Erosion and Sediment Pollution Control Program Manual.pdf

Runoff Coefficient -----In the Rational Equation, it is the factor chosen to reflect such watershed
characteristics as topography, soil type, vegetation, and land use in estimating the fraction of
total rainfall that will become surface runoff.
Runoff Curve Number -----In TR-55, it is a number used to represent the runoff potential of a specified
area based on the hydrologic soil group, hydrologic condition, and type of cover.
Runoff Event ----- A precipitation event or snowmelt that produces runoff.
Runoff Hydrology -----An estimation of the amount of runoff or the peak flow that can be anticipated
from a design storm.
RUSLE -----Revised universal soil loss equation.
S
S, or s -----In channel calculations, it is the bed slope, typically expressed in ft/ft.
Saltation -----The movement of soil or rock particles by rolling or a series of short bounces along the
ground due to wind, or a stream bottom by flowing water.
Sand -----1. Soil particles ranging from 0.05 to 2.0 mm in diameter; individual particles are visible to the
unaided human eye. 2. A soil textural class inclusive of all soils which are at least 70% sand and
15% or less clay.
Sand Filters -----Filters that provide stormwater treatment when runoff is strained through a sand bed
before being returned to a receiving surface water.
Sandbar -----A ridge of sand built up by currents, especially in a river or creek.
Sandy Soil -----A soil that is composed of at least 50% sand-sized particles.
Sanitary Sewer -----A utility line — typically underground — designed to convey wastewater from a
developed area to a treatment facility.
Saturated Soil -----Soils in which all voids or pore spaces between soil particles are filled with water.
Saturated Zone -----In basin and pond embankments, it is that part of the embankment that is
saturated due to the water impounded by the embankment.
SC -----In channel design, the symbol for critical slope, the slope at which unstable flow occurs within a
given channel. .
Scarified Seed -----Seed which has been subjected to abrasive treatment to encourage germination.
Scarify -----To loosen or stir the surface soil without turning it over.
Scarp -----The nearly vertical, exposed earth surface created at the upper edge of a slide or a breached
area along the upstream slope.
Scenic River -----Areas in or within 100 feet of a watercourse or body of water designated a
component of the Pennsylvania Scenic Rivers System in accordance with the Pennsylvania
Scenic Rivers Act.
Scour -----1. The erosive action of flowing water in streams that removes and carries away material
from the bed and bank. 2. Erosion at the outfall of a pipe or channel.
Scour Pockets -----The erosive action of flowing water in streams that removes and carries away
material from the bed and banks in a particular area.
Scrub-shrub Wetland -----Wetlands dominated by woody vegetation less than 20’ tall.
SCS -----Soil Conservation Service. Now named NRCS.
Scupper -----A small opening, usually vertical, in a deck, curb, or barrier through which water can flow.
Sea Wall -----A structure separating land and water areas, primarily designed to prevent flooding and
erosion caused by wave action.
Seasonal High Water Table -----Shallow water table associated with periods of recent high levels of
precipitation and/or low levels of evapo-transportation.
Section 319 Grant -----A grant under section 319 of the Clean Water Act, which pays up to 60% of the
cost of a project to prevent or control nonpoint source pollution.
Section 401 -----The section of the PA Clean Streams Law that prohibits pollution of waters of the
Commonwealth.
Section 402 -----The section of the PA Clean Streams Law that prohibits activity that have the potential
to pollute waters of this Commonwealth without proper measures to prevent that pollution.
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