Blackwater streams are found in sandy lowlands, mainly in the panhandle where fine-grained soils retard the downward percolation of precipitation. Such sands are often saturated with water that is only slowly released from below-ground into the channels of nearby rivers. Blackwater rivers are usually free of suspended particles due to the filtration action of the sand, but are reddish black in color from the high content of organic tannins that have been leached from decaying vegetation. [Click here for Blackwater river info](http://en.wikipedia.org/wiki/Blackwater_river)