The rising Kauearanga River has meant there is no access into Thames, while debris and flooding litter the Thames Coast Rd.
Motorists are being urged to avoid the area and stay at home as the weather continues to worsen.
The Waikato Regional Council said the road is now a spillway for floodwaters.
The Karangahake Gorge which runs from Waihi to Paeroa was briefly closed after a blocked culvert began to flood.
However, NZ Transport Agency's Natalie Mankelow said the flooding did not last long and the section of State Highway 2 was re-opened.
She urged motorists to take extra care while driving.
Pauanui resident Michelle Dellabarca said she hasn't seen flooding so bad in her area during the whole 15 years she's lived there.
A Thames-Coromandel District Council spokesperson urged residents not to drive anywhere as there were many road closures and those not closed likely had debris on them which was being cleared by local firefighters.
"Whangamata, Tairua, Pauanui, there's a lot of flooding, there's no way of getting in or out of there at the moment.
"Even trying to get from Whangamata to Thames, even coming into Thames from the Plains. There's a lot of flooding and debris on the road."
The Thames Coast Rd is littered with debris and between Thames and Coromandel town and unable to be accessed.
Civil Defence centres have been set up in the Pauanui Community Centre, the Whangamata Town Hall and those in Thames can head to the council building.
Wastewater services in Whangamata were also under pressure.
"So don't flush if you don't need to," she said.
The council initially reported the town was out of petrol; however, Z Energy has confirmed their station in Whangamata had petrol but the Eftpos wasn't working.
Several schools were also closed for the day.
