storm water management controls (where practicable).
Where this goal is not met, the permittee shall
provide justification for rejecting each practice
listed above based on site conditions.
Velocity dissipation devices shall be placed at
discharge locations and along the length of any
outfall channel as necessary to provide a
non-erosive velocity flow from the structure to a
water course so that the natural physical and
biological characteristics and functions are
maintained and protected.
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1.4.2.1
[Silt Fences
The Contractor shall provide silt fences as a temporary structural practice
to minimize erosion and sediment runoff. Silt fences shall be properly
installed to effectively retain sediment immediately after completing each
phase of work where erosion would occur in the form of sheet and rill
erosion (e.g. clearing and grubbing, excavation, embankment, and grading).
Silt fences shall be installed in the locations indicated on the drawings.
Final removal of silt fence barriers shall be upon approval by the
Contracting Officer.]
1.4.2.2
[Straw Bales
The Contractor shall provide bales of straw as a temporary structural
practice to minimize erosion and sediment runoff. Bales shall be properly
placed to effectively retain sediment immediately after completing each
phase of work (e.g., clearing and grubbing, excavation, embankment, and
grading) in each independent runoff area (e.g., after clearing and grubbing
in a area between a ridge and drain, bales shall be placed as work
progresses, bales shall be removed/replaced/relocated as needed for work to
progress in the drainage area). Areas where straw bales are to be used are
shown on the drawings. Final removal of straw bale barriers shall be upon
approval by the Contracting Officer. Rows of bales of straw shall be
provided as follows:
a.
Along the downhill perimeter edge of all areas disturbed.
b. Along the top of the slope or top bank of drainage ditches,
channels, swales, etc. that traverse disturbed areas.
c. Along the toe of all cut slopes and fill slopes of the construction
areas.
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NOTE: Space rows a maximum of 60 meters (200 feet)
apart in drains with slopes equal to or less than 5
percent and 30 meters (100 feet) apart in drains
with slopes steeper than 5 percent. If drainage
ditches have slopes above and below the 5 percent
limit the spacing should be shown on the drawings.
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d. Perpendicular to the flow in the bottom of existing drainage
ditches, channels, swales, etc. that traverse disturbed areas or carry
runoff from disturbed areas. Rows shall be spaced [a maximum of [_____]
SECTION 01356A
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