Section C.2. continued from page 2
The 10-year storm event overtopped the roadway for existing conditions. Overtopping occurs for
the 50-year storm event with proposed conditions. There is no significant change in the 25-year
design storm or 100-year risk assessment storm floodplains. The greatest change in backwater
elevations occurs at the cross section directly upstream of the project location. Backwater
decreases approximately 1.2 ft at this cross section for the 25-year design storm. The proposed
structure will be built under a traffic detour thus avoiding the need for a temporary road crossing.
No wetlands will be impacted by construction of the proposed structure. Shuckers Run is neither
a stocked or wild trout stream. There are no historical resources involved with this replacement
project. The PNDI search resulted in zero known impacts. R-6 rip-rap will be used in accordance
with Design Manual, Part 4, Section 7.2.5. Rip-rap will be placed along the face of the wingwalls
at a 30-degree angle to divert flow into the culvert. All temporary fills will be removed in their
entirety and the affected areas stabilized and returned to pre-existing elevations. The stream will
be diverted around the worksite by a temporary pipe culvert or cofferdams protecting the
excavated areas. The District’s recommendation is to pump construction water through the grass
greater than 50 feet from reentering the stream. The filtering of the water will be performed with
caution and will be favorable to the surroundings. Determination of the use of this temporary
facility will be based on the Department of Environmental Protection’s (DEP) recommendation.
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