MIDDLE HARBOR HABITAT
Port of Oakland, California

The Port of Oakland is planning to develop Middle Harbor Habitat using 5.3 million cubic yards of dredged material from the Army Corps of Engineers, San Francisco District’s 50-foot Dredging Project. The project design consists of dredged material placement, rock and sheet pile containment structures, tidal channels, avian roosting islands designed to provide protection from wave action and enhancement of circulation within the habitat area, and approximately 45 acres of eelgrass. Coast & Harbor engineers were responsible for numerical modeling of tide-induced currents and sediment transport, collection of current and wave data, and development of a model to optimize eelgrass habitat survival and enhance tidal circulation.

Coast & Harbor Engineering Members Performed the Following Tasks:

		Collected, processed and analyzed wave and current data for use in calibration and validation of wave propagation and tidal current numerical models.
		Simulated current flow and associated sediment transport with hydrodynamic models.
		Utilized flow and sediment transport modeling results to determine erosion/accretion patterns around the eelgrass habitat and to optimize the design of circulation channels intended to provide adequate flushing and water quality within the habitat.
		Performed 2-D wind-wave generation and transformation modeling to predict stable eelgrass areas within the habitat and provided wave information for design of roosting islands and containment structures.
		Analyzed wave reflection near vertical sheet pile containment structure and potential impact to small craft navigation safety.
		Performed preliminary design of selected coastal elements.
		Provided recommendations for placement of dredged material by hydraulic pipeline and bottom-dump barge to minimize turbidity and sediment movement using results of numerical modeling.
		Designed a public access beach at the northeast corner of Middle Harbor, along with beach view terraces and a seawall at the landward side of the beach.
		Performed 2-D wave propagation modeling to determine wave penetration into Middle Harbor and simulated storm-induced beach profile evolution to predict erosion of the beach fill during storms and to identify beach fill design parameters.
		Performed preliminary and final engineering design of detached breakwater and coarse sand beach alternatives.