Led by Bilfinger Berger Project Investments and comprising Miller Construction and Cofely, the consortium will design, build, finance and operate a big operational base in Bridgewater.

The contract will also involve building two custody and crime investigation centres, two police stations and a tri-force firearms training centre.

Planning applications for each of the four proposed developments will be submitted over the coming weeks.

Construction will start in September, with the first building completed in January 2014 and the last in March 2014.

The tri-force firearms training centre will be built in Portishead, near to Police Headquarters.

This will serve the police forces of Avon and Somerset, Wiltshire and Gloucestershire and enable officers to be trained to the same standard across the three forces.

Avon and Somerset Police Authority Deputy Chair Cllr Claire Gordon said: “This is a good news story for Avon and Somerset.

“It has been a long journey, and I am delighted that in approving the business case, the Home Office and Treasury have recognised the strength of these proposals and the value for money they will deliver.

“This project has met many tests for being affordable and cost effective for taxpayers and will provide many jobs for the local area.”

Chief Constable Colin Port said: “Thanks to the PFI, our custody capacity will increase by 27% once the three new custody and crime investigation centres are completed.

Jitesh Patel, project director at Bilfinger said: “We have designed highly sustainable buildings that are efficient and flexible to respond to future needs.

“Our local supply chain is keen to continue to engage with and provide opportunity for local business and employment.”

The Blue Light Partnership will also deliver facilities management services once the buildings are completed.