Erosion and Sediment Pollution Control Program Manual.pdf

3 feet should be avoided wherever possible, and cut slopes not in competent bedrock should not be
steeper than 2H:1V. Fill slopes should not be steeper than 2H:1V or exceed 5 feet in height wherever
possible. All cut and fill slopes should be stabilized by seeding and mulching, blanketing, or other
suitable method within 24 hours of reaching final grade. This will require the contractor to anticipate the
date of completion and schedule ahead for seeding and mulching.
Road surfaces should be sloped for drainage. In flatter areas, crowning is the most efficient means of
draining the roadway (Standard Construction Detail # 3-3). For hillside construction, insloping with
adequately spaced cross drains is recommended (Standard Construction Detail # 3-4). Outsloping
roads can be very dangerous. Where crowning and insloping are not sufficient to address drainage
requirements, waterbars, broad-based dips, deflectors, or culverts may be needed. All discharges
should be to stable drainage courses, or to well-vegetated areas. Consideration should also be given if
outlet protection is needed.
PA DEP
STANDARD CONSTRUCTION DETAIL # 3-3
Crowned Roadway
Cut and fill slopes shall be stabilized immediately upon completion of roadway grading. These
areas shall be blanketed wherever they are located within 50 feet of a surface water or within
100 feet of an HQ or EV surface water or where a suitable vegetative filter strip does not exist.
A top dressing composed of hard, durable stone shall be provided for soils having low strength.
Roadside ditches shall be provided with adequate protective lining wherever runoff cannot
sheet flow away from the roadway.
Adequately sized culverts or other suitable cross drains shall be provided at all seeps, springs,
and drainage courses. Ditch relief culverts or turnouts shall be provided at the intervals
indicated on Table 3.3 or Table 3.4 for roadside ditches. Riprap outlet protection to be sized
according to anticipated discharge velocity.
Roadway shall be inspected weekly and after each runoff event. Damaged roadways, ditches,
or cross drains shall be repaired immediately.
363-2134-008 / March 31, 2012 / Page 19