Since the 1920s motorcyclists have been visiting this area in the hills between Livermore and Tracy to ride the steep hills, rugged canyons, and meandering trails. The state took over the Carnegie State Vehicular Recreation Area in the 1960s.
"When you are out here, you just feel like you are out of the city. It's just so peaceful and relaxing and we usually camp out on the weekends and it's a great feeling," said Jeff Baritell of Hayward.
But it can get congested out there. On a busy day, as many as 700 off road enthusiasts ride 1,300 acres of trails and roads. Hoping to reduce congestion, the state paid $7.8 million in the late 1990s to expand on adjacent land. It bought 3,000 acres, including the remnants of an old coal mining town called Tesla.
"This new expansion will allow us to continue work to provide programs that will actually help with the cultural and natural resources and protection, and also provide high quality motorized recreation," said Joe Ramos, superintendent of the Carnegie State Vehicular Recreation Area.
The plan calls for new hiking paths and designated trails for off-road use that would be largely invisible to people looking up the hillside.
But some environmentalists and neighbors, balk at the idea of turning the rolling hillsides into anything but open space.
Celeste Garamendi and Art Hull are with Friends of Tesla Park.
"We have a chance to save this beautiful piece of land for future generations to enjoy and appreciate," said Hull.
They say Tesla is an important part of California history. In fact, it is home to Native American artifacts, and was used by Spanish settlers as a trail to San Francisco Bay.
"We cannot allow the damage that has occurred at Carnegie SVRA to invade into this wonderful pristine parkland," said Garamendi
Garamendi lives next to the Carnegie State Vehicular Recreation Area. Her husband's family has been here since the 1870s. He's seen how off-road vehicles change the landscape.
"See that rut for example right there, where the trail's going up kind of below the fence line, that hasn't been used for 20 years," said John Connolly, who opposes the park expansion.
Connolly doesn't believe riders will stay on designated trails in an expanded off highway vehicle park.
"And even if they say well 90 percent of them are good guys, 10 percent of OHV users if they violate it, do an incredible amount of damage," said Connolly.
Karen Schambach says the park hasn't been a good steward of the land they've been given. She's with Public Employees For Environmental Responsibility. The group sued the state park department in 2009 over diminished water quality in a creek that flows during the rainy months. The state water board stepped in and ordered the park to make changes.
"You know, they are making some efforts at it, and I guess it remains to be seen, but as long as you have hill climbs like you have here, you're going to have sediment and there's just no way around that," said Schambach.
The park admits there's still work to do adding that they've been busy replanting hillsides and restoring closed trails to prevent future damage -- a promise it says, to improve the experience for everyone who wants to enjoy nature.
"I think that the word is 'balancing act' -- the balance between motorized recreation and the protection. And we have that balance," said Ramos.
Plans for a larger off-highway park are still being drafted. The public comment period is still open and you can find out more about that here: Carnegie General Plan and here: Carnegie State Vehicular Recreation Area
Written and produced by Ken Miguel