Council is to call for tenders to build a bridge across the Dog and Duck floodway on Wirrinya Road.

Backed by funding under the NSW Government’s Central West Recovery and Resilience Package, Forbes Shire Council has been looking at options for a new bridge over the floodway.

Councillors have now supported a move to go to tender for both a six and a seven-span bridge, with the design to be finalised once tenders come in.

The proposal is for a bridge deck four to five metres above the creek bed - which would improve access during more frequent flood events but not completely flood-proofing it.

Council staff looked at a number of options for the floodway - currently a concrete causeway on Wirrinya Road some 9km south of Forbes - the council's director infrastructure and works Dan Speer said in his report to councillors' May meeting.

Hydraulic assessment of those options shows that the number of spans across the Bundaburrah Creek would have a big influence on upstream flow levels and flow velocities.

A six-span bridge - about 90m - would span approximately 70 per cent of the 130m wide Bundaburrah Creek floodway channel at the crossing.

"The three span option results in materially higher upstream afflux and significantly increased flow velocities through the bridge opening when compared with the six span and nine span options, particularly for more frequent flood events," Mr Speer's report said.

"The six span bridge provides a materially wider effective waterway, resulting in lower upstream flood impacts and substantially reduced velocity and scour risk when compared with the three span option, while remaining more proportionate and cost-effective than the nine span option."

The project is currently progressing through planning and design.

The final scope, costs and construction timing will be confirmed following the tender phase.

The bridge is one of the projects to gain a share of the $32 million regional transport resilience fund, shared across Cabonne, Forbes, Parkes and Lachlan local government areas as part of the NSW Government's central west recovery and resilience package.