Snow from the mountains eventually becomes the water stored in Nebraska's largest reservoir, Lake McConaughy, but it makes a few stops along the way.
"Under normal circumstances the snow pack that develops and runs off from the mountains is next year's water supply," explains Central Nebraska Public Power and Irrigation District Public Relations Coordinator Jeff Buettner. "Lake McConaughy depends on return flows from irrigation projects in eastern Wyoming and western Nebraska."
Buettner says that last spring when snow pack was more than 200% above average, the reservoirs in Wyoming couldn't hold all the water, and let more go directly downstream causing above average inflows in Lake McConaughy.
This led officials to expect above average inflows this year from those return flows, but CNPPID's civil engineer Cory Stienke says that hasn't been the case.
"Last year's flows were record flows coming into Lake McConaughy and through Lake McConaughy but this year the inflows - I would have expected them to be above normal and we're below normal," he says. "We've been that way all spring, so that's surprising."
So where is the water going? Stienke says diminished return flows are mostly caused by upstream groundwater development and improved irrigation efficiency by farmers in eastern Wyoming and western Nebraska.
"They don't put as much water on the crop therefore not as much water returns to the river through surface runoff or groundwater recharge," says Stienke.
CNPPID is calling these below average inflows the "new normal" for Lake McConaughy.
"It definitely presents new challenges, there are still the same demands on Lake McConaughy," says Buettner. "What we're dealing with is a lower annual average water supply and as a result we've had to make adjustments and that's an ongoing process."
Water released from Lake McConaughy goes on a long journey supplying several hydro plants before feeding into canals and becoming irrigation water.
Buettner says this year's lower inflows shouldn't cause any power or irrigation problems. He says they are keeping an eye on next year since snow pack this winter was much lower than average.