LAS VEGAS (AP) -- A top federal water official is hosting a workshop in Las Vegas about drought, climate change and the chance that states sharing the Colorado River may have to do with less water.

Bureau of Reclamation spokesman Bob Walsh said Tuesday that Assistant Secretary for Water and Science Anne Castle and officials from California, Arizona, Nevada, Wyoming, Utah, Colorado and New Mexico are taking part in the WaterSMART conference at the new Aria Hotel.

Interior Secretary Ken Salazar said Monday in Washington that the states should decide now how to deal with the possibility of 20 percent less Colorado River flow due to climate change.

The workshop runs through Wednesday.

The same states inked a pact in 2007 setting rules to cooperate during an ongoing drought gripping the Southwest region.

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