DANVILLE — A consultant hired by Danville to study different structures for public safety services has recommended the town start its own police force.

Danville police services are now provided under contract with the Contra Costa County Sheriff's Office. However, town leaders are concerned about rising costs associated with the contract — specifically retirement benefits, which are paid in a county system rather than by CalPERS, the California Public Employees Retirement System.

Danville Mayor Newell Arnerich said the Matrix Consulting Group made the recommendation in a presentation during Tuesday's council meeting. He said the council asked town staff for additional estimates on cost and impact to its staff if Danville starts its own force. The issue will return to the council in about a month. The consultants said starting a police force would cost Danville $7.6 million next year, rising to $9.2 million in five years. The same services with the county would cost about $8 million next year, but could jump between $10 million and $13 million in five years, the consultants said.

Current law enforcement positions in the town of about 42,000 include 30 sworn personnel consisting of a captain who serves as the town's police chief, an administrative lieutenant, six sergeants, two detectives, three traffic officers, 16 patrol officers and one school resource officer. Services also include dispatch and communications and town employees

Arnerich said consultants also considered suggesting a combined police force with Danville, Orinda and Lafayette — cities that also have contracted with Matrix Consulting — and Walnut Creek. But Arnerich said the consultant found the costs of a combined force would be slightly higher, and there would be no real benefits to the cities.

San Ramon previously contracted police services with the Sheriff's Office until it broke away two years ago and started its own force.