NZ Transport Agency is advising people to allow around an extra 30 minutes for their journey while repairs are carried out on a tomo or sinkhole on State Highway 1 near Kinleith.

The tomo, which is around 1.5 metres deep and six metres long, has developed near the Mangaharekeke Bridge.

The road is closed between SH30 Ongaroto Rd and the SH30 Rotorua turn-off. People travelling from Tauranga and Rotorua are advised to consider using SH5 to Taupo.

Waikato Transport System Manager Karen Boyt says work is underway on the repair.

'Our contractors and geotechnical teams have moved quickly to keep people safe and start repairing the road. They will continue to work overnight so the road can be reopened as quickly as possible.

'Road users should check our website or call 0800 4 HIGHWAYS (0800 44 44 49) to see if the road is open before travelling,

'People should also drive carefully and to the conditions on the alternative route as it may be unfamiliar to some drivers."

Karen says the tomo is currently thought to have been caused by the stream eroding the bank abutting the bridge.

SH1 KINLEITH - WASHOUT - UPDATE 6:45AM
Due to a washout on Mangaharakeke Bridge #SH1 remains CLOSED currently between Ongaroto Rd (SH30 to Whakamaru) & the SH30 turn-off to Rotorua. Allow extra time for detours or delay your journey: https://t.co/PC6cjUCjhg ^TP pic.twitter.com/TrSO6u1qS5

— NZTA Waikato/BoP (@NZTAWaiBoP) November 22, 2018

Updates are available here: http://www.journeys.nzta.govt.nz/traffic/roadhazards/234362

Plan ahead for a safe, enjoyable journey. Keep up to date with:

· Traffic updates: nzta.govt.nz/traffic

· Facebook: facebook.com/NZTAWaikatoBoP

· Twitter: twitter.com/NZTAwaibop

· Journey planner: journeys.nzta.govt.nz

· Phone: 0800 4 HIGHWAYS (0800 44 44 49)