Erosion & Sediment & NPDES Programs

The total cost of damages caused by sedimentation is about 500 million dollars per year nationally.

Erosion is the wearing away of soil and its parent material (rock) through the natural processes of wind and rain. Sedimentation, which results from erosion, is the transport and deposition of these soils and rock particles to a location away from their origin, usually to the "waters of the commonwealth" such as streams, lakes, wetlands, and stormsewers. Through man’s activities (earth moving activities) however, the rates of erosion and sedimentation are greatly accelerated. The PA DEPARTMENT OF ENVIRONMENTAL PROTECTION (DEP) defines an earthmoving activity as ".. any construction or other activity which disturbs the surface of the land including, but not limited to, excavations, rock, or earth." Interpreted as, if the vegetative cover (grass, and other plant material) is removed or covered, leaving the earth surface exposed, an earthmoving activity has occurred. Without proper controls, the exposed soil will erode.

-DEVELOP and IMPLEMENT A PLAN for controlling accelerated erosion during construction.

- LEAVE IT GREEN Soil covered with vegetation will not erode easily. Disturb only those areas needed to build your home. Grade lawn areas only when ready to plant.

If the site has features such as steep slopes, flowing streams, wetlands, springs or highly erodible soils, specific care and planning must be taken to control erosion. Assistance is available from private consultants or the District.

The PA CLEAN STREAMS LAW AS AMENDED defines sediment as a pollutant. Sediment has become the number one pollutant by volume to the waters of the Commonwealth. The soil particles contained in sediment also carry and retain chemical pollutants such as herbicides, pesticides, and fertilizers. Accelerated sedimentation that flows into the waters of the Commonwealth can:

STORMWATER – NPDES PHASE II

PAG-2 and NPDES Phase II Requirements For Construction Activities

Disturbed

Area

Written E & S

Plan

E & S Plan

Approved

NPDES SW

Construction

Permit

PCSMP

Submitted

PCSMP

Approval

0-5000 Sq. ft

Not required unless in HQ, EV, or other DEP permit requirement (i.e. Ch. 105)

Not required but may be a municipal requirement**

Not required but may be a municipal requirement

5000 Sq. ft t

less than 1 ac

Yes

Not required but may be a municipal requirement**

Not required but may be a municipal requirement

1 to <5 acres w/o point

source to surface waters

Yes

Not required but may be a municipal requirement**

Not required but may be a municipal requirement

1 to <5 acres with point

source to surface waters

Yes

Required

Yes

Individual YES

General NO*

5 or more acres

Yes

Required

Yes

Individual YES

General NO*

*Note: If the permitted activity is in an MS4 municipality, the municipality must ensure the approval of the PCSM plan. The applicant should sent the PCSM plan to the MS4 municipality along with the municipal notification. Even where the approval of the PCSM plan is not required, the permittee must develop and implement the PCSM and certify that the BMPS were implemented in accordance with the PCSM plan when the NOT is submitted.

**Although E&S plan approval is not required under Chapter 102 for these activities, E&S approval may be required by municipal ordinance or if other DEP permits are required, Le., Ch. 105 Joint Permit or GPs.

Erosion & Sediment Pollution Control and National Pollution Discharge Elimination System Program