Pouhala Marsh Wetland Restoration

Oceanit prepared a Draft Master Plan for the 70-acre Pouhala Marsh State Wildlife Sanctuary and environmentally sustainable designs for wetland enhancement and waterbird habitat development to create habitat for four species of endangered Hawaiian waterbirds.

Challenge: Pouhala Marsh was previously a productive wetland, prior to the development of Waipahu, abundant with native fish, crabs and birds. The urban development in the area severely degraded the wetlands with silt accumulation, water pollution, and invasive species. Oceanit prepared a Draft Master Plan for the 70-acre Pouhala Marsh State Wildlife Sanctuary (PMSWS) and environmentally sustainable designs for wetland restoration and enhancement and waterbird habitat development within the PMSWS. The purpose of this project is to construct tidal wetlands within the PMSWS to create habitat for four species of endangered Hawaiian waterbirds.

Innovation Delivered: Oceanit completed the following tasks under this project: 1) Evaluation of existing plans; 2) Hydrological study using new shallow monitoring wells, rainfall and evaporation gauges, and surface water monitoring gauges; 3) Evaluation of potential water sources (quantity and quality) for constructed wetlands; 4) Topographic survey of proposed development site; and 5) Design of constructed tidal wetland alternatives including construction cost estimates. The Draft Master Plan addressed water exchange between Waikele Stream, Kapakahi Stream, Pouhala Wetland, and Pearl Harbor; pedestrian access; wetland educational activities, wetland maintenance and management; and invasive vegetation and predator control and management.

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