ALAMEDA -- Opponents of a possible plan to build homes near Robert Crown Memorial State Beach say they may ask voters to support rezoning the land as a way to expand the beach and promote open space.

The announcement from the San Francisco Bay Chapter of the Sierra Club and the Friends of Crown Beach comes as the two groups have formed an exploratory committee to review how they can prevent the construction of any residential units on the surplus federal property.

"This beach is public property enjoyed by the community and by school children for outdoor education," Norman La Force of the Sierra Club said in an Oct. 30 release. "We are working together to explore every option to stop our public beach from being turned into a private development."

The East Bay Regional Park District is currently suing the city over its decision to rezone the neighborhood, which includes the surplus property and the district's Crab Cove Visitor Center, saying the change was not compatible with nearby recreational uses.

The legal challenge, filed in November 2012 in Alameda County Superior Court, follows the park district failing to obtain the surplus property through an online auction held by the General Services Administration last year, when the district lost to a private developer.

Alameda officials have called the lawsuit a "waste of taxpayer dollars" and say it is an attempt to reverse the auction outcome.

The four-acre site -- known as "Neptune Pointe" -- is located along McKay Avenue and west of Crown beach and Crab Cove. A parking lot on the property has spots for about 40 vehicles.

The neighborhood was one of several where the City Council adopted zoning changes last year to meet the city's affordable housing and other residential needs.

The changes also brought the Housing Element of the city's General Plan into compliance with state law, which city officials say is necessary to be eligible for grants for transportation and other projects.

In their lawsuit, park district representatives contend the council did not provide proper notice about the rezoning from administrative and office use to multi-family residential, and that it approved the change without a completed Environmental Impact Report.

Park officials also say securing Neptune Pointe would allow the district to increase parking, expand the Crab Cove Visitor Center and protect Crown beach.

Both sides are set to return to court Nov. 26 for a case management conference.

The winner of the auction for Neptune Pointe was STL Companies LLC. It has designated Roseville-based Tim Lewis Communities as the developer.

The price of the lot was not immediately available, but the opening bid was set at $1 million, government records show.

Along with the local chapter of the Sierra Club, the Friends of Crown Beach is part of the exploratory committee working to stop residential units on the site.

The committee's aim is to "investigate our options for stopping this private shoreline development which would prevent it from inclusion in Crown memorial state beach," said Karin Lucas of the group.

Contact Peter Hegarty at 510-748-1654 or follow him at Twitter.com/Peter_Hegarty.

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