Geology of National Parks: National Park Service Support Project

Scientific Support at Pt. Reyes National Seashore and Golden Gate National Recreation Area

Research Sites

Scientists in the Coastal and Marine Geology Team of the USGS provide scientific support at four sites within the purview of Point Reyes National Seashore and/or Golden Gate National Recreation Area: the Giacomini Wetlands, Abbott's Lagoon, Bolinas Lagoon, and Ocean Beach. Click on a red box in the map below or scroll down to learn more about each site and the research and assistance being provided by the USGS.

To view a larger version of this map, click here.

Lagunitas Creek, as seen from a dike, runs through the Giacomini property

The Giacomini property
The Giacomini property comprises 563 acres of diked lowland at the head of Tomales Bay that the National Park Service intends to restore to tidal marsh. At present, the property is dairyland that was created about 50 years ago; levees and tide gates were constructed to prevent tidal incursion and stream flooding. To design a successful wetland, the site will be surveyed and a digital base map of the park area created, as well as a more detailed survey of the wetland area, using and updating existing Geodetic Postioning System (GPS)-based elevation measurements. Soil and plant types are being evaluated, and river, tidal, and meteorological conditions measured, which can be used to help evaluate or plan habitat conditions when the wetlands are restored.

To learn more about the fieldwork at Giacomini property, click here.

Two extremely hardy invasive plants covering dunes: European Beachgrass and Iceplant. These are two of the species being removed in the restoration areas.

Abbott's Lagoon

Abbott's Lagoon is a dune-restoration site where park personnel are removing invasive plants, especially European beachgrass and iceplant, that have overwhelmed the native vegetation, and altered the dune environment. While the dunes are denuded of these invasive plants, sand transport is expected to accelerate, revegetation may be inhibited, the dunes may migrate landward, and sand migration may cause partial filling of the lagoon. USGS scientists have proposed to study the physical processes driving the retreat to improve the design of this and future dune restoration projects within the park.

Bolinas Lagoon taken from the air. Click here to see the Army Corps of Engineers' proposed dredging plans to increase the water flow within the lagoon.

Bolinas Lagoon
Bolinas Lagoon lies between Point Reyes NS and Golden Gate NRA. A recent study by the U.S. Army Corps of Engineers suggests that sedimentation within the lagoon will close the mouth of the lagoon within the next 50 years. The sedimentation may reduce water volume to the point where tidal flow will be too weak to carry away littoral sand entering the lagoon's mouth, which may result in the infilling of the lagoon. The Corps is considering restoring the lagoon to an earlier condition and USGS scientists are providing advice on the proposed plans as they are developed.

Bedding in beach sand exposed by waves, 10 cm lens cap for scale - Ocean Beach.

Ocean Beach
Ocean Beach borders the City of San Francisco. In the late 1990's, storm waves eroded a section of the bluff behind the beach, threatening city infrastructure, including a highway, sewer pipe, and a sewage treatment plant. To protect those structures, the City placed rock and sand in front of the bluff on a strip of land in the Golden Gate NRA. The Golden Gate NRA and the City plan to develop a long term solution. USGS scientists are providing expert advice to Golden Gate NRA Resource Managers on the potential impacts of various management strategies.

USGS Activites at Point Reyes NRA:

A map of a portion of Point Reyes displaying Abbott's Lagoon and the Giacomini Property, as well as the locations of some tidal and weather guages. Click on the image to view a larger, slower-loading image.

USGS scientists will sit on advisory committees, expert panels, and a public task force, on behalf of Golden Gate NRA and Point Reyes NS resource managers. The following are among those included.

• The Bolinas Lagoon Technical Advisory Committee - This group will act to promote the conservation, protection and restoration of Bolinas Lagoon and its natural surroundings as a unique natural resource; to support scientific study of Bolinas Lagoon; to encourage an active concern for Bolinas Lagoon to the public; and to work with and assist other non-profit and charitable agencies concerned with the welfare of Bolinas Lagoon. With the County of Marin, the advisory committee has been instrumental in initiating a feasibility study by the Corps of Engineers for restoring the Lagoon.
  
• Two expert panels convened by the Corps of Engineers - One panel is charged with evaluating the results of the feasibility study and making recommendations on the direction of the next phase of the restoration. The second panel will evaluate the results of a coincident watershed study.
  
• The Ocean Beach Task Force - A committee convened by the Mayor of San Francisco will evaluate the processes affecting Ocean Beach and make recommendations that will maximize use of the beach by the public while insuring that City infrastructure is protected.