By J.W. Schnarr
The Regional Drainage Committee has received kudos for the work that has gone in to their Southern Regional Stormwater Management Plan from the new provincial minister of agriculture and forestry.
During their regular meeting on July 28, M.D. council accepted for information a letter from Oneil Carlier, minister of agriculture and forestry, regarding the work that has gone into the development of the plan.
“I think we sent this off shortly after the election,” said Reeve Brian Brewin. “Just informing them of our plan.”
The letter indicated that flood events are a concern to all Albertans, and that management of resources is a priority for the provincial government. This commitment includes improving the management of stormwater within current economic realities.
“Having a comprehensive plan that examines potential solutions to mitigate the impacts of future stormwater events is extremely important,” Carlier indicated, adding he was “pleased” that the plan has been a joint collaboration with other municipalities, towns, and irrigation districts in the area.
The area involved is bounded on the north by the Oldman River and South Saskatchewan River, and extends south and west to include the entire drainage area of the St. Mary Irrigation District main canal, the most significant drainage feature in the region.
The eastern boundary is defined by the drainage basin of Seven Persons Creek, which discharges into the South Saskatchewan River in Medicine Hat.
In all, the area comprises 8,000 sq. kilometres (2,000,000 acres) of land, the vast majority of which (61 per cent) is non-irrigated and private irrigation farmland.
In 2010, a 1:100 year rainfall (one per cent chance each year over 100 years) in the eastern and western portions of the study area caused dramatic flooding events across the southern portion of the province.
In the rest of the area, rainfall was significantly less, amounting to somewhere between a 1:10 and 1:25 year event.
While rainfall was much lower in 2011, overland flooding again occurred during dramatic snowmelts and drainage channel restrictions caused by snow.
Again in 2013, flooding occurred in the area but it was primarily limited to Medicine Hat. The flooding was caused by rainfall outside the study area in the Rocky Mountains and foothills leading to high flows in the Bow River basin.
In total, the study proposes seven mitigation options throughout the area studied, with a total price tag of $151 million. These options include:
Chin Reservoir expansion, $39 million; Horsefly Spillway, $46 million; Sherburne Spillway and Reservoir Expansion, $13 million; Sauder (Rattlesnake) Reservoir Spillway, $13 million; Murray Reservoir Expansion, $25 million; Paradise Creek Dry Dam, $13 million; and Drain Inlet Pumping Stations (20 sites), $2 million.
Brewin said the M.D. has reached out to the ministries of Agriculture, Environment, and Municipal Affairs in order to inform the different ministries of ongoing plans. He noted the letter could now be forwarded on to other municipalities and irrigation districts for their information.
“I guess we’ll see where it goes,” he said.
(Editor’s note: the online version of this story cites the Municipal District of Taber in the lede, which has been changed to the Regional Drainage Committee for the online version.)