Heavy Rain - Nelson Rd
Localised flash floods washed a car down a creek and inundated several homes in Mangapapa and Riverdale this morning.
“It's been a rough morning,” a Tairāwhiti Civil Defence Facebook statement said.
“With the build-up of debris and silt in the waterways and the high water table, we have experienced flooding in some areas overnight.”
Widespread “severe” surface flooding happened around Mangapapa with 15 households self-evacuating to family, friends or the House of Breakthrough in Lytton West.
Tairāwhiti Civil Defence controller Phil Nickerson said roading crews were out at first light clearing drains and culverts.
“As well as the affected suburb of Mangapapa, it has been reported a bridge before Bushy Knoll turnoff in Tiniroto has been seriously damaged.
“The national State of Emergency for Hawke's Bay and this region has been extended for seven more days. This will give us time to continue our response to the impacts of Cyclone Gabrielle and this recent rain.”
The rain overnight has also resulted in State Highway 2 closing at Whatatutu at the Puha intersection.
SH35 is also closed between Ruatorea and Tikitiki due to a large slip near Tikitiki.
Flooding appeared worst around Clifford Street with floodwater going through several properties and even washing a car down a creek.
Nelson Road, Lytton Road, Oswald Street and Pilmer Road also experienced surface flooding.
MetService data shows Gisborne Airport experienced a dumping of 23.4mm in one hour from 3am, with 54mm recorded in the period between 3am and 7am today.
Gisborne District Council monitoring sites elsewhere in the city show about 100mm of rain fell in the past 24 hours (to 7am) across the city with 105mm recorded at Stout Street.
Some schools were forced to close for the day. Among them were Lytton High school, Kaiti School and Makaraka School. However, Mangapapa School, unlike some Mangapapa properties, came through unscathed and was able to open.
The weather also again closed the road to Opotiki, with a slip in the Waioeka Gorge closing SH2 between Opotiki and Puha.
Tiniroto Road was also closed by slips north and south of the Tiniroto settlement. There was also a large dropout on Lavenham Road and it's down to one lane.
MetService meteorologist Andrew James said the rainfall overnight was localised due to the nature of convective cells.
That meant 12-hour rainfall figures varied from 100mm in Wairoa to 66mm at Gisborne Airport, whilst another Gisborne monitoring site only recorded 30mm.
“It is the sort of thing that occurs in thunderstorms. Instead of it being driven by broadscale weather systems, it's happening on a very localised basis.
“So, these storms are small, compact systems, driven by upward motion. Terrain can influence them and they happen on a much smaller scale than seen in recent times.”
Fire and Emergency New Zealand started getting 111 calls about the flooding in Mangapapa at around 3.30am.
“We sent two crews into the suburb and assisted people in the catchment of the Mangapapa Stream,” said Senior Station Officer Peter Carroll.
“Along with police we checked on residents in the flooded areas and some were evacuated.”
The Character Roofing surf lifesaving emergency call-out squad was called out too with their IRBs.
“They checked on a resident at the top of Valley Road,” SSO Carroll said.
“As far as I know no one needed to be rescued, and fortunately the rain eased off in the nick of time.
“It also helped us that high tide was at 1am, so the tide was going out, flowing in our favour.
“Which was just as well because the Mangapapa Stream came up so quickly.”
SSO Carroll said he knows some houses had water through them.