In what advocates described as a watershed moment in efforts to help the homeless, Sonoma County supervisors Tuesday unanimously approved a series of emergency measures assisting people who need to get out of the winter cold.

The board assembled a $141,000 package offering motel vouchers for some and a safe place for others to park and sleep. Homeless activists applauded the county's decision to decriminalize camping in cars, saying it marked an important shift in how the county thinks about people with nowhere to go.

"This is kind of a pinch-me week with regard to the homeless," Carolyn Epple, a retired Sonoma State University anthropology professor, told the board.

"This morning is like a miracle to me, too," said Georgia Berland, executive officer of the Sonoma County Task Force for the Homeless. "The last few weeks have been like a light coming on."

The board approved funding to create a seasonal "safe parking" program for the homeless at the Sonoma County Fairgrounds, which could accommodate up to 50 vehicles and provide the occupants with bathroom facilities, showers, warming stations and a meal. Pets will be welcome, too.

The effort, to be managed by Catholic Charities of the Diocese of Santa Rosa, which already operates numerous shelters in the area, will start Feb. 1 in a parking area south of Aston and Linwood avenues, between Meda and Brookwood avenues.

The parking area will be opened nightly from about 8 p.m. to about 8 a.m., said Mark Krug, the county's Community Development officer. Participants will be required to register at Catholic Charities' Homeless Services Center on Morgan Street.

The board approved $90,953 for the venture, including $62,015 for Catholic Charities' costs and $28,938 to reimburse the Sonoma County Fair. The costs include on-site security and overnight management to ensure the site is properly supervised, Krug said.

An additional $50,000 was authorized for the purchase of about 1,000 hotel vouchers to be distributed by agencies and shelters serving the homeless. They will target parents with young children, people with medical issues that make them especially vulnerable to outdoor living, and those who may have particular trouble accessing shelter.

The safe parking program would run for two months, with an option to extend it to a third month if demand remained substantial and cold or rainy weather were forecast.

However, Supervisor Shirlee Zane, like others, suggested a reassessment of the situation by mid-April, since the fairgrounds can only be used temporarily.

In the meantime, she called within the week for a public meeting to provide details of the plan to neighbors. The outreach could not occur until a site was chosen Tuesday, Krug explained.

One resident, Vic Aiuto, told the board he was alarmed to read about the plan in a weekend newspaper that included a photograph showing his house right across the street.

"We are big advocates of doing everything you can for the homeless," Aiuto said, but there are potential implications for neighbors' quality of life and home values.

"I think the outreach to homeowners is really, really important," he said.

Officials said the last county homeless census, conducted in January 2013, counted 4,300 homeless people in Sonoma County. The number included 837 people living in vehicles with the additional hardship of knowing they could be ordered to move on at any time under an ordinance that, until Tuesday, prohibited anyone from staying in a car for more than three hours.

The changes do not authorize the homeless to sleep just anywhere. Parks open only until sunset, for instance, will still be off-limits, said Deputy County Counsel Ann Keck.

But it will no longer be illegal to park on the side of a road and sleep in unincorporated Sonoma County, as long as person's belongings are contained in their vehicle and they don't pose a threat to public safety by parking unsafely, parking on private property, or leaving waste, Keck and other officials said.

The city of Santa Rosa recently lifted its ban on sleeping in cars, as well, she said.