Work on the roundabout, made possible with $500,000 Commonwealth funding, is expected to start next financial year.

Meander Valley Mayor Craig Perkins said the development approval was one of four significant applications to pass at Tuesday's council meeting.

"The roundabout on Westbury Road has been on the cards for a long time," Cr Perkins said.

"It's considered an investment in growth and links to the supermarket and continuing growth in Prospect."

The roundabout was approved during the council's closed session and is considered to be part of continual upgrades for the road as Prospect' Vale's population and traffic flow increases.

Cr Perkins said the approval of a $4.5 million IGA Supermarket for Westbury, a 27-lot subdivision at Deloraine and a six- unit development for Hadspen showed faith in the municipality from investors.

"You've got rural communities still showing population growth, which is promising," he said.

"For somebody to start the process of subdividing land with 27 lots in it shows confidence. Obviously they can get a return from it and that's a good sign."

Cr Perkins said the council's staff provided planning and development support for developers and credited them with achieving successful outcomes for the region.