It covers approximately 3.99 square miles. The City has about 230 acres of parkland, much of which is located along or adjacent to the Rahway River. The entire City of Rahway lies within the watershed of the Rahway River and three major streams pass through the City. Rahway's topography is generally level and unvaried and the primary hazard to the City is flooding. Because Rahway became urbanized prior to the advent of measures to control the rate and velocity of stormwater runoff, the volume of runoff exceeds the capacity of the natural drainage system to absorb precipitation.
Erosion is also a natural hazard in the City.
The City of Rahway has been working with their Police, Fire, Health, Public Works, Building, Planning and Economic Development, Recreation, Code Enforcement, Law and Finance Departments, as well as Union County's various departments, the NJ Department of Environmental Protection, the U.S. Army Corps of Engineers, FEMA, the Rahway and Union County Chambers of Commerce, The Rahway River Association and the Rahway River Intergovernmental Cooperation Committee to forge the partnerships essential to a successful Project Impact Community. The City of Rahway has undertaken several projects to address their flood hazard issues. The City has adopted a comprehensive Floodplain Mitigation Plan and this plan addresses the various hazards and explores approaches to mitigation. Major acquisition and elevation projects are in the works to address repetitive losses in the community.