Wetlands Committee

Beach Drive / Marina Inlet

History

Prior to the construction of the Loch Lomond Marina in the early 1960's, the area now identified as the Beach Drive/Marina Inlet was open to the San Francisco Bay.  Beach Drive is in the Bayside Acres subdivision. This photo was taken in the 1950's.

The wetlands to the west of Beach Drive regularly was purged and kept fresh by tides from the Bay through a flap gate and pipe under Beach Drive. See Beach Drive Wetlands for more information on the restoration of this wetlands area.

A dike was constructed along the eastern edge of the planned marina, extending into the Bay and forming a protective "arm" around the marina site. The area behind the dike was then filled from the dredging required to construct the marina. The result of this construction was to form a narrower inlet, or channel, where there was once open Bay access, as can be seen in this photo.

This blocked the open access to Bay waters formerly enjoyed by residents along Beach Drive and Pt. San Pedro Road as well as restricting water flow into the wetlands, putting a strain on the health of those wetlands.

Subsequent dredging in 1967 to maintain this inlet added addition silt behind the dike.

At some point after the dredging, a portion of the dike failed and collapsed into the inlet, causing a severe narrowing at that point. This point also happens to be roughly the narrowest point of the access channel, making the failure of the dike all the more serious. This failure was never repaired by the Marina owners and, over the intervening years, the inlet has been slowly filling in with silt.

This photo vividly demonstrates the damage being caused by this unrepaired failure of the dike.  The inlet is slowingly filling with silt, further constricting the flow of water, isolating the homes that at one time had clear Bay access and continuing to threaten the wetlands to the East.

There is also a clear danger to the wetlands that are part of the Marina property just west of the dike and to the waterfowl that depend on these wetlands on a regular basis.

This final photo demonstrates the increasing disappearance of the waterway and wetlands with the growth of grasses in the area filling with silt. If this process is allowed to continue, the inlet/channel will soon disappear and the adjacent wetlands along with it. The solution requires repairing of the dike and, possibly, dredging of the inlet. Other actions may also be required.