Rotorua’s wastewater system was “unable to cope at several points” during last night’s heavy rain resulting in overflow into Lake Rotorua.

The city bore the brunt of Tuesday’s intense rainfall with authorities warning of fresh slips and potholes this morning.

“Due to the heavy rain and the very high water levels of the lakes and groundwater table, stormwater caused excessively high inflows to the Rotorua wastewater system which was unable to cope at several points last night,” Rotorua Lakes Council said in a statement today.

“Issues included wastewater overflowing into a stormwater drain leading to Sulphur Bay for several hours in the early evening and fully treated effluent overflowed from the holding ponds at the Rotorua WWTP [wastewater treatment plant] to the Puarenga Stream for a period in the late evening.”

A car in floodwaters on Totara St in Rotorua on Tuesday. Photo / Supplied

“Council and its contractors worked throughout the night to minimise the impact of this and reported to BOPRC, mana whenua and other stakeholders about what was happening.”

Other network overflows occurred at Depot St, Lake Rd and Victoria St, and a wastewater pump station at Tikitere became blocked with rags, combined with high flows, caused an overflow to land.

The blockage has since been fixed.

114mm of rain in 24 hours

Weather warnings were due to be lifted for the region early Wednesday but more rain was forecast for today.

Metservice duty meteorologist Mmaphapelo Makgabutlane said Rotorua had received 114mm of rain in 24 hours up to 6am today.

“In a typical May, Rotorua would get around 142mm,” Makgabutlane said.

Galatea recorded 92mm of rain in the same time period.

Major slip between Moose Lodge and Ruato Bay on State Highway 30. Photo/ Andrew Warner

The heaviest rainfall in Rotorua occurred between 4pm and 5pm yesterday when 44mm fell in the one hour. The hour before that 20mm fell.

“Some places got a huge dumping of rain,” Makgabutlane said.

Metservice’s station at Tauranga Airport had measured about 71mm of rain while across the Coromandel 50mm to 60mm of rainfall was recorded with 78mm of rain recorded at Metservice’s Goldcross station.

Road information

Waka Kotahi NZ Transport Agency advises that due to high river levels, State Highway 2 Pekatahi Bridge has been closed.

“The river is approximately 600mm below the bridge deck.

“With more water collecting from the hills, the decision has been made to close the bridge for safety reasons until the water subsides.

“The detour for northbound traffic is through Tāneatua Rd, Arawa Rd, Hinemoa St and State Highway 30 towards Awakeri. Southbound traffic will use the same route, in reverse.”

Surface flooding on Fairy Springs Rd.

Meanwhile, SH36, between Jackson and Central Rd is closed as was Hamurana Rd, between Mourea and Unsworth Rd, where crews were clearing large rocks and logs.

SH2 is closed at Maniatutu, between the Tauranga Eastern Link and Pikowai Beach, due to flooding at the Kaikokopu Stream Bridge. A short detour is in place via Paengaroa.

SH30 between Tiketere and Rotoma was affected by multiple slips with temporary traffic management in place.

Due to flooding at Kaikokopu Stream Bridge, SH2 is closed between Wilson Rd and Maniatutu Rd. A detour is in place.

Rotorua Lakes Council said crews were inspecting areas in Ngakuru, Rerewhakaaitu, Reporoa and around Spencer Rd this morning and contractors were repairing potholes in urban areas.

Bay of Plenty Civil Defence says new potholes are likely to have formed overnight after the wet weather and motorists should watch their speed.

It asked people to plan their journey and expect delays given the several road closures, including state highways.

High water level at Lake Rotoma. Photo / Andrew Warner

It said the heavy rain warning had passed but people needed to be aware there could be surface flooding in areas, especially those low-lying.

Bay of Plenty Regional Council said all major rivers were expected to reach warning level one, with some also reaching warning level two. Landowners in affected areas were being notified to move stock from low-lying areas.

The regional council said many of the district’s streams had risen significantly as had the lakes, some by at least 100mm.

More to come.