THE boss of one of Queensland's best-known builders has slammed council works on one of Brisbane's busiest streets, while acknowledging it is inevitable.

Upgrades of a drain along James St has seen lanes from Ann St closed and traffic diversions put in place along the precinct and adjoining McLachlan St.

The diversions, which were established in June and are scheduled to finish by November, have seen concrete barricades erected in front of several businesses, including Lexus Brisbane and David Jones, with signs reminding customers that outlets remain open.

Hutchinson Builders chairman Scott Hutchinson, whose business owns the complex next to the site, said the project came at a time just after James St had been revitalised.

"It's a nightmare for the whole street," Mr Hutchinson told The Courier-Mail.

"We just finished construction on Calile, and the street is looking great and feeling great, then this happens."

Mr Hutchinson however said the project was for the greater good and "something we have to do."

"We were horrified when they told us it was going to happen, but we were given no choice," he said.

The Courier-Mail approached a half-dozen businesses in the vicinity of the works. Some said they had seen falls in foot traffic, which they couldn't directly attribute to the works.

One business had resorted to sending SMS alerts to customers with appointments, asking them to allow for extra travel time in order to find a park.

A spokeswoman for the James St Initiative however said the improvements had been well flagged and would benefit the community in the long-term.

The spokeswoman said upgrading to sewerage drains along James St aims to "improve drainage systems and increase future flood immunity for Fortitude Valley."

A Brisbane City Council spokeswoman said stakeholders had been consulted extensively and knew of the works ahead of construction.

"Access to local business has been maintained at all times and anyone impacted by the works has been provided with regular updates," the spokeswoman said.

"Throughout the works, there have been some lane and footpath closures for safety reasons, with traffic controllers and signage to safely direct motorists and pedestrians in place."

She said the project is slated to finish in November.