They Hunger by Scott Nicholson

"In a wilderness gorge deep in the Southern Appalachian Mountains, the worst of the natural and supernatural worlds collide.

A crack adventure team is testing two experimental rafts, sponsored by an outdoor gear corporation. Led by Bowie Whitlock, the group plans a three-day run down 13 miles of the most treacherous whitewater in the eastern United States.

An FBI manhunt is underway in the gorge for Ace Goodall, a religious zealot wanted for a series of deadly abortion clinic bombings. Two agents, cut off from outside communication, stumble onto Ace's camp, triggering an explosive trip wire. The blast opens an underground cavern, exposing a long-buried subterranean species to the surface world.

A freak storm floods the river as the creatures swoop down from the cliffs. Cut off from the outside world, at the mercy of the harsh wilderness, the group's only avenue of escape is almost as deadly as the creatures that attack them.

The group must ride the deadly rapids, but not everyone is interested in mutual survival.

Ace has one bomb left.
God is talking to him.
It's raining again.
The dead won't stay dead.

And the creatures...they hunger." (From www.hauntedcomputer.com)

Paperback Info: ISBN 0786017139, Pinnacle, 2007

Website: www.hauntedcomputer.com