Sand is an important resource in the Grand Canyon. It creates campsites for river runners, protects archeological sites, and provides wildlife habitat. But stretches of bare sand have vanished since the construction of Glen Canyon Dam. A new study published last week looks at how the Grand Canyon has changed because of the dam, and what it will look like twenty years from now. KNAU’s Melissa Sevigny spoke with lead author Alan Kasprak, a geoscientist at Fort Lewis College in Colorado.