The project involves replacement of the existing 14-span bridge (E-07) over the NYS&W Railroad and the Wallkill River with a new 6-span bridge, and construction of a new 2-span bridge (E-12) carrying Susquehanna Street across the Wallkill River. The Wallkill River through the project site is a Category One (C-1) water and has a 300 foot Riparian Buffer and Special Water Resource Protection Area (SWRPA). Prepared the storm water management facility design in accordance with the NJDEP Stormwater Management Regulations and SWRPA requirements.
The design consisted of a detention basin (performed flood routing calculations using PondPack), sand filter, and three water quality MTD’s meeting 95% TSS removal. Performed the hydrologic and hydraulic analysis of the Wallkill River which incorporated three bridges (TR-55, HEC-RAS). Prepared a scour analysis for the proposed bridges and made countermeasure recommendations (HEC-18, HEC-20). Performed soil testing for permeability rates and seasonal high water table for the detention basin design. Prepared a Riparian Zone Mitigation/Compensation site alternatives analysis. Prepared a Flood Hazard Area Individual Permit application. Prepared a SWRPA Functional Value Analysis. Prepared a storm water management plan and details of the BMP’s. Prepared a Stormwater Management Facility Maintenance Plan for the BMP’s. Used StormCAD to design the water quality MTD bypass systems.