In rivers where flooding is imminent, such as near Fargo, N.D., officials are scrambling to keep needed monitors working and make the cuts elsewhere. Details are still to be worked out, officials said.
Jerad Bales, the agency's chief scientist for water, said at least 120 gauges, and as many as 375 in a worst-case scenario, will be shut down because of the mandatory cuts known in Washington budget language as sequestration.
"It's a life and property issue. It's a safety issue," Bales said in a telephone interview.
Agency flood coordinator Robert Holmes said that without a full fleet of stream gauges, it is harder to warn people about flooding. For example, he said, the Illinois River was rising fast a few nights ago and the National Weather Service forecast was so dire that officials figured it wasn't worth fighting the flood if they were going to lose anyway.
But then new stream gauge data showed that it wouldn't quite be as bad and that the levee could be strengthened enough to hold. So far it has worked, he said.
There are 8,000 gauges across the country, paid for by a combination of federal, state and local governments. The federal government last year spent nearly $29 million on gauges, while other governments pitched in $116 million.
The sequester cuts 5 percent from the federal share and that means shutting down a handful of gauges in each state.
Because it is a joint program, decisions on which gauges to shut down are being made only after federal and state officials meet.
For example, USGS officials originally proposed shutting four gauges in North Dakota, including two on the Red River which is facing what might be a record flood. After meeting with state officials, those two gauges will stay working, but two others may be closed, said Gregg Wiche, who runs the USGS North Dakota Water Science Center.
Fargo Mayor Dennis Walaker said the Red River gauges are crucial not just to weather forecasters, but to the public. Gauges are monitored at times on an hourly basis because "our level of protection is based on what the river is doing," he said.
In Illinois, 10 gauges have hit record high levels, with 53 others at or above flood levels, according to the USGS.
James Lee Witt, who ran the Federal Emergency Management Agency in the Clinton administration during the 1993 Mississippi flooding, said, "There are as many as nine states that will be impacted by spring floods and this not the time to make such harmful budget cuts."
Paul Higgins, a meteorologist who is associate director of the American Meteorological Society's policy program, said cutting federal programs that help the country avoid natural disasters is "a costly mistake."
The gauges will be shut down at different times in different states, starting in May in Idaho and Maine, according to the USGS.
Water levels are important for monitoring drought and keeping nuclear power plants on the river operating, USGS officials said. In Idaho, fisherman and whitewater river rafters use monitors to tell them where they should go, said Michael Lewis, head of the USGS Idaho Water Science Center.