Underwater Importance

While the public looks to the water level for signs of floods and droughts, what happens along the bottom of the river might be just as important as what happens along the top.

Kansas City found that out this spring when some of the city’s water utilities’ intake pipes, which draw water for city use from the river, were left high and dry.

“We’ve had enough (riverbed) degradation going on here it’s affecting the water level,” said Dale Blevins, a hydrologist with the USGS. And rather than gamble with the river’s stability, utilities have spent millions of dollars to retrofit their old intake pipes and dig auxiliary wells.

The riverbed level around Kansas City has fallen about 10 feet in the past 50 years. That unexplained erosion, combined with years of regional drought, led to water levels well below average.

“What we’re really after is a stable riverbed,” Chatman said. But before that can be achieved, much more must be understood about how sand behaves in the river.

The USGS will be using new sonar technology to measure and track sand movement on the bottom of the river, Blevins said. But they don’t expect to have working results until at least 2009.

Until then, scientists and engineers will have their instruments trained on the shifting riverbed.

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