Riverside Roundabout

Project Location: CR 94, CR 63, CR 104 and NYS 24 Riverside
Client: Suffolk County Department of Public Works

NPV assisted N+P and Suffolk County Department of Public Works with environmental permitting, state environmental quality review, and stormwater management design and permitting for the five-legged traffic circle at CR 94, Center Drive, CR 63, Old East Moriches-Riverhead Road, CR 194, Quogue-Riverhead Road, and NYS 24, Flanders Road in the Hamlet of Riverside, Town of Southampton. The project involved reconstruction of the traffic circle into a two (2) lane modern roundabout with other stormwater and traffic related improvements in order to accommodate bicyclists, pedestrians, and vehicle traffic safely and efficiently.

NPV assisted N+P with development of a new stormwater management system to address direct stormwater outfalls and area site constraints including high groundwater conditions and no vacant land for recharge. The stormwater design met NYSDEC stormwater quality requirements and incorporated two bio-swale areas, shallow leaching structures, and a stormwater treatment system used for pollutant removal from stormwater runoff prior to discharge into the Peconic River. The project is located within environmentally sensitive areas, and required a wide variety of permits including US Army Corps of Engineers Nationwide Permits, a NYSDEC Article 24 Freshwater Wetland Permit, a NYSDEC Article 25 Tidal Wetland Permit, a NYSDEC Wild, Scenic, & Recreational Rivers Permit, NYSDOS Coastal Consistency Concurrence, and a NYSDEC General Permit for Stormwater Discharges from Construction Activity. NPV performed wetland delineations and obtained all environmental permits for the project. Additionally, NPV prepared the environmental review documentation pursuant to SEQRA and assisted the County with SEQRA administration, including presentation to the County Council of Environmental Quality (CEQ).

Relevant Project Components:

  • Drainage Design with Stormwater Treatment Systems and Green Infrastructure
  • Environmental Permitting
  • SEQRA Documentation
  • Stormwater Pollution Prevention Plan
  • Wetland Delineation
  • Preliminary and Final Plans, Specifications, and Estimate Topographic Survey and Mapping
  • Erosion and Sediment Control Plans
  • Traffic Analysis