North Dakota will not wait for construction of a new water filter to begin operation of a Devils Lake outlet, Gov. John Hoeven said. However, an engineer says high sulfate levels in the Sheyenne River are likely to delay the outlet's first spring water flows.

A state Health Department permit says the outlet may begin pumping Devils Lake water into the Sheyenne beginning next Monday. The permit bars the outlet's operation if water sulfate levels average 300 milligrams per liter over seven days.

At a measuring point where the outlet empties into the Sheyenne, the river's sulfates already exceed that standard, said Dale Frink, chief engineer of the state Water Commission.

"The bottom line is that the sulfate levels in the upper Sheyenne are higher than we thought," Frink said Thursday. "Right now, we probably won't start up on May 1."

The outlet is intended to divert Devils Lake water into the Sheyenne. Since the early 1990s, excess water has more than tripled the lake's size. The National Weather Service predicts the lake is almost certain to reach 1,449.35 feet above sea level later this year, which would be the highest level recorded since North Dakota became a state in 1889.

The outlet is a network of pumps, pipelines and open channels, stretching for about 14 miles from Devils Lake's west bay to a Sheyenne oxbow southeast of Maddock. The Sheyenne is a tributary of the Red River, which flows north into Manitoba's Lake Winnipeg.

The outlet's discharges are being run through a rock and gravel filter to trap unwanted plants and fish. Canadian officials want the outlet's operation delayed until a more elaborate water filter is built, but Hoeven does not believe that is necessary.

"We don't need another filter," Hoeven said. "The water's fine. We've done exhaustive testing. We have a gravel filter in there as an additional safety measure … but we've really covered it."

Manitoba Premier Gary Doer intends to speak to Hoeven again soon about the state's plans, spokesman Jonathan Hildebrand said Thursday.

U.S. and Canadian researchers took samples from Devils Lake last summer to analyze them for a dozen waterborne species that Canadians feared could be introduced into their waters. None were found.

Hoeven said he does not object to the more sophisticated filter, if the state of North Dakota does not pay to build or maintain it and if it does not interfere in the outlet's operation.

James Connaughton, chairman of the Council on Environmental Quality, said at a news conference in Ottawa this week that Canadian and U.S. officials will meet soon to consider engineering studies on a more elaborate filter.

"We will move forward to do the engineering design work and get the funding, so that construction can begin as rapidly as the schedule and the weather allow," Connaughton said.

The Devils Lake outlet can pump as much as 100 cubic feet per second of water, or almost 2.7 million gallons each hour.

Frink said the river will be monitored closely to spot times when river conditions allow for its operation. Once those conditions appear, Frink said, the outlet can be started up "within a few hours."

(On the Net: North Dakota Health Department information on outlet permit, www.health.state.nd.us/PublicComment/DevilsLakeOutletDischargePermit.)