Dumbarton Gravel Quarry


The Dumbarton Quarry gravel pit, cut into the south end of the Coyote Hills, sinks almost 300 feet below the salt pond waters. For this image I flew the kite from one of the adjacent hills. I suspect that the motorists stopping at the Dumbarton Bridge toll plaza never realize that they are adjacent to such an enormous pit.

Red Hill Gravel Quarry

This is a stitched panorama of four landscape format images taken 3 October 2005.

I was able to glean the following from a 2004 Fremont Planning Commission report recommending the extension of the quarry’s conditional use permit.

On March 25, 1997, the City Council approved a time extension of ten years (to July 1, 2007) for quarrying operations and final rehabilitation of the facility to allow future reuse of the site by the East Bay Regional Park District for inclusion in Coyote Hills Regional Park. The approved project included additional excavation of the quarry area to a depth of approximately –300 feet Mean Sea Level (MSL) and improvement of the site in accordance with the plans developed by the East Bay Regional Park District during the process of rehabilitation of the quarry.

I thought it would be interesting to see if this large pit was evident in the 1939 aerial survey I located in the UC Berkeley map library.

Dumbarton Quarry site in 1939

This is a crop from a 1939 aerial survey showing the segment of the Coyote Hills now quarried for gravel.

The hill was in a pre-pit state at this time (no quary), I understand that the current 300-foot-deep hole has been created during the last 35 years. The full image is also available on Flickr.

One Response to “Dumbarton Gravel Quarry”

  1. Gerhard Ringel Says:

    In your 1939 picture, notice that the Hwy 84 Dumbarton Bridge is also not present.
    Now that it is 2007, I wonder if the plans for closing the quarry and returning the land to the public for recreational use are on track. I have observed that the operation to go deep into the pit and remove more material seems to have stopped in late 2006 and a partial filling of the pit seems to have started.
    I am wondering if the pit will be completely filled or perhaps be converted to a recreational lake.
    When will the area be open as a park?
    Do you have any further information on that?

    best regards,