Connections of a River - Connectivity
Vertical disconnects (pg 5
The unintended consequence of this type of
vertical disconnect degrades the QUALITY of the
water. Such vertical disconnects can also
redistribute the quantity of water in local spots.
Runoff is forced to bypass surfaces that it would
normally percolate through (lower levels at point
a) and is instead rerouted to other receiving water
bodies (higher levels at point b).
The effect of these sorts of disruptions is
particularly ruinous to trout streams, which depend
on ample flows of cool groundwater. In effect,
paving over large areas in a small watershed
affects the quality of water supply. The
steady supply of cold, clean water with valuable
dissolved minerals is replaced by intermittent
spates of sediment-laden water of variable
temperature. The effect on a trout stream: erratic
flows, warmer temperatures, siltation, erosion,
rising turbidity-and before long, the loss of
To learn more about impervious
surface impacts, read the EPA's fact sheet titled
"Managing Urban Runoff" at http://water.epa.gov/polwaste/nps/urban.cfm.