By Hector Mosley, Public Affairs, U.S. Army Corps of Engineers, New York District
The Rahway River is approximately 24 miles long and is a tributary of the Arthur Kill at the heart of the New York-New Jersey Harbor Estuary. The highly urbanized river watershed suffers from frequent flooding due to extensive development and destruction of riparian wetlands and floodplains. Floods have caused damages to houses, businesses and public infrastructure.
The U.S. Army Corps of Engineers, New York District, in partnership with New Jersey Department of Environmental Protection initiated the Rahway River Study in 2012. Municipalities along the Rahway River have suffered extensive damage from Tropical Storms Floyd (1999), Irene (2011), and Sandy (2012). Flood damage screenings led to the identification of the Township of Cranford and the Robinson’s Branch in the city of Rahway as two areas within the basin that experienced regular significant flood damages during storm events.
“The Rahway River Basin Flood Risk Management Feasibility Study is critically important to identifying various flood risk management alternatives for communities along the Rahway River Basin.” said, Col. David A. Caldwell, commander, U.S. Army Corps Engineers, New York District. "Our team of experts including federal, state, and local officials determine the most feasible comprehensive solution, both economically and physically, environmentally and socially, and sustainable, in an effort to ascertain it can be maintained and adapted." said, Col. Caldwell.
On December 9, 2016, the USACE, New York District, and the NJDEP published the Draft Integral Feasibility Report and Environmental Impact Statement (EIS) in the Federal Register. It outlines the Tentatively Selected Plan (TSP) and other alternatives evaluated for the study.
With the publishing of the Draft Integrated Feasibility Report and EIS, a 60-day public comment period was initiated, and will conclude February 7, 2017.
The USACE, New York District, and NJDEP recently held a series of public information meetings in the Township of Cranford, City of Rahway and City of Orange N.J. to discuss the Rahway River Basin feasibility study and solicit public comments.
“The Rahway River Basin Flood Risk Management Draft Integrated Feasibility Report and EIS outlines the elements of the TSP, to provide flood risk management solution in the Rahway River Basin." said, Rifat Salim, project manager, U.S. Army Corps of Engineers New York District. "As part of the National Environmental Policy Act requirements, the Army Corps of Engineers initiates a public comment period and schedules public information meetings within the public comment period to inform stakeholders and the general public about the study details. This allows stakeholders and the public to participate in the study process and provide comments, which are considered in the Final Report." said, Rifat.
As part of the feasibility study planning process potential flood risk management measures were identified, evaluated, and screened. The ones remaining were developed into alternatives, and based on a costs to benefits ratio, two alternatives were selected as the TSP (Alternative 4a and 2a).
Alternative 4a consists of the placement of two 36 in. diameter drainage pipes in the Orange Reservoir Dam to manage water levels two days prior to a storm event, creating storage in the reservoir for excessive rainfall. The Orange Reservoir Dam will be inspected and potentially modified to meet federal regulations. Channel modifications will consist of deepening and widening of the Rahway River in the Town of Cranford, and will contribute to moderate downstream flow, providing flood mitigation to the municipalities of Cranford, Millburn, Springfield, and Union, N.J.
The City of Rahway Robinson’s Branch Alternative 2a consists of a combination of non-structural measures for approximately 21 structures within 10-yr event floodplain, this includes dry and wet flood proofing, ring walls, and elevation.
The next course of action in the study process is to optimize the TSP and update the final report including input from the NJDEP, local governments, resource agencies, and the public.
The Final Report will be submitted to the U.S. Army Corps of Engineers Headquarters for review and approval for a Chiefs Report to Congress for authorization and appropriation/funding to initiate the project construction.