If you think Contra Costa County is crowded now, wait a couple decades. According to the Greenbelt Alliance, in the next 30 years the population of that East Bay county will grow by 250,000 people.
And where will all those people live? The Bay Area-based group advocates smart growth; high density residential communities built close to public transportation.
The new Avalon Bay Transit Village at the Pleasant Hill BART station is one example.
"The first step is to really provide a platform for the planning, set the planning environment, so the developer can come in and implement the vision," Avalon Bay developer Jeff White said.
But not every city in Contra Costa County can build a transit village. For one thing, as it is now, BART may not go there.
It's in the communities to the east, places like Antioch and Brentwood, where Greenbelt Alliance points to growth they claim hasn't been so smart.
"These communities have grown greatly over the last few decades. They have relied on developer fees to pay for their infrastructure and community services and that's not a sustainable pattern," Jeremy Madsen from Greenbelt Alliance said.
In Brentwood, battle lines are drawn around Measure F -- the highly controversial ballot measure that would move the urban limit line to allow for the construction of as many as 1,300 new homes in what is now a grassy pasture.
"Why destroy a valuable resource like farmland that could grow good healthy local food, with a low carbon footprint. Why destroy that to build bad housing?" Brentwood farmer Al Courchesne said.
But Measure F supporters say the kind of growth that their initiative represents is smart for their community.
"People like Brentwood because of the beautiful homes. Is this sprawl? We don't feel that it's sprawl. We feel that it's controlled growth because we're doing it in small sections," Measure F organizer Brian Swisher said.
On June 8, the voters of Contra Costa County will have their say on a measure that could define what growth looks in that county for decades to come.