The city of Laurel filled a portion of the Yellowstone River bottom with 300 tons of rock on Saturday in order to preserve the city’s water supply.
Three weeks ago, city crews built a rock dam in the river to divert water toward the city water plant’s intake, but the river level has continued to drop well below the intake surface, threatening the city’s only water supply.
“What we’ve discovered is that there is about four feet of riverbed that has been scoured away next to the intake leaving a significant hole,” said Public Works Director Kurt Markegard. “Until about four weeks ago, we hadn’t realized how bad the scour was.”
The record-low water level has compounded a crisis that developed in the aftermath of 2011 flooding that scoured the riverbed surface. As a result, the river migrated south and left the city water plant’s intake out of the main channel.
“This is only a temporary solution,” said Markegard. “We know we can’t have this here, and we don’t want it here. But, right now we have no other options.”
Laurel has only one day’s supply of water in its reservoir, Markegard said. “The situation is urgent,” he said.
The two-foot tall rock wall will extend from the water intake to the north bank of the river and will be entirely submerged, funneling the river to the intake, which was built in mid-channel at a cost of $3 million in 2003.
The combined weir projects, have cost the city about $50,000, Markegard said.
“We don’t have a long-term solution yet,” Markegard said. “It’s a matter of funding, and we are hoping FEMA will recognize the urgency of the situation.”