The bridge will be closed for six months from February 14 for a $9.6 million upgrade to allow heavy vehicles to cross over the bridge.

In the meantime, vehicles accessing Bomen and North Wagga will be detoured via Wagga until August 1.

Wagga City Council's project manager Silas Darby said Eunony Bridge currently carried 3430 vehicles each day, about 12.5 per cent of which were heavy vehicles.

Although the majority detoured will be passenger vehicles, Mr Darby said there will be an additional 3000 trucks travelling on Edward Street each week once construction is under way.

"If I said to you that wouldn't cause some degree of inconvenience for the people of Wagga, I'd be lying," he said.

The council anticipates congestion at the roundabout connecting the Olympic and Sturt highways, but Mr Darby said these hold-ups will happen in the early morning and late afternoon when truck movements are more frequent.

"I do foresee there being increased traffic hold-ups at the ... intersection," he said.

"I would suggest passenger vehicles [avoid that area] in the late afternoon. I know some can't and yes, there will be some inconveniences."

He said congestion on the Gobbagombalin Bridge was not expected to become a major issue.

Despite thousands of extra road users each day, Mr Darby said there are no concerns for safety, granted that people adhere to speed limits and rules.

"Obviously people might become impatient, which is potentially problematic, but we just ask people to hold it in and accept that in order to make these improvements, which we do need to make, we've got to do something substantial," he said.

After the strengthening and widening works are complete, Mr Darby said the bridge will be able to carry vehicles of 160 tonnes and 25 metres.

He said once the RiFL Hub opens, the number of vehicles crossing the bridge each day is expected to double in five years.