Erosion and Sediment Control
Erosion and sediment control is one of the primary responsibilities of the Roadside Environmental Unit’s
Soil and Water Engineering Section. The project engineers and technicians in this section design erosion and
sediment control plans for all phases of highway construction to control erosion and sediment on project sites.
These plan designs are based on many factors such as construction sequencing, existing topography, proposed
land grades, soil type, classifications of surrounding waters, critical habitat areas, and any environmental concerns.
The main importance of erosion and sediment control is to protect our waterways. Any type of land disturbing
activity increases the potential for erosion to occur. As eroded soil particles move by water into our waterways
sedimentation is then able to occur. This occurs when the water movement slows and the suspended particles are
allowed to settle. Sedimentation in our waterways leads to fish kills, clogged streams, reduced storage volume
of reservoirs, and added filtration costs for our municipal water supplies. Sedimentation however is not the only
problem of eroded particles entering our waterways. There is also a problem when the smaller soil particles fail
to settle out and remain suspended in the water. These suspended particles block out light filtering through
the water thereby reducing in stream photosynthesis, and altering the ecology of these waterways.
In order to control soil erosion and sediment the Soil and Water Engineering Section strictly follows the
North Carolina Sedimentation Control Law. This Sedimentation Control Law basically prohibits visible off-site
sediment from any land disturbing activity.
Currently the NCDOT has the authority to administer a sediment and erosion control program within the
department’s jurisdiction which consist of the responsibility for preparation, review and approval prior
to construction of erosion and sediment control plans for all land-disturbing activities associated with
highway construction of one or more contiguous acre.