It’s no secret that this past year has been extraordinarily dry in Idaho, with two-thirds of the state experiencing some form of drought.
Now, hydrologists say it’s hitting the Eastern Snake Plain Aquifer hard. With about a month left to go in the current water year, the aquifer has lost 600,000 acre feet of water.
An acre foot measures one foot of water spread across an acre of land, or about 326,000 gallons.
The aquifer is the sole drinking water source for more than 400,000 people between Hagerman and St. Anthony. It’s also heavily relied on for agriculture.
Despite the loss, Alex Moody with the Idaho Department of Water Resources said recharge efforts and pumping restrictions have slowed the aquifer’s drop in storage.
Since 2015, the aquifer has lost 100,000 acre feet of water overall.
“I feel like I can say we’re definitely moderating the decline a bit. We would potentially be below the 1912 storage change volume were it not for aquifer recharge,” Moody said.
The year 1912 marks the lowest point on record when officials began measuring Eastern Snake Plain Aquifer levels.
From then until the 1950s, most farmers used flood irrigation to water their crops. Water not absorbed into the soil funnelled into the aquifer helped to build up the groundwater storage from about one million acre feet to more than 18 million acre feet by the early 1950s.
Over the next 70 years, Idaho lost more than 14 million acre feet of water in the aquifer.
Mike McVay, another engineer with IDWR, told board members Wednesday they’ll have to be resilient under these challenging circumstances.
“This aquifer does leak, we’re going to have undulations in weather and the only way this works is perseverance through the dry times, so try to keep the faith,” McVay said.
The outlook isn’t rosey, either. The National Weather Service predicts a very strong El Niño this winter, typically bringing warmer than normal temperatures and less precipitation.
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