of 812.45 feet. Outflow at Fairford (6,248 cfs) fell slightly from last week, while inflow from the Waterhen River (4,660 cfs) rose slightly. Flow on the Whitemud River remains at its winter low of 86 cfs. Lake Winnipegosis is 833.77 feet, unchanged from last week.

The gauge on Lake St. Martin showed a sharp, almost instant, rise to 803.31 feet this week. This is suspicious and suggests that the gauge is ice affected. If the level is genuine (I am skeptical), then Lake St. Martin has quickly surpassed flood level.

The level of the Shellmouth Reservoir fell 1.64 feet on the week and is currently 1388.62 feet. Flow on the Assiniboine remains high, with a flow of 2,471 cfs at Holland and 2,453 cfs at Headingly.

River update
Time: 9:00 AM February 19, 2017
Portage Diversion: closed
Assiniboine at Holland: 2,471 cfs
Assiniboine at Headingly: 2,453 cfs
Waterhen: 4,660 cfs
Whitemud: 86 cfs
Fairford: 6,248 cfs
 
Lake update
Time: 9:00 AM February 19, 2017
Steep Rock: 812.42 ft
Westbourne: 812.48 ft
Mean level: 812.45 ft
Lake St. Martin: 803.31 ft
Lake Winnipegosis: 833.77 ft
Shellmouth Reservoir: 1388.62 ft

Lake Manitoba update: Feb. 12, 2017

This was a week of little change. The level of Lake Manitoba fell slightly (2/100ths of a foot) to 812.46 feet. Outflow at Fairford (6,389 cfs) exceeds inflow from the Waterhen River (4,483 cfs), which means that Lake Manitoba should continue to decline slowly before the spring freshet. Flow on the Whitemud River remains at its winter low of 106 cfs. Lake Winnipegosis is 833.77 feet, down very slightly from last week. Lake St. Martin continues to rise rapidly and has reached 802.53 feet.

The level of the Shellmouth Reservoir fell 1.6 feet on the week and is currently 1390.26 feet. Flow on the Assiniboine remains high registering 2,436 cfs at Holland and 2,464 cfs at Headingly.

River update
Time: 8:00 AM February 12, 2017
Portage Diversion: closed
Assiniboine at Holland: 2,436 cfs
Assiniboine at Headingly: 2,464 cfs
Waterhen: 4,483 cfs
Whitemud: 106 cfs
Fairford: 6,389 cfs
 
Lake update
Time: 8:00 AM February 12, 2017
Steep Rock: 812.45 ft
Westbourne: 812.47 ft
Mean level: 812.46 ft
Lake St. Martin: 802.53 ft
Lake Winnipegosis: 833.77 ft
Shellmouth Reservoir: 1390.26 ft

Lake Manitoba update: Feb. 5, 2017

The gauges across the province have been working only intermittently in the last few days, providing sporadic readings (the latest reading was last night about midnight). It appears that the good news from last week was short-lived. The most recent gauge readings are showing a level of Lake Manitoba back near the top end of the operating range: it is currently 812.48 feet. This means that we have about 18 inches of free board before Lake Manitoba reaches its flood level of 814.0 feet. In a normal year, Lake Manitoba rises 6 to 18 inches during the spring freshet. With flooding on the lower Assiniboine more or less guaranteed,  which will mean a substantial use of the Portage Diversion in April and May, and with record inflows from the Waterhen River to the north, the best case scenario is that the lake rises to somewhere between 813.5 and 814.0 feet in June. For those making preparations for potential flooding, we now have about 10 weeks until flood season begins.

Lake St. Martin continues to rise rapidly (assuming the gauge readings are accurate). It is now at 802.39 feet, approaching the level (802.7 feet) where MI has proposed to open the Emergency Channel. Again, opening the Emergency Channel provides no direct benefit to Lake Manitoba. It only keeps the level of Lake St. Martin lower.

Outflow at Fairford (6,425 cfs) still exceeds inflow from the Waterhen River (4,896 cfs), which should mean that Lake Manitoba will decline slightly before the spring freshet. Flow on the Whitemud River remains low at 138 cfs. Lake Winnipegosis is 833.79 feet, down slightly from last week.

Credit must be given to the Ministry of Infrastructure this year for keeping the Fairford Water Control Structure wide open this winter. Had Fairford flows been reduced over winter, as is normal operating policy, Lake Manitoba would have faced near certain flooding this spring, with the potential for a major flood with a lake level over 815.0 feet. Whatever happens this year, it would have been very much worse without that decision being taken.

The level of the Shellmouth Reservoir continues to fall rapidly and is currently 1391.86 feet. The storage capacity of the reservoir will help reduce peak flows on the Assiniboine during the spring freshet in May and June.

Flow on the Assiniboine remains high, with a gauge reading of 2,683 cfs at Holland and 2,616 cfs at Headingly.

River update
Time: 8:30 AM February 5, 2017
Portage Diversion: closed
Assiniboine at Holland: 2,683 cfs
Assiniboine at Headingly: 2,616 cfs
Waterhen: 4,896 cfs
Whitemud: 138 cfs
Fairford: 6,425 cfs
 
Lake update
Time: 8:30 AM February 5, 2017
Steep Rock: 812.45 ft
Westbourne: 812.51 ft
Mean level: 812.48 ft
Lake St. Martin: 802.39 ft
Lake Winnipegosis: 833.79 ft
Shellmouth Reservoir: 1391.86 ft