By Lisa Knoll Public Affairs Manager, Southwest Kansas |
But with rain comes an often-overlooked issue: stormwater
runoff. Most water that falls to earth
as rain or snow is usually absorbed by trees, plants and the soil, which
naturally filters the water before it flows back into rivers, streams and
waterways.
However, the Federal Highway
Administration reports that precipitation that occurs over highways and other
impervious surfaces, like parking lots and driveways, results in stormwater
runoff that can carry debris, sediment and chemicals into water sources such as
rivers, streams and waterways— diminishing the quality of water sources.
Because stormwater runoff can have devastating effects on
the environment, KDOT works to reduce and control this runoff as much as
possible during construction projects.
This includes implementing an approved stormwater pollution prevention
plan (SWPPP) for each highway project that disturbs one acre or more of
vegetation.
According to Scott Shields, KDOT’s Environmental Program
Administrator, a SWPPP will include both soil erosion and sediment erosion
controls. Perimeter controls are used
during a project until all grade work is completed. Perimeter controls are temporary barriers
that ensure that sediment and contaminants are contained on the project site
and do not end up contaminating surface water.
They include silt fences, erosion controls, rock checks and
biodegradable logs.
Sediment controls are used to control the sediment until the
vegetation grows back. Sediment controls
include perimeter controls, ditch checks and slope barriers. These controls will control sediment runoff
until native grasses grow back. Native
grasses work with the soil to slow down and filter runoff so that surface water
does not become contaminated.
Mulch can be used an erosion control device and is usually crimped in, as shown here, using a spade or roller. |
An erosion control blanket is in place around a box/winged culvert providing protection from rain and wind erosion on highway projects. |
Shields said KDOT has several standard seed mixes.
“Each mix is customized by district and includes cool season perennial grasses along with native grasses that grow well in the area,” said Shields. “Cool season perennial grasses will last one to two years until the native grasses become established.”
He said native grasses are important because they grow
naturally in an area, and provide benefits for pollinator insects, roadside
aesthetics and natural landscapes.
No comments:
Post a Comment