Following the repair or replacement of the existing drainage structures, long-term beneficial impacts would be expected from a reduction in erosion associated with uncontrolled runoff during high-flow events. Berger study, 3-10.

Repair of the existing system would result in short-term adverse impacts, but provide long-term benefits to biological resources in Klingle Valley.  

Repairing the existing system would create short-term adverse impacts but would provide long-term benefits to the flora and fauna communities in the project area.  

Repair of the existing system would help to reduce erosion and subsequent sedimentation associated with high-flow storm events.  

On-going habitat degradation or loss associated with erosion, sedimentation, and degraded water quality would be reduced, thereby resulting in an overall improvement in habitat quality in the project area. Berger study, 3-18

Long-term impacts to the floodplain would be expected due to the modification of the stream channel resulting from the repair of the retaining wall.  On the other hand, the repair of the stormwater and drainage system would stabilize flows, thereby allowing the stream to reach equilibrium and providing long-term benefits.  Berger study, 3-30.

James J. Shabelski, PE, Water and Sewer Design Branch, WASA, states, "Under this alternative, to rebuilding Klingle Road to its Original and Alignment and Dimensions and repair/replace storm drainage, all infrastructure should be built to current standards and codes.  Based on prior DC DPW studies, it would appear that the construction of a new storm drain in the paved road from Woodley Road to Porter Street is the optimum solution.  The channel along Klingle Road should be restored to natural conditions as required by the National Park Service."  Berger Appendix A, Agency Coordination