Lake Hancock

Lake Hancock estuary covers about 200 acres and is located in Greenbank, on the west shore on Admiralty Inlet.  It consists of emergent saltmarsh, freshwater marsh, lagoon, mudflats, forested bog and scrub-shrub wetland.  It is not technically a lake anymore because a channel broke through into the saltwater. The U.S. Navy has closed this site to civilian access.

Source of fresh water

Freshwater sources are minor runoff and groundwater.

Plants

Agrostis alba, Atriplex patula, Betula gladulosa, Carex spp., Distichlis spicata, Gaultheria shallon, Jaumea camosa, Juncus balticus, Ledum groenlandicum, Lonicera involucrate, Myrica gale, Picea sitchensis, Plantago maritime, Potentilla pacifica, Rubus spectabilis, Salicomia virginica, Scirpus tabemontanii, Spartina anglica, Triglochin maritimum, Typha latifolia, and Urtica dioica.

Man made obstructions to the estuary

This is the most well preserved estuary on the island and is owned and managed by the U.S. Navy. The property is considered part of the Naval Air Station although a portion of the estuary is under the jurisdiction of the Nature Conservatory.  It has a high salinity lagoon and tidal flushing occurs via one of the two outlet channels. The lagoon, mud flats and low saltmarsh are regularly inundated by the tide. Since the channel broke through to the saltwater, creosoted pilings and arsenic pressure treated pieces of wood have moved into the lake and estuary and become trapped.

Description of the historic estuary

Historically this was a saltmarsh.   When the beach berm closed off the basin it became a freshwater lake.  A big storm in 1934 removed a large portion of the beach berm and it again became a saltwater lagoon. This site was used by the U.S. Navy as a bombing site and is closed to human access due to risk of unexploded ordnance.  

Resources

Island County Estuarine Restoration Program

Prepared by Sheldon & Associates, Inc., June 2001

Puget Sound Creosote Awareness project

www.pscap.net/index_m.htm