Valley City’s upgraded water treatment plant will eliminate sulfates from the city’s drinking water, but state officials are still monitoring aquatic life in the Sheyenne River.
Gov. Jack Dalrymple recently suspended the sulfate limits in the Sheyenne River to allow the newly constructed Devils Lake East-End Outlet to operate, draining high sulfate water into the Sheyenne River. Devils Lake has grown from approximately 44,000 acres in the early 1990s to over 200,000 acres over the past two decades.
State Engineer Todd Sando said the state has been conducting water testing since the East-end Outlet project began.
“We tested to make sure the water quality in East Devils Lake would not affect the aquatic life in the Tolna Coulee and Baldhill Dam,” Sando said. “It’s ongoing, what we’re taking looks at. The biggest thing is monitoring the water quality and all the chemistry and really set some guidelines for aquatic life.”
Dalrymple said the state has done past studies on fish, mussels and other various types of aquatic life and how they respond to different levels of sulfates.
“A lot of study has gone into this, but basically our health department – people who are very responsible and very technical – and EPA (Environmental Protection Agency) say that for shorter periods of time, like a few years, 750 will not have a significant adverse effect on the river and on aquatic life,” Dalrymple said. “A permanent level like that eventually has long-term effects but in the short term, you would not have severe damaging effects.”
Sando said the Sheyenne River historically has had sulfate levels in the range of 250 to 300 milligrams per liter. Last year the Governor had extended the sulfate limits to 750 mg/l and the state provided funding for the $21 million water treatment plant, as Valley City relies on the river for 60 percent of its drinking water. The naturally occurring pollutants have a laxative effect on humans when ingested.
The Governor said years of flooding in the Devils Lake region have devastated thousands of people, and if the lake were to overflow catastrophically, the effects downstream would be disastrous.
“Last year, about this time of year, June of 2011, we really had to make it clear that we were within one wet season of Devils Lake potentially over flowing, and after talking about that for 10-20 years, we felt that we were at that point where that was a realistic possibility,” said Dalrymple.
Devils Lake’s elevation has reduced from its June 27, 2011 peak of 1,454.4 feet above mean sea level to 1,452.4 feet, but Dalrymple said more water needs to come off the lake to provide freeboard for= a possible surge of water from the upper Devils Lake Basin.
“That’s a huge, huge improvement; that’s a tremendous amount of water and everybody’s beginning to breathe a little bit easier, But, never the less, at 1,452.4, we are still within a couple of big wet years from being back at that overflow level – not low enough yet to relax,” said Dalrymple.