Most endangered rivers in America

It's the largest watershed in California. Its rivers collect water from 45% of the state's surface area. Nearly 25 million residents depend on the rivers for drinking water, farming, and commercial fishing.

It's the Sacramento-San Joaquin River Delta System. And in the 2009 edition of America's Most Endangered Rivers (TM) -- the annual listing of the nation's 10 most threatened rivers from American Rivers -- it ranks number one.

The top 10 endangered rivers are located, paradoxically, in some of the nation's most rugged and scenic regions. You don't expect to find imperiled rivers in places like Alaska, Idaho, Montana and Minnesota -- lands usually associated with empty spaces, small populations and sparse commercial development.

According to American Rivers, endangered doesn't mean polluted. An endangered river is one that is under serious threat in the coming year, but can be saved through community action.

Is there an endangered river in your neighborhood?