Big wet causes flooding and slip chaos | Manawatu-Wanganui News | Local News in Manawatu-Wanganui

The heavy rain that swamped the Wanganui district yesterday created a major headache for authorities, with a number of roads closed by slips and surface flooding.

The biggest problems occurred on SH3, south of the city, with slips and flooding causing major traffic bottlenecks, prompting police to divert traffic for much of the afternoon.

The Wanganui District Council's weather station recorded 35mm of rain falling on the city during a seven-hour period from 5am yesterday.

The worst of the slips occurred on the Ratana Hill passing lanes, with the bank above the highway coming down in a number of places. Contractors worked for a large part of the day cleaning away the spoil. It was here that the traffic snarl-ups happened.

In the Marybank area, south of the city, streams burst their banks and water backed up until it flooded SH3 just south of the airport roundabout. When that happened, police had no option but to close the road between Wikitoria Rd and Warrengate Rd, diverting main highway traffic along No 2 Line through Fordell.

But once beyond that diversion, motorists had to contend with major delays between Whangaehu and Ratana on SH3. At one stage, southbound traffic had backed up from the bottom of the Ratana hill to the Whanganui River bridge.

A large slip also came down on SH3 near the Kaitoke Rd turnoff.

Pupils at Turakina School were sent home early with concerns that surface flooding would prove a problem later in the day.

And diversions were in place on SH1 at Blue Gum Corner, near Marton, when surface water blocked that road. Traffic was diverted through Marton Junction.

There was also some surface flooding around the Rangitikei town, including at James Wilson Park. The level of the Tutaenui Stream, which flows through the town, rose menacingly and by mid-afternoon homes on its bank had an anxious wait before waters receded.

It was not just the state highway that copped it. A number of Wanganui's rural roads were affected and the city's stormwater system was working near capacity to divert rainwater into pumping stations.

Julian Reweti, the council's infrastructure manager, said both stormwater pipes and the Beach Rd pumping station worked "flat out" handling the fallout.

Mr Reweti said council staff had inspected sumps and drains across the city and cleared a number of blocked sumps. There was some minor surface flooding in the Castlecliff area and some minor slips elsewhere.

Putiki had some sewer blockages and stormwater had backed up for a time. The Matarawa Stream reached a high level and the diversion system there had been working at maximum capacity.

Both Hipango Tce and Georgetti Rd were down to one lane overnight because of slips.

Roberts Ave in Aramoho was closed overnight after a power line slipped due to the big wet. Tenix crews were working through the night to repair the damage and restore power.

That power outage also had an impact on television viewing as the city lost its free-to-air TV signal from yesterday afternoon.

"The city area generally coped with the rainfall, which we're expecting to ease later today and clear by Wednesday," Mr Reweti said.

But he said the rural areas remained a concern.

"The ground is saturated, and it's likely there will be further slips and flooding in some rural areas."

Two roads, Tokomaru West and Kaukatea Valley, remained closed overnight due to slips. Flooding closed Kauarapaoara Rd and Okoia Rd but both reopened early in the evening.

Mr Reweti said Longacre Rd was closed from Thompson Rd to normal traffic until this morning.

At Mowhanau village, some residents reported stormwater spilling through their properties on Peat Ave.

It was believed the water was coming from a part of the hillside hit by slipping recently.

Mr Reweti said council officers received more than 100 calls about drainage problems and staff were working into the evening to assess as many of these as possible.

Levels in the Whanganui, Whangaehu and Turakina rivers rose but none had reached threatening levels last night. The Whanganui was expected to peak about 7.5m at Pipiriki around 11pm last night.

Horizons Regional Council was keeping a close eye on river levels, but the worst of the flooding appears to have occurred in the Horowhenua and Tararua.

Allan Cook, Horizons emergency manager, said they were expecting up to 100mm more rain to fall in the Tararuas and between 60-80mm in the Ruahines throughout yesterday afternoon, which prompted the council to open the Motoa flood gates on the Manawatu River.