§ 190-215 § 190-215
(2)
(3)
(4)
(5)
[2] Drainage locations which serve 10 or more disturbed
acres at one time and where temporary sediment
basins or equivalent controls are not attainable,
smaller sediment basins and/or sediment traps should
be used. At a minimum, silt fence, vegetative buffer
strips, or equivalent sediment controls are required
for all downslope boundaries (and for those side slope
boundaries deemed appropriate as dictated by
individual site conditions).
[3] Drainage locations serving less than 10 acres may
utilize smaller sediment basins and/or sediment
traps. At a minimum, silt fence, vegetative buffer
strips, or equivalent sediment controls are required
for all downslope boundaries (and for those side slope
boundaries deemed appropriate as dictated by
individual site conditions) of the construction area
unless a sediment basin providing storage for a
calculated volume of runoff from a two-year, twenty-
four-hour storm or 3,600 cubic feet of storage per
acre drained is provided.
Whenever practical, natural vegetation shall be retained,
protected or supplemented. Priority shall be given to
preserving natural drainage systems, including perennial and
intermittent streams, wetlands, swales, and drainage ditches
for conveyance of runoff leaving the project area.
Examples of BMPs for erosion and sedimentation control are
staked straw bales, filter fences, hydroseeding, and phased
development. Many stormwater BMP technologies (e.g.,
infiltration technologies) are not designed to handle high
concentrations of sediments typically found in construction
runoff and must be protected from construction-related
sediment loadings. Construction BMPs must be maintained
while construction or land disturbance activities continue.
Measures shall meet as a minimum the best management
practices set forth in the "New Hampshire Stormwater
Manual, Volumes 1 through 3" and any published DES
regulations.
Off-site surface water and runoff from undisturbed areas shall
be diverted away from disturbed areas where feasible or
carried nonerosively through the project area. Integrity of
downstream drainage systems shall be maintained.
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Hic it Discharge Detection and Eimination Plan
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