VACAVILLE -- The local branch of Visiting Angels, a national home care agency, is now expanding into Solano County after the team that runs operations in Santa Rosa and Napa purchased another franchise in Vacaville.

The agency, started locally by licensed clinical social worker Marian Cremin in 2007, said it has seen significant growth since then, especially as the population across much of the North Bay has grown older.

The Santa Rosa location started with just six employees and has now grown to three offices with 100 employees in the field and nine administrative staff, according to Albert DeSilver, who co-owns the agency with Ms. Cremin.

That number is likely to grow, Mr. DeSilver said, with the Solano County expansion and with demand increasing among the senior population. Visiting Angels serves between 80 and 100 clients per week in Sonoma and Napa counties “and  we expect that to grow by 50 percent in the next year in Solano,” he said.

The company also recently hired 15 new caregivers in the last month, along with a new care coordinator for Solano County, Mr. DeSilver said.

Ms. Cremin said a rapidly aging population, coupled with the rising costs of nursing home care and depleted retirement funds, has created an urgent need for in-home elderly care.

“The elderly is the fastest growing segment of the American population, with about 14 percent of Americans now over the age of 65,” she said.  “At the same time, working families have less time to spend caring for their aging parents, which has created a real crisis in America."

North Bay counties are among the oldest counties in California. In Marin County, 18.2 percent of the population is 65 years or older as of 2012, according to the U.S. Census Bureau. In Sonoma County, the number is 15.2 percent of 65 and older; in Napa County, 16 percent of the population is 65 or older. Solano County is much more in line with the state average, with 12.4 percent of its population listed at 65 and over. The statewide average is 12.1 percent.

Visiting Angels Vacaville is one of more than 450 offices nationwide for the Pennsylvania-based company.