The new road opened temporarily on Wednesday, but will close again on Thursday, according to the City of Ballarat's infrastructure and environment director Terry Demeo.

"There is a temporary intersection treatment proposed for the intersection of Gregory Street West and Gillies Street," he said in a statement.

"This treatment will ban right turns into Gregory Street West to ensure that this intersection remains safe in the interim prior to the installation of the full signalised treatment under the Regional Roads Victoria Keeping Ballarat Moving program.

"It is expected that this temporary treatment will be in place until mid to late January, which will allow Gregory Street to be opened through to the Ring Road."

The Ring Road entrance to Gregory Street West will also close in late January or early February, to upgrade the connection from the Ballarat Link Road.

The traffic lights on Gillies Street are one of several intersection improvements under way across the city, funded by the state government.

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