By Graeme McNaughton/The Oshawa Express
The snow may be piled high, but the water levels remain low for Oshawa’s watershed.
According to a news release from the Central Lake Ontario Conservation Authority (CLOCA), a lack of rain during the autumn months leading into winter has kept the area’s aquifers missing much needed water.
The conservation authority first issued a Level 2 low water condition in August, upgrading from a Level 1 issued the month before.
The genesis of the low water levels stems from the end of a winter earlier this year that saw below normal levels of snow, followed by a lack of rainfall all through the year.
“We didn’t have much snow pack in the spring to melt or try to recharge aquifers or the groundwater, and that just progressed through the spring and through the summer,” Neil MacFarlane, an environmental engineering analyst for CLOCA, tells The Oshawa Express.
“Normally we get rainfall starting in September through October in this part of the province, and that didn’t happen.”
Between April and November, the local watershed received approximately 400 millimetres of rain – well below the average 625.
And while heavy snowfall, such as that seen on Dec. 15, can somewhat help restore water levels, it doesn’t do much good once the ground starts to freeze, preventing any water from infiltrating beneath the surface.
“At the bottom ends of our watersheds…we had approximately 20 cm, and up in the headwaters we’re up to 25 cm. That’s an equivalent of about 40 mm of water sitting in that snow pack. But that’s not enough,” MacFarlane says of the snowfall on Dec. 15.
“We need about four days, generally, of about the eight degree mark to start getting melt and runoff.”
And because of the sustained low water levels, MacFarlane says that once temperatures start to warm up, the local area needs rain. A lot of rain.
“We need a lot of water, although not at once. If we were to do rainfall, we would need 20, 25 millimetres every third day for several months to get enough infiltration to start recharging aquifers,” he says.
“It’s a prolonged thing now to get that rainfall and recharge.”