Baarnum Island / Harbor Isle Drainage Study

Project Details

Client: Nassau County Department of Public Works

Location: Barnum Island and Harbor Isle, NY

Project Summary

LKMA is the Lead Consultant for this Governor’s Office of Storm Recovery (GOSR)-funded project to investigate existing stormwater deficiencies within the Hamlets of Barnum Island and Harbor Isle, located in the Town of Hempstead; and identify flood reduction projects that, when implemented, will address the existing stormwater deficiencies.  During the study phase of this project, the design team coordinated its efforts with the local municipalities including the Town of Hempstead, the Village of Island Park and Nassau County, and held meetings with community groups, including the Island Park Civic Association and the NYRCR Barnum Island/Oceanside/the Village of Island Park/Harbor Isle Committee. The study evaluated the functionality of eleven (11) different drainage systems with outfalls located on Harbor Isle and thirty (30) drainage systems with outfalls located on Barnum Island.  Proposed alternative improvements were developed to identify upgrades to the existing drainage infrastructure to accommodate the design criteria’s rainfall and tidal events.  An important aspect of the study was the prioritization of the proposed drainage improvement project locations, taking into consideration key variables such as the magnitude of flooding, number of homes affected, significance of location (i.e. evacuation routes, schools, emergency services), cost and green infrastructure implementation.  Proposed solutions included road raisings, check valves, and drainage system capacity improvements.