Residents urged to continue conserving water

Driving a dirty car? City officials hope you’ll put off washing it for a few more days.

Water conditions in the Oldman River have improved noticeably in the last couple of days, they say. But it will take a few more days for the city’s water system — which serves surrounding communities as well — to replenish its reservoirs.

That process, officials explain, depends on residents and businesses continuing to conserve water as much as possible. It will take about 20 million litres of water to bring water supplies back to normal.

Production of potable drinking water at the city’s treatment plant was curtailed late last week by extremely muddy conditions and high turbidity. Warm days in the foothills brought rapid snow melt as well as ice jams along the river.

Staff at the water treatment plant deal with turbid water every year — often later in the season — but they faced greater challenges this time. The water is colder in February and March, they explain, and that means the chemical reactions involved in the water treatment process take longer.

At the same time, the settling process prior to filtration is less effective because cold water is more dense than warm water.

Adding to that is the rate at which river conditions can change.

An ice jam last Thursday resulted in the river turbidity changing in just one hour from less than 500 Nephelometric Turbidity Units to more than ten times that level. By comparison, high water in June — even during the flood of 1995 — can result in similar changes that take place over a period of three or four days.

Until the recovery process is complete, city departments will be doing their part by cancelling routine vehicle washes. For the next few days, transit buses, police cars and fire trucks may look just as dirty as residents’ vehicles.

Outside the city, residents of Coaldale, Coalhurst, Picture Butte and smaller centres have also been asked to conserve water. The city supplies potable water to a number of communities and businesses throughout the county.

County and city residents are asked to delay such water consuming activities as laundry, pressure washing and long showers.

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