I was talking to a Lethbridge resident who thought our water came through Calgary.
I said no, it comes from the Oldman River Watershed. I wondered how many other consumers of water in Lethbridge and district don’t know where their water comes from.
A watershed is the area of land where all of the water that is on or under it drains in the same direction. The Oldman River Basin is a big drainage area.
The Oldman River Basin turns into the South Saskatchewan River Basin and all the water travels to Hudson Bay.
The Oldman (sometimes spelled Old Man) River is born up in the foothills and mountain valleys north and west of Lundbreck, west of Highway 22. Perhaps you’ve been camping at Dutch Creek or Livingstone Falls. That’s all part of the Oldman Watershed.
The Oldman Reservoir near Brocket is a combination of water from the Oldman River, the Castle River and the Crowsnest River. The Belly River joins the Waterton River down to the southwest and the Waterton River joins the Oldman River just west of Coalhurst.
From the south-south-west Lee Creek joins the St. Mary River, which then joins the Oldman River just upstream of Popson Park in Lethbridge. From north of Ft. Macleod, Willow Creek joins the Oldman.
During the spring snowmelt, a lot of stuff runs into the Oldman River and its tributaries. Some is from bare soil in the mountains where clear-cutting of forests have denuded the hills and allowed soil to erode into creeks and streams.
Some is the silt that forms when off-road vehicles destroy the vegetation on creek banks and churn up creek beds. Range cattle can do the same thing to riparian areas.
When rivers get close to towns, there is runoff from the streets, roads and highways. There will be pet feces, road salt and sand, and accumulated oil that drain directly into the river in spring.
On either side of every river system on the prairie are square miles of cultivated fields. When large amounts of snow melt quickly and the ground is still too frozen to soak it up, the melt water will carry whatever loose soil, manure and fertilizer there is, off the cultivated farm fields and into nearby creeks and streams.
I’m always irritated by the sight of farmers cultivating right up to the edge of roads or drainage ditches, leaving no barrier of vegetation.
Another possible source of soil sediment could be the new city residential and commercial developments located near the coulees.
Developers clear large areas of topsoil before they begin to build the infrastructure and buildings. If it sits over winter and a large amount of snow falls, and then melts, there could be a lot of dirty run-off into the Oldman River.
The Oldman River can end up holding a lot of sediment. Sometimes it is just too much and the city begs us to stop using water unnecessarily. They can usually keep the quality of water, as long as there is not a large quantity to clean.
Alas, this is one time where they could not produce enough clean water and still maintain the huge amounts they need for fire protection as well. So we must boil our water to kill off the pathogens, or buy bottled water.
This is a good wake-up call for all citizens of this Oldman River Water Basin to think hard about the source of life we get from our rivers. Check out the Oldman Watershed Council website.
Learn how we can keep pollutants and sediment out of our creeks and rivers. Maybe keep a few jugs of clean water in your basement for the next water emergency. Replenish the jugs every three months.