Why are frequent opening of the stream mouth beneficial?
• Flooding occurs when the stream level rises above 3.3 ft MLLW. Monthly removal of the sand plug limits flood risk to only when the plug builds higher than 3.3 ft.
• An increased period of connection to the sea mimics the natural (pre-1969) hydrology of the estuary prior to construction of the Kawainui flood control levee.
• More frequent openings allow fish larvae to enter the estuary and adult fish and plankton to travel out into the nearshore ocean enhancing both ecosystems.
• More frequent openings increase salinity and support oyster growth within the estuary.
• Tidal fluctuation in water surface are conducive to the health of waterbird habitat.
• More frequent openings in the summer prevent the estuary from falling to very low surface elevations as a result of evaporation.
• Tidal flow during monthly openings interrupts stagnation that can cause fish die-offs, horrible smells, and conditions that lead to avian botulism.