UPDATE 11AM: Both lanes along State Highway 29 in the lower Kaimais are now open after a slip blocked a portion of the highway earlier today.

Motorists driving over the Kaimais this morning are being warned to drive carefully as heavy rain continues in the Tauranga and Western Bay of Plenty.

A slip is blocking part of State Highway 29 on the Kaimais.

NZ Transport Agency says both lanes are still open along State Highway 29 east of the Kaimai's near Tuakopai Stream bridge despite a small slip over night.

NZTA highways manager Brett Gliddon says the road is open to two lanes with a speed restriction in place to allow workers to clear up the slip material.

Brett says the slip was small and they expect to clear the slip material by 4pm today.

'Traffic is flowing through the area, there is a 30km/h temporary speed limit which should be removed once the area is cleared," says Brett.

'There are no reported delays.”