Waka Kotahi NZ Transport Agency said the route was the most practical option to accommodate heavy vehicles and further tweaks to traffic management were likely.
The detour, along Gladfield Rd and Gladstone Rd South, is expected to be in place for a month as work is undertaken in the Dunedin-bound lane of Main South Rd (State Highway 1).
Mosgiel Taieri Community Board chairman Andrew Simms said the board was "pretty disappointed" with how the detour through Gladfield and Gladstone Rds had gone since it was put in place on Tuesday.
Yesterday, there was another long queue of traffic down Gladstone Rd South from the intersection with Quarry Rd (State Highway 87) at 11.15am, Mr Simms said.
On Wednesday, some drivers reported delays of up to 30 minutes.
In consultations before the detour was put in place, the board had raised issues with the short amount of time which the right-hand-turn lights into Quarry Rd were green, which had caused gridlocks at peak times during diversions in previous years.
Later that morning, Mr Simms recorded the right-turn signal lasting for 15 seconds.
While Dunedin-bound traffic in Gordon Rd was able to divert via Three Mile Hill Rd, those stuck in Gladstone Rd had no option but to sit there, he said.
"People are making their own detours, which is great, but I think the more we encourage that the better," Mr Simms said.
He suggested commuters from the south should consider using Law Rd through to Green Island, and those travelling between Mosgiel and Dunedin should use Three Mile Hill Rd.
The board had also raised concerns about the risk to children from heightened amounts of traffic in the area, Mr Simms said.
East Taieri School principal Jennifer Horgan said Wednesday had been challenging but things were much better yesterday.
Downers had been responsive to feedback and had rostered on extra staff to assist with road crossings in the mornings and afternoons, Ms Horgan said.
A transport agency spokesman said the current detour had been put in place as the best option for all traffic, including heavy vehicles.
While passenger cars could use alternative routes, it was not practical to signpost all possible alternatives - which could result in heavy vehicles using detour routes that might put other road users at risk and result in fines for operators.
The only other detour suitable for all traffic was through Outram, which would be longer and still pass through the intersection of Gladstone and Quarry Rds.
The agency was monitoring traffic volumes and making adjustments to ensure optimal timing on the traffic lights.
While the lights had been operating on fixed timings, changes were made yesterday morning to better respond to traffic volumes and more minor adjustments were likely, the spokesman said.
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