The U.S. Bureau of Reclamation is preparing for a public meeting later this month to update people about problems at Red Willow Dam.
The bureau says it found tension cracks in the dam's embankment last fall.
The water level has been drawn down to around 2,550 feet in elevation for safety reasons and to ease the investigation.
The bureau says there have been no leaks or unusual seepage.
The meeting is set for Feb. 18 in the Community Building at Red Willow County Fairgrounds.
Red Willow Dam is 126 feet tall and it forms a reservoir of 85,070 acre-feet. It's about 11 miles north of McCook.
The bureau says the drawdown resulted in a loss of water supplies for the 2010 irrigation season and, possibly, 2011.