Erie County Engineer's Office

Storm Water Rules and Regulations (SWRR)
Version: December, 1994

Chapter Three

Erosion and Sediment Control Measures

Section 3.00 Plan Development Criteria

Effective erosion control planning, see Appendix G, requires a working
knowledge of both the application of control measures in terms of their selection and location and the design of the control measure in terms of its configuration, size and construction. Of utmost importance, however, is a familiarity with the basic criteria that should guide the preparation of all erosion control plans, see Appendix G, regardless of their scale or complexity. These criteria are as follows:

a. Stabilization of Denuded Areas and Soil Stockpiles -

Permanent or temporary soil stabilization should be applied to denuded areas after final grade is reached on any portion of the site. Soil stabilization should also be applied to denuded areas which may not be at final grade, but will remain undisturbed during the construction period.  Soil stabilization refers to measures which protect soil from the erosive forces of raindrop impact and flowing water. Applicable practices include vegetative establishment, mulching and the early application of gravel base on areas to be paved. Soil stabilization measures should be selected to be appropriate for the time of year, site conditions and estimated duration of use.  Soil stockpiles should be stabilized or protected with sediment trapping measures to prevent soil loss.

b. Establishment of Permanent Vegetation -

A permanent vegetative cover should be established on denuded areas not otherwise permanently stabilized. Permanent vegetation should not be considered established until a ground cover is achieved which is mature enough to control soil erosion satisfactorily and to survive severe weather conditions.

c. Protection of Adjacent Properties -

Properties adjacent to the site of a land disturbance should be protected from
sediment deposition. This may be accomplished by preserving a well vegetated
buffer strip around the lower perimeter of the land disturbance, by installing perimeter controls such as sediment barriers, filters or dikes, or sediment basins, or by a combination of such measures.  Vegetated filter strips may be used alone only where runoff in sheet flow is expected. In general, filter strips should be at least fifteen feet (15’) in width. If at any time it is found that a vegetated filter strip along is ineffective in stopping sediment movement into adjacent property, additional perimeter controls should be provided.

d. Timing and Stabilization of Sediment Trapping Measures -

Sediment basins, diversions, sediment barriers and other measures intended to
trap sediment on-site should be constructed as a first step in grading and be
made functional before upslope land disturbance takes place. Earthen structures such as dams, dikes and diversions should be seeded and mulched after installation.

e. Sediment Basins -

Stormwater runoff containing damaging amounts of sediment should pass
through a sediment basin or other suitable sediment trapping facility.

f. Cut and Fill Slopes -

Cut and fill slopes should be designed and constructed in a manner which will
minimize erosion. Consideration should be given to the length and steepness of
the slope, the soil type, upslope drainage area, groundwater conditions and other applicable factors. Slopes which are found to be eroding excessively within one year of construction should be provided with additional slope stabilizing measures until the problem is corrected.

g. Stabilization of Waterways and Outlets -

All on-site stormwater surface channels should be designed and constructed to
withstand the expected velocity of flow from a ten year frequency storm without erosion. Design for a larger frequency storm may be necessary for protection from the stormwater flow. Stabilization adequate to prevent erosion should also be provided at the outlets of all pipes and paved channels.

h. Storm Sewer Inlet Protection -

All storm sewer inlets which are made operable during construction should be
protected so that sediment-laden water will not enter the conveyance system
without first being filtered or otherwise treated to remove sediment.

i. Working In or Crossing Watercourses -

Construction vehicles should be kept out of watercourses to the extent possible. Where in-channel work is necessary, precautions should be taken to stabilize the work area during construction to minimize erosion. The channel (including bed and banks) should always be re-established immediately after in-channel work is completed. Where a live watercourse must be crossed by construction vehicles regularly during construction, a temporary stream crossing should be provided.

j. Construction Access Routes -

Wherever construction vehicle access routes intersect paved public roads,
provisions should be made to minimize the transport of sediment (mud) by runoff or vehicle tracking onto the paved surface.

k. Disposition of Temporary Measures -

All temporary erosion and sediment control measures should be disposed of after final site stabilization is achieved or after the temporary measures are no longer needed. Trapped sediment and other disturbed soil areas resulting from the disposition of temporary measures should be permanently stabilized to prevent further erosion and sedimentation.

l. Maintenance -

All temporary and permanent erosion and sediment control measures shall be
maintained and repaired as needed to assure continued performance of their
intended function. Inspection by the Erie County Engineer or his appointed
inspector shall determine if and when maintenance/repair is needed.

m. Plans and Specifications -

All erosion control practices contained on the plan shall be built to the standards and specifications of the “Water Management and Sediment Control for Urbanizing Areas” handbook.