NZ Historic Weather Events Catalogue
May 2005 Bay of Plenty and Waikato Flooding
(
2005-05-18
)
Phenomenal, unprecented high rainfall affected the Bay of Plenty especially in the Tauranga and Matata areas. Landslides and flooding caused much damage to buildings and property. Matata was hit by devastating debris flows.
Waikato
Heavy Rain
at
Waikato
There was very high intensity rainfall across the Coromandel Peninsula on the 18th and 19th of May which caused localised flooding. The rainfall was mostly coastal.
It was thought that hourly intensities were greater than 100 mm (10.0 cm) an hour at Hikuai, Pauanui, Whangamata and Opoutere.
Eight people were killed in a bus/truck crash in the Waikato during heavy rain on the 18th.
Flooding
Kopu-Hikuai Road was closed for a short period.
Eastern areas of Coromandel Peninsula were cut off and roads were rendered impassable.
Heavy Rain
at
Castle Rock
Castle Rock recorded 78mm (7.8 cm) of rain in 24 hours.
Heavy Rain
at
Golden Cross
Golden Cross recorded 148 mm (14.8 cm) of rain in 24 hours.
Heavy Rain
at
Hikuai
Hikuai recorded 300 mm (30.0 cm) of rain in 24 hours (which has a 30 year return period).
Hikuai recorded 900 mm (90.0 cm) of rain in 72 hours (which has a return period of over 150 years).
Flooding
The Tangitarori Stream culvert on Hikuai Settlement Road completely blew out, leaving the road impassable for almost 24 hours.
Hikuai Stream overflowed its banks destroying fences and blocking SH25.
Heavy Rain
at
Pauanui
Pauanui recorded 138 mm (13.8 cm) of rain in 24 hours.
Heavy Rain
at
The Pinnacles
The Pinnacles recorded 220 mm (22.0 cm) of rain in 24 hours.
Heavy Rain
at
Whangamata
Whangamata recorded 278 mm (27.8 cm) of rain in 24 hours (which has a 50 year return period).
Flooding
Waikiekie Stream in Whangamata overflowed its banks and inundated about five homes.
Wentworth River overflowed its banks and inundated properties.
Heavy Rain
at
Whitianga
Whitianga recorded 260 mm (26.0 cm) of rain in 24 hours (which has a 50 year return period).
Flooding
Te Weite Stream near Whitianga blocked SH25 twice in two days.
Bay of Plenty
Heavy Rain
at
Bay of Plenty
Duration: 2 days - Phenomenal, unprecented high rainfall affected the Bay of Plenty on the 18th and 19th of May especially in the Tauranga and Matata areas.
A shallow low brought warm, moist, unstable air down onto the Bay of Plenty. Convergence zones within the airstream produced high hourly rainfall intensities. One stalled over Tauranga for a time. It was likely that another convergence zone produced the downpour in hills above Matata that night. A high-pressure system to the south of the country was blocking the low from moving.
Multi Hazard
156 homes were uninhabitable after the floods and landslides.
State Highway 2 was closed.
Flooding
Flooding was localised and was generally surface flooding.
It was estimated that 1 in 5 of the flood victims had no insurance cover.
There was surface flooding at Pongakawa, Awakaponga and the Rangitaiki Plains.
Children were trapped in schools and one family was trapped on a house roof.
The cost of damage was estimated at $40-$50 million ($45,626,000-$57,033,000 2010 dollars).
The total insurance payout was $30 million ($34,220,000 2010 dollars).
Heavy Rain
at
Awakaponga
Awakaponga recorded 94.5 mm (9.45 cm) of rain in one hour (which has over a 150 year return period.
Awakaponga recorded 150 mm (15.0 cm) of rain.
Flooding
at
Edgecumbe
There was some flooding in Edgecumbe.
Heavy Rain
at
Matata
More than 300 mm (30.0 cm) of rain hit Matata in 24 hours.
Flooding
A torrential downpour in the hills in the catchment above Matata, turned small streams into raging torrents and swept down carrying logs, huge boulders and river silt. The heavy rain triggered many landslips, leading to large debris flows, with associated flooding which caused much destruction. The intense rainfall fell in a narrow band only a few kilometres wide which passed across the catchment to the south of Matata from near the mouth of Ohinekoao Stream to Awakapongo.
Rainfall was approximately a 500 year recurrance event, and the associated debris flows may have the same recurrance interval. Historical records indicate that smaller events have occurred in the area since 1860.
A state of emergency was declared in small township of Matata near Whakatane due to serious flooding.
Debris flows wiped out houses, roads and a wild life reserve and littered the town with silt and natural and manmade debris.
Houses and vehicles were buried under up to five metres of silt and 14 cars were left bobbing in the lagoon. Two houses and eight to nine caravans from the campng ground were swept out to sea. Three houses were pushed off their foundations, garages were wrecked and acres of land was buried by silt.
538 people were evacuated from Matata. People were evacuated to Whakatane.
A number of houses were underwater or hit by mudslides. Debris flows caused the destruction of 27 homes and damage to 87 properties. Owners of 31 Matata properties were told that their homes would not be rebuilt.
An estimated 700,000 cubic metres of debris, ranging from silt to large boulders and trees, was deposited in and around Matata and the Matata lagoon.
There was extensive damage to local roads. Parts of roads and two bridges across State Highway 2 were washed away. State Highway 2 to the west and east of Matata was closed.
There was significant damage to the railway line at a number of points in and around Matata and the line was closed.
Rural land was flooded.
There was disruption and damage to water and electricity supplies. There was damage to storm water and septic tank sewerage disposal systems.
The wildlife refuge with two lagoons bordering the beach was severely damaged. Debris filled 60 percent of the two lagoons with silt, boulders, logs and household items, including cars. The Department of Conservation estimated the cost of restoring the west lagoon at $800,000 ($912,500 2010 dollars).
Debris flows were the direct consequences of landslips triggered by exceptionally heavy rains. Debris flows caused the damage to Matata in the vicinity of Awataraiki and Waitepuru Streams. Boulders up to seven metres in diameter were moved by Awatarariki Stream debris flows. Debris floods damaged property in the vicinity of Waimea Stream. The Ohinekoao Stream debris flow reached State Highway 2.
Landslide
at
Mount Maunganui
Four slips around the base of Mount Maunganui closed the walking track and broke a major water main.
Flooding
at
Papamoa
Over 40 houses in Papamoa were evacuated.
The army evacuated a motor camp in Papamoa, with up to 100 residents affected.
Heavy Rain
at
Pongakawa
Pongakawa recorded 170 mm (17.0 cm) of rain.
Heavy Rain
at
Tauranga
Tauranga airport recorded 217 mm (21.7 cm) of rain in 12 hours (which has a 150 year return period).
Tauranga airport recorded 133 mm (13.3 cm) of rain in three hours (which has over a 150 year return period).
Tauranga Airport recorded 346.8 mm (34.68 cm) of rain in two days.
Up to the 20th May Tauranga have received 557 mm (55.7 cm) of rain.
Multi Hazard
A state of emergency was declared in Tauranga.
63 people mainly elderly were evacuated from Otumoetai.
Numerous vehicles were stranded in Welcome Bay.
Schools were closed.
400 people were evacuated from Tauranga, Mount Maunganui and Papamoa and and by October 82 households were still living in temporary accomodation.
By October 2005 more than 2000 insurance claims had been made and 625 accepted by the Earthquake Commission.
Several city houses were destroyed mudslides and floodwaters. The downpour caused widespread damage to homes at Pillans Point, Otumoetai, Welcome Bay and Mt Maunganui. The worst hit suburbs were Otumoetai (flooding and slips in streets including Vale St, Landscape Rd, Himewa Rd, Whittaker St and Pillans Rd) and Welcome Bay (Estuary View Rd, Corinna St and Dingadee St).
The disaster affected 789 properties. In the aftermath of the disaster, the council carried out inspections of 1067 homes and properties. 39 houses were deemed total losses and 12 had already been demolished or transported to other sites.
Flooding
Police, Fire, Army and other emergency services were stretched to the limit due to heavy rain and flooding.
It was the fourth time in five years that the area was hit by severe flooding.
Floodwaters damaged roads and railway lines near Mt Maunganui and Welcome Bay.
The airport was closed by flooding.
Landslide
Landslides threatened several homes and massive slips caused houses to collapse. Houses in Shelley Street, Landscape Road, Vale Street and Whittaker Street were badly affected.
Slips covered railway lines and disrupted rail traffic.
A report found that the primary cause of the slips was "overland flow due to the extreme rain event".
Heavy Rain
at
Te Puke
Te Puke recorded 187 mm (18.7 cm) of rain.
Heavy Rain
at
Whakatane
Whakatane airport recorded 127 mm (12.7 cm) of rain.
References
- Daily Post (Rotorua) Flood hit town's residents face huge rates hike 08/12/05
- Picture: Matata was devastated by the May flood
- Earthquake Commission
- Environment Waikato Flood Document (CD)
- Institute of Geological and Nuclear Sciences limited , The 18 May 2005 Debris - flow Disaster at Matata
- Insurance Councils, The Cost of Weather Loses, Claims history (Updated 2004)
- Major weather events in New Zealand, FLOODS and HIGH RAINFALL, Floods to 30 Sep 2005
- Matata Business Case
- Meteorological Society of New Zealand (Inc.) Newsletter 101, June 2005.
- Meteorological Society Of New Zealand (Inc.) September 2006 Report.
- Headline: Flood victims told they can never go home.
- New Zealand Herald, Juliet Rowan, 13 July 2005. Picture: Heavy overnight rain brought more chaos for Paul's Beach home, which was moved off its foundations in May's flood Alan Gibson
- Headline: Matata: The perfect disaster.
- New Zealand Herald, Juliet Rowan, 18 June 2005 Picture: Wayne Maloney calculates that this stream went from 10cm to 10m deep in 30 seconfs Alan Gibson
- Headline: Matata: Flood-hit town gets $3m from Government for rebuilding.
- New Zealand Herald, Juliet Rowan, 20 December 2005.
- NZ Met Service. (2008). Meteorology of Extreme Rainfalls in New Zealand (Mark Pascoe, Ed.).
- Headline: Slips cause houses to collapse.
- TVNZ, 18 May 2005.
- Headline: Flood-hit properties to be recorded.
- www.nzherald.co.nz, 04 October 2005.
- Headline: State of emergency in Tauranga.
- www.nzherald.co.nz, 18 May 2005.
- Headline: Heartbreak as landslide reduces new home to pile of rubble.
- www.nzherald.co.nz, 19 May 2005.
- Headline: Hundreds of people evacuated as more downpours forecast.
- www.nzherald.co.nz, 19 May 2005.
- Headline: More evacuations in flood ravaged Bay of Plenty.
- www.nzherald.co.nz, 19 May 2005.
- Headline: Rescuers' relentless fight against deluge.
- www.nzherald.co.nz, 19 May 2005.
- Headline: My home floated down the street.
- www.nzherald.co.nz, 20 May 2005.
- Headline: Flood hit town "will never be the same".
- www.nzherald.co.nz, 21 November 2005.
- Headline: Bay of Plenty Flood - Flood's litany of destruction and expense.
- www.nzherald.co.nz, 24 May 2005.
- Headline: Flood hits many without insurance.
- www.nzherald.co.nz, 27 May 2005.
- Headline: Tauranga stormwater upgrade to cost $52 m.
- www.nzherald.co.nz, Juliet Rowan, 12 October 2005,
- Headline: Bay of Plenty residents bracing themselves for more rain.
- www.nzherald.co.nz, Source: NZPA, 21 May 2005.
- Headline: More rain for flood-ravaged BOP.
- www.stuff.co.nz, 19 May 2005. Bay of Plenty : many pictures included
- Headline: Owner flees as bank collapses.
- www.stuff.co.nz, 19 May 2005.
- www.thunderstorm.co.nz
- Folder: O:\RRMG052\RawData\Photos 2 file\www.thunderstorm.co.nz - 12 Photos of BOP flooding (taken on 21/05/2005)
May 2005 Bay of Plenty and Waikato Flooding
(
2005-05-18
)
Phenomenal, unprecented high rainfall affected the Bay of Plenty especially in the Tauranga and Matata areas. Landslides and flooding caused much damage to buildings and property. Matata was hit by devastating debris flows.
Waikato
Heavy Rain
at
Waikato
There was very high intensity rainfall across the Coromandel Peninsula on the 18th and 19th of May which caused localised flooding. The rainfall was mostly coastal.
It was thought that hourly intensities were greater than 100 mm (10.0 cm) an hour at Hikuai, Pauanui, Whangamata and Opoutere.
Eight people were killed in a bus/truck crash in the Waikato during heavy rain on the 18th.
Flooding
Kopu-Hikuai Road was closed for a short period.
Eastern areas of Coromandel Peninsula were cut off and roads were rendered impassable.
Heavy Rain
at
Castle Rock
Castle Rock recorded 78mm (7.8 cm) of rain in 24 hours.
Heavy Rain
at
Golden Cross
Golden Cross recorded 148 mm (14.8 cm) of rain in 24 hours.
Heavy Rain
at
Hikuai
Hikuai recorded 300 mm (30.0 cm) of rain in 24 hours (which has a 30 year return period).
Hikuai recorded 900 mm (90.0 cm) of rain in 72 hours (which has a return period of over 150 years).
Flooding
The Tangitarori Stream culvert on Hikuai Settlement Road completely blew out, leaving the road impassable for almost 24 hours.
Hikuai Stream overflowed its banks destroying fences and blocking SH25.
Heavy Rain
at
Pauanui
Pauanui recorded 138 mm (13.8 cm) of rain in 24 hours.
Heavy Rain
at
The Pinnacles
The Pinnacles recorded 220 mm (22.0 cm) of rain in 24 hours.
Heavy Rain
at
Whangamata
Whangamata recorded 278 mm (27.8 cm) of rain in 24 hours (which has a 50 year return period).
Flooding
Waikiekie Stream in Whangamata overflowed its banks and inundated about five homes.
Wentworth River overflowed its banks and inundated properties.
Heavy Rain
at
Whitianga
Whitianga recorded 260 mm (26.0 cm) of rain in 24 hours (which has a 50 year return period).
Flooding
Te Weite Stream near Whitianga blocked SH25 twice in two days.
Bay of Plenty
Heavy Rain
at
Bay of Plenty
Duration: 2 days - Phenomenal, unprecented high rainfall affected the Bay of Plenty on the 18th and 19th of May especially in the Tauranga and Matata areas.
A shallow low brought warm, moist, unstable air down onto the Bay of Plenty. Convergence zones within the airstream produced high hourly rainfall intensities. One stalled over Tauranga for a time. It was likely that another convergence zone produced the downpour in hills above Matata that night. A high-pressure system to the south of the country was blocking the low from moving.
Multi Hazard
156 homes were uninhabitable after the floods and landslides.
State Highway 2 was closed.
Flooding
Flooding was localised and was generally surface flooding.
It was estimated that 1 in 5 of the flood victims had no insurance cover.
There was surface flooding at Pongakawa, Awakaponga and the Rangitaiki Plains.
Children were trapped in schools and one family was trapped on a house roof.
The cost of damage was estimated at $40-$50 million ($45,626,000-$57,033,000 2010 dollars).
The total insurance payout was $30 million ($34,220,000 2010 dollars).
Heavy Rain
at
Awakaponga
Awakaponga recorded 94.5 mm (9.45 cm) of rain in one hour (which has over a 150 year return period.
Awakaponga recorded 150 mm (15.0 cm) of rain.
Flooding
at
Edgecumbe
There was some flooding in Edgecumbe.
Heavy Rain
at
Matata
More than 300 mm (30.0 cm) of rain hit Matata in 24 hours.
Flooding
A torrential downpour in the hills in the catchment above Matata, turned small streams into raging torrents and swept down carrying logs, huge boulders and river silt. The heavy rain triggered many landslips, leading to large debris flows, with associated flooding which caused much destruction. The intense rainfall fell in a narrow band only a few kilometres wide which passed across the catchment to the south of Matata from near the mouth of Ohinekoao Stream to Awakapongo.
Rainfall was approximately a 500 year recurrance event, and the associated debris flows may have the same recurrance interval. Historical records indicate that smaller events have occurred in the area since 1860.
A state of emergency was declared in small township of Matata near Whakatane due to serious flooding.
Debris flows wiped out houses, roads and a wild life reserve and littered the town with silt and natural and manmade debris.
Houses and vehicles were buried under up to five metres of silt and 14 cars were left bobbing in the lagoon. Two houses and eight to nine caravans from the campng ground were swept out to sea. Three houses were pushed off their foundations, garages were wrecked and acres of land was buried by silt.
538 people were evacuated from Matata. People were evacuated to Whakatane.
A number of houses were underwater or hit by mudslides. Debris flows caused the destruction of 27 homes and damage to 87 properties. Owners of 31 Matata properties were told that their homes would not be rebuilt.
An estimated 700,000 cubic metres of debris, ranging from silt to large boulders and trees, was deposited in and around Matata and the Matata lagoon.
There was extensive damage to local roads. Parts of roads and two bridges across State Highway 2 were washed away. State Highway 2 to the west and east of Matata was closed.
There was significant damage to the railway line at a number of points in and around Matata and the line was closed.
Rural land was flooded.
There was disruption and damage to water and electricity supplies. There was damage to storm water and septic tank sewerage disposal systems.
The wildlife refuge with two lagoons bordering the beach was severely damaged. Debris filled 60 percent of the two lagoons with silt, boulders, logs and household items, including cars. The Department of Conservation estimated the cost of restoring the west lagoon at $800,000 ($912,500 2010 dollars).
Debris flows were the direct consequences of landslips triggered by exceptionally heavy rains. Debris flows caused the damage to Matata in the vicinity of Awataraiki and Waitepuru Streams. Boulders up to seven metres in diameter were moved by Awatarariki Stream debris flows. Debris floods damaged property in the vicinity of Waimea Stream. The Ohinekoao Stream debris flow reached State Highway 2.
Landslide
at
Mount Maunganui
Four slips around the base of Mount Maunganui closed the walking track and broke a major water main.
Flooding
at
Papamoa
Over 40 houses in Papamoa were evacuated.
The army evacuated a motor camp in Papamoa, with up to 100 residents affected.
Heavy Rain
at
Pongakawa
Pongakawa recorded 170 mm (17.0 cm) of rain.
Heavy Rain
at
Tauranga
Tauranga airport recorded 217 mm (21.7 cm) of rain in 12 hours (which has a 150 year return period).
Tauranga airport recorded 133 mm (13.3 cm) of rain in three hours (which has over a 150 year return period).
Tauranga Airport recorded 346.8 mm (34.68 cm) of rain in two days.
Up to the 20th May Tauranga have received 557 mm (55.7 cm) of rain.
Multi Hazard
A state of emergency was declared in Tauranga.
63 people mainly elderly were evacuated from Otumoetai.
Numerous vehicles were stranded in Welcome Bay.
Schools were closed.
400 people were evacuated from Tauranga, Mount Maunganui and Papamoa and and by October 82 households were still living in temporary accomodation.
By October 2005 more than 2000 insurance claims had been made and 625 accepted by the Earthquake Commission.
Several city houses were destroyed mudslides and floodwaters. The downpour caused widespread damage to homes at Pillans Point, Otumoetai, Welcome Bay and Mt Maunganui. The worst hit suburbs were Otumoetai (flooding and slips in streets including Vale St, Landscape Rd, Himewa Rd, Whittaker St and Pillans Rd) and Welcome Bay (Estuary View Rd, Corinna St and Dingadee St).
The disaster affected 789 properties. In the aftermath of the disaster, the council carried out inspections of 1067 homes and properties. 39 houses were deemed total losses and 12 had already been demolished or transported to other sites.
Flooding
Police, Fire, Army and other emergency services were stretched to the limit due to heavy rain and flooding.
It was the fourth time in five years that the area was hit by severe flooding.
Floodwaters damaged roads and railway lines near Mt Maunganui and Welcome Bay.
The airport was closed by flooding.
Landslide
Landslides threatened several homes and massive slips caused houses to collapse. Houses in Shelley Street, Landscape Road, Vale Street and Whittaker Street were badly affected.
Slips covered railway lines and disrupted rail traffic.
A report found that the primary cause of the slips was "overland flow due to the extreme rain event".
Heavy Rain
at
Te Puke
Te Puke recorded 187 mm (18.7 cm) of rain.
Heavy Rain
at
Whakatane
Whakatane airport recorded 127 mm (12.7 cm) of rain.
References
- Daily Post (Rotorua) Flood hit town's residents face huge rates hike 08/12/05
- Picture: Matata was devastated by the May flood
- Earthquake Commission
- Environment Waikato Flood Document (CD)
- Institute of Geological and Nuclear Sciences limited , The 18 May 2005 Debris - flow Disaster at Matata
- Insurance Councils, The Cost of Weather Loses, Claims history (Updated 2004)
- Major weather events in New Zealand, FLOODS and HIGH RAINFALL, Floods to 30 Sep 2005
- Matata Business Case
- Meteorological Society of New Zealand (Inc.) Newsletter 101, June 2005.
- Meteorological Society Of New Zealand (Inc.) September 2006 Report.
- Headline: Flood victims told they can never go home.
- New Zealand Herald, Juliet Rowan, 13 July 2005. Picture: Heavy overnight rain brought more chaos for Paul's Beach home, which was moved off its foundations in May's flood Alan Gibson
- Headline: Matata: The perfect disaster.
- New Zealand Herald, Juliet Rowan, 18 June 2005 Picture: Wayne Maloney calculates that this stream went from 10cm to 10m deep in 30 seconfs Alan Gibson
- Headline: Matata: Flood-hit town gets $3m from Government for rebuilding.
- New Zealand Herald, Juliet Rowan, 20 December 2005.
- NZ Met Service. (2008). Meteorology of Extreme Rainfalls in New Zealand (Mark Pascoe, Ed.).
- Headline: Slips cause houses to collapse.
- TVNZ, 18 May 2005.
- Headline: Flood-hit properties to be recorded.
- www.nzherald.co.nz, 04 October 2005.
- Headline: State of emergency in Tauranga.
- www.nzherald.co.nz, 18 May 2005.
- Headline: Heartbreak as landslide reduces new home to pile of rubble.
- www.nzherald.co.nz, 19 May 2005.
- Headline: Hundreds of people evacuated as more downpours forecast.
- www.nzherald.co.nz, 19 May 2005.
- Headline: More evacuations in flood ravaged Bay of Plenty.
- www.nzherald.co.nz, 19 May 2005.
- Headline: Rescuers' relentless fight against deluge.
- www.nzherald.co.nz, 19 May 2005.
- Headline: My home floated down the street.
- www.nzherald.co.nz, 20 May 2005.
- Headline: Flood hit town "will never be the same".
- www.nzherald.co.nz, 21 November 2005.
- Headline: Bay of Plenty Flood - Flood's litany of destruction and expense.
- www.nzherald.co.nz, 24 May 2005.
- Headline: Flood hits many without insurance.
- www.nzherald.co.nz, 27 May 2005.
- Headline: Tauranga stormwater upgrade to cost $52 m.
- www.nzherald.co.nz, Juliet Rowan, 12 October 2005,
- Headline: Bay of Plenty residents bracing themselves for more rain.
- www.nzherald.co.nz, Source: NZPA, 21 May 2005.
- Headline: More rain for flood-ravaged BOP.
- www.stuff.co.nz, 19 May 2005. Bay of Plenty : many pictures included
- Headline: Owner flees as bank collapses.
- www.stuff.co.nz, 19 May 2005.
- www.thunderstorm.co.nz
- Folder: O:\RRMG052\RawData\Photos 2 file\www.thunderstorm.co.nz - 12 Photos of BOP flooding (taken on 21/05/2005)