I sang this one at camp harmony and also while on a river raft trip.
i learned this as sort of a chant years ago..no idea who wrote it.

We are the River
We're gonna wash your levees down
Coming down from the Mountain
We're comin' right down thru your town
We're gonna join with the other rivers
You know, the dam don't stand a chance
Because no dam the man can build will stand
When the sea begins to dance

We're gonna join with the fishes
and help them on thier way
though the man tries to kill them
and frighten them away
From the depths up to the surface
you know the fishes can't be found
Because only water knows where the water flows
when the river's underground
when the river's underground

Maple buds are bloomin'
and the small stream trickles down
snows are a-meltin'
and the river rushes round in town
We'll hav eno more of your reservoirs
keepin' us frm bein' free
because flood time is here my friend
and we're almost to the sea,
you know we're almost to the sea

also
Muddy Water (by the seldom scene)

Mary, take the baby, river's risin
That muddy water's takin back the land...


also a favorite childhood thanksgiving song...
Over the river and through the woods
To Grandmother's house we go.