NZ Historic Weather Events Catalogue
April 1981 Waikato Storm
(
1981-04-11
)
50-64 years
Torrential rain and high winds struck the Thames-Coromandel area and inland to Paeroa. Paeroa and Thames suffered considerable flooding and over 2000 people were evacuated during the event. Half the town of Waikino was completely destroyed when Ohinemuri River flooded. A Civil Defence emergency was declared in the Paeroa Borough and Ohinemuri County and the Thames-Coromandel area.
North Island
Multi Hazard
at
North Island
Duration: 6 days - From the 11th to the 16th of April 1981.
Insurance industry payouts for the Thames, Coromandel and Paeroa floods amounted to $7,000,000 in 1981 ($26,042,000 2010 dollars).
The strong easterly air flow was caused by a deep depression north-west of North Cape and an anti-cyclone centred east of Christchurch.
There was no loss of life.
Auckland
Flooding
at
Auckland
Water from an overflowing culvert closed the main trunk line between Mercer and Tuakau on the 13th.
High Wind / Gust
at
Auckland City
Wind gusts of up to 61 knots (113 km/hr) were recorded in Auckland.
West Auckland was without electricity on the 13th and 14th. 34 major electricity feeders were put out of action in the Auckland Electric Power Board area, and 20 more in Franklin.
Power lines and trees were blown down.
Telephone services in Auckland were slightly impaired when several lines were broken in the wind.
Firemen were called out 120 times for pumping where roofs were blown off.
Maritime / Coastal
A section of the seawall at Mission Bay was collapsed.
11 boats, mostly large expensive yachts, were found on the 13th stranded on the rocks around the Auckland waterfront.
Flooding
at
Takapuna
There were some stormwater problems in Takapuna City.
High Wind / Gust
at
Waitemata Harbour
At least 30 boats went missing from the Waitemata Harbour.
Waikato
Heavy Rain
at
Waikato
There was torrential rain in Waikato on the 12th and 13th which caused flooding in the region.
Flooding
Between 7000 and 10,000 hectares of farmland between Paeroa and Thames was flooded.
The worst areas of flooding seemed to be around Paeroa, Thames, Waikino, Hikutaia, Wharepoa, Puriri and Matatoki. The floodwaters left a lot of silt on pastures.
Up to 2250 people were evacuated in the Thames, Paeroa and Waihi area.
Stock losses were minimal and were generally only young stock.
Rivers in high flood included the Te Puru, Tararu, Kaueranga, Kirikiri, Matatoki, Hikutaia, Komata, Waitoki, Mangaiti, Waiorongomai, Tairua, Ohinemuri.
It was the worst Coromandel flood on record to date and exceeded that of 1954 in severity and arial distribution of heavy rainfalls.
The main road from Auckland to the Bay of Plenty was flooded in the Pokeno valley and at Mangatawhiri. At that point farmland was completely submerged, with only the tops of fences and trees visible.
High Wind / Gust
Wind velocity was constant at 50 knots (92.6 km/hr).
One pleasure boat was sunk and several others broke loose from there moorings and were damaged during the gale on the eastern seaboard of the Coromandel Peninsula.
Gale force winds affected coastal areas.
Landslide
The Kopu-Hikuai Road was closed by slips in many places.
Hill country farmers suffered a lot from slips. The main effect of the slips has been to sweep away fencing.
Multi Hazard
The highway from Paeroa to Waihi was closed by slips and washouts.
Highway 25 south of Coroglen and south of Whangamata was closed on the night of the 12th as was Highway 2 between Paeroa and Waihi at Queen's Head.
Heavy Rain
at
Coromandel Range
The Coromandel Ranges received an estimated 850 mm (85.0 cm) of rain in 72 hours.
The Coromandel Ranges received an estimated 500+ mm (50.0 cm) of rain in 24 hours.
High Wind / Gust
at
Hahei
Strong winds blew off the roofs of six houses at Hahei and partially destroyed another home there.
Flooding
at
Hikutaia
Some residents had to be evacuated when floodwaters threatened their homes.
Flooding
at
Karangahake Gorge
In many parts of the Karangahake Gorge, road sealing had been ripped up and debris was scattered over the highway in many parts. The gorge road was finally opened back up on the morning of the 21st of April.
Heavy Rain
at
Kauaeranga River
Kauaeranga catchment received 870 mm (87.0 cm) of rain in 72 hours (which has a return period of over 150 years).
Kauaeranga catchment received 900 mm (90.0 cm) of rain during the storm event.
Heavy Rain
at
Ohinemuri River
Ohinemuri catchment received 700 mm (70.0 cm) of rain during the storm event.
Ohinemuri catchment received over 550 mm (55.0 cm) of rain from the 11th to the 12th.
Flooding
The river was running 10 metres or more than normal in places.
Flooding
at
Opoutere
Farmers at Opoutere were without power for a long period
Flooding of farmland was extensive in the area.
High Wind / Gust
at
Otama
One house was totally destroyed at Otama.
Heavy Rain
at
Paeroa
Paeroa recorded 197.9 mm (19.79 cm) of rain in 24 hours from the 12th to the 13th.
Paeroa recorded 375.8 mm (37.58 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of over 100 years).
Paeroa recorded 346.5 mm (34.65 cm) of rain in 48 hours (which has a return period of 90 years).
Flooding
A Civil Defence emergency was declared in the Paeroa Borough and Ohinemuri County from 5:39pm on the 12th to the 21st of April.
The Paeroa area received approximately 400 mm (40.0 cm) during the storm.
All businesses were closed.
Schools were closed.
Dozens of men piled more than 15,000 sandbags against a stopbank of the Ohinemuri River on the night of the 12th. Sandbags were also used to build dams around shops.
The main street and some side streets were under several centimetres of water.
The Ohinemuri River was running about 4 metres above its usual level and was lapping at the edge of the Criterion Bridge leading into town.
There was a major evacuation of town. Low-lying residences and businesses were evacuated. More than 1000 people were evacuated in the Paeroa district.
The district's highways and roads were battered into closure. Roads to Waihi, Thames and State Highway 2 to Auckland were cut.
In 24 to 36 hours the Ohinemuri River, which flows through Paeroa, flooded twice.
Paeroa's main pipeline was broken in a number of places and people were told to use water sparingly. Fresh water supplies became polluted with brown floodwaters.
Sewage from the town's outfall was floating in the floodwaters, creating a health hazard. All furnishings and household effects were contaminated.
A large part of the town was underwater.
Air Force Helicopters were used to check the safety of families in outlying valleys and drop food to them.
The flooding was caused by the overtopping and breaching of ageing stopbanks along the Ohinemuri River west of town, and by the overflow from recently canalised tributary streams that traverse Paeroa from the east. There was an 80m-long breach in the eastern stopbank of the Ohinemuri River, which poured a torrent of floodwater through the town on the night of the 13th.
Total flood damage was estimated at $12,000,000 ($44,643,000 2010 dollars) in the Paeroa Borough and neighbouring districts of the Ohinemuri County.
544 homes were flooded and 229 houses suffered water damage. Entire household contents had to be dumped and motor vehicles were damaged.
Farmers sustained a substantial loss of highly productive pasture land. There were stock losses, kilometres of fencing was wrecked and thousands of bales of hay was damaged.
Ohinemuri River peaked at 9.5 metre which was almost one metre above the record 1936 flood.
Many houses had four, five or six feet (1.22-1.83 m) of silt-laden water through them and in some houses it was even deeper.
An estimated 3000 ha of pature was ruined by silt deposits.
Menzies Place area was the worst hit street in the town. Most houses had water through them from 0.3 m to 2 m.
The total cost of the household contents in the area was estimated at $2,000,000 ($7,441,000 2010 dollars).
A large number of motor vehicles were "drowned" by the floodwaters. The damage claim was estimated to be in excess of $1,000,000 ($3,720,000 2010 dollars).
About 40 commercial firms suffered damage through floodwaters entering their premises. One estimate put the cost in damage to buildings, goods and services close to $1,000,000 ($3,720,000 2010 dollars).
An estimate of the number of bales of hay lost in the storm was put at 42,000.
1264 sheep, 261 head of cattle, 13 deer and 2 horses were lost. The total value was estimated at $100,000 ($372,000 2010 dollars).
886 hectares had to be re-grassed due to silting. There was another 300 hectares of land lost through slips and erosion in the hills.
The total cost of the flood to the farming community was estimated to be as high as $500,000 ($1,860,000 2010 dollars).
Floodwaters entered cables, both telephone and electricity, and caused widespread disruption.
Highways and roads throughout the district were damaged and the repair bill for these alone was estimated at $1,500,000 ($5,580,000 2010 dollars).
The flood caused by the Ohinemuri River in Paeroa was a 50-year frequency flood.
High Wind / Gust
There were wind gusts up to 120 km/hr.
High Wind / Gust
at
Simpsons Beach (Wharekaho Beach)
One house had its roof blown of at Simpsons Beach.
Maritime / Coastal
at
Tairua
Tidal flooding closed the highway south of the township to Hikuai.
Flooding
at
Tapu
Several houses were evacuated on the morning of the 13th after the nearby creek burst its banks.
The centre of the town, including several houses and the post office, were under about one metre of water.
Heavy Rain
at
Te Aroha
Te Aroha recorded 368.6 mm (36.86 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of 60 years).
Te Aroha recorded 221.2 mm (22.12 cm) of rain in 24 hours from the 12th to the 13th.
Flooding
at
Te Puru
A number of Te Puru residents had to be evacuated.
Multi Hazard
Te Puru was hit severly by the storm. The motor camp was devastated and houses were undermined.
Multi Hazard
at
Thames
Thames was hit by torrential rain and gale force winds on the 12th and 13th of April.
Heavy Rain
Thames received over 400 mm (40.0 cm) of rain during the event.
A Civil Defence emergency was declared in the Thames-Coromandel area at 5:35am on the 13th to the 16th of April.
There was flooding of major rivers and mountain streams.
Schools were closed.
The flooded Karaka Stream caused much of the damage to property and services.
Tararu Stream washed out the road and large chunks of many of the sections along its banks and ruined new sewage and water pipes.
An early estimate of damage to Thames alone was $800,000 ($2,976,000 2010 dollars).
Transport was severely disrupted and several bridges and roads were cut off leaving Thames isolated. Water from the swollen Kauaeranga River and high tide covered State Highway 25 south of the Kauaeranga river bridge.
Silt had piled up inches thick in shops on Pollen Street after floodwater subsided.
Power went off around Thames about 8.45pm on the 12th after a slip near the Thames racecourse took away overhead lines. The power was restored until a circuit break blackout the western side of Thames. Power was restored to the whole Thames by midday on the 13th. There was a lack of drinking water because power to the pumps feeding the reservior had been cut and fresh water supplies became polluted with brown floodwaters.
The Karaka Creek burst its banks behind Thames Hospital and within the hour there were breaks in Hape, Waiotahi and Tararu waterways on the 13th. Karaka and Hape streams inundated the main commercial area of the town and deposited many tonnes of silt and debris on streets and in buildings.
The Thames-Paeroa rail link was disrupted with many washouts especially between Thames and Kirikiri. The line was reopened almost four weeks after the storm struck. The track suffered 50 washouts and th estimated cost was in excess of $200,000.
The town was partly evacuated due to flooding. Approximately 270 were evacuated from their homes.
Stopbanks and river control systems were extensively damaged or destroyed.
The Kauaeranga River rose to within 15 cm of topping the stopbanks at the southern end of town.
Many homes in the Grahamstown area were surrounded and others had floodwaters flowing through them.
In 24 to 36 hours the Kauaeranga River near Thames flooded three times. Stream flowing through Thames also flooded and broke their banks twice.
Silt 30 cm to 60 cm deep was left covering streets, gardens and in several places even in the houses.
It was the worst flood since the 1930's and was just as bad the 1917 flood disaster.
High Wind / Gust
Wind gusts of up to 80 knots (148 km/hr) were recorded.
Heavy Rain
at
Waihi
Waihi recorded 257.8 mm (25.78 cm) of rain in 24 hours from the 12th to the 13th.
Waihi recorded 445 mm (44.5 cm) of rain in 48 hours.
Waihi recorded 520.7 mm (52.07 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of over 150 years).
Flooding
There was a lot of water between Waihi and Whangamata.
Some streets in residential areas were under water up to 2 cm deep.
Patches of backyards and front gardens were flooded.
A small number of homes and sections in the lower areas had water entering some rooms. The was home flooding in Seddon Street and Union Street.
Waihi only received minor damage from flooding.
Athenree Gorge was closed for a period.
High Wind / Gust
One farmer had six cows electrocuted by power lines which were downed by the high winds.
Flooding
at
Waikino
Water completely demolished a string of buildings that made up one side of the towns main street at 6:30pm on the 12th after the river rose 4 metres in 30 minutes. The post office, two craft shops, a restaurant and two family homes were swept down the Ohinemuri River.
At peak of flood the water was 10 ft (3.05 m) high in the town.
Only the Waikino Tavern, the 100-year-old former hotal, withstood the deluge. Water swirled more than waist high through the ground floor. The damage to the tavern amounted to at least $20,000 to $30,000 ($74,400-$111,600).
Several cars parked on the street were damaged by floodwaters.
Power and telephone services to Waikino were torn out by the flood.
A "tidemark" on the side of the tavern showed where the river had swollen 2.4 m above the road.
High Wind / Gust
at
Whangamata
Roofing iron was blown off, windows were blown out, caravans were blown over, many trees were uprooted, telephone lines were brought down and masses of sand in swirling clouds landed on the grass verges.
60 to 70 knot (111-130 km/hr) gales were blowing out at sea from Whangamata.
Flooding
Surface water flooded many streets, but damage to shops and homes was minimal.
The town was cut off by road until late on the 13th.
Multi Hazard
at
Whitianga
The township was isolated.
Slips caused road damage in the area and the whole coastal strip between Whitianga and Tairua has been cut off when flooding washed away roads. State Highway 25 into Whitianga was closed and the 309 road to Coromandel was the only road open.
Bay of Plenty
Multi Hazard
at
Bay of Plenty
There was heavy rain and strong winds from the 11th.
Flooding
There was minor surface flooding in residential and rural areas.
High Wind / Gust
Power was cut for periods in places.
The most serious longterm effect of the storm was on the quality of some of the kiwifruit and tamarillo crops.
On the 13th, the highest wind gust obtained by averaging for Rotorua, Gisborne and Tauranga was 45 knots (83 km/hr) (which has a return period of five years).
Heavy Rain
at
Katikati
Tauranga County water treatment plant near Katikati recorded 159.5 mm (15.95 cm) of rain in 48 hours to 9am on the 13th.
High Wind / Gust
at
Mount Maunganui
Mount Manganui recorded gusts up to 60 knots (111 km/hr).
Heavy Rain
at
Omokoroa
Omokoroa recorded 102 mm (10.2 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 56 mm (5.60 cm) was recorded.
High Wind / Gust
Four boats were blown ashore at Omokoroa.
Heavy Rain
at
Tauranga
Tauranga sewage treatment plant at Chapel Street recorded 107.4 mm (10.74 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 31.1 mm (3.11 cm) was recorded.
Tauranga airport recorded 88.2 mm (8.82 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 24.8 mm (2.48 cm) was recorded.
Tauranga airport recorded 50 mm (5.0 cm) of rain from 9am to 3pm on the 12th.
Flooding
Paddocks were flooded but effects of the flooding in the city was limited.
There were leaking roofs.
High Wind / Gust
Less protected younger kiwifruit crops may have suffered during high winds.
The strongest wind gust recorded on the 12th at Tauranga airport was 35 knots (65 km/hr).
Trees caused most problems in Tauranga with power cuts.
Heavy Rain
at
Te Puke
Te Puke recorded 65 mm (6.5 cm) of rain in 24 hours to 8am on the 13th. In the previous 24 hours 27.1 mm (2.71 cm) was recorded.
Wellington
High Wind / Gust
at
Paraparaumu
Several houses lost sections of their roofs and some bus-stops were badly damaged in Paraparaumu.
Between 7:30pm to 8:30pm on the 12th the winds averaged 45 knots (83 km/hr) with a maximum gust of 67 knots (124 km/hr).
References
- Collen, B. and Hessel, J.W.D. (1981). The Thames-Coromandel Floods of April 1981. NZ Meteorological Service, Technical Information Circular No.183.
- Collen, B. and Hessel, J.W.D. (1982). Flood Producing Rain In Thames-Coromandel, New Zealand, April 1981. Weather and Climate (1982) 2: 30-36.
- Ericksen, H.J. (1986). Creating Flood Disasters? Water and Soil Miscellaneous Publication Number 77.
- History of Flood Events on the Thames Coast, Environment Waikato
- Insurance Councils, The Cost of Weather Loses, Claims history (Updated 2004)
- Major weather events in New Zealand, FLOODS AND HIGH RAINFALL, Floods to 31st July 2006
- MCDEM,2002
- NZ Met Service. (2008). Meteorology of Extreme Rainfalls in New Zealand (Mark Pascoe, Ed.).
- State of Emergency Declarations in the district since 1976, Environment Waikato
- Headline: Civil Emergency - Hundreds Shelter.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Disaster Diary.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Savage destruction and countless losses were suffered in yesterday's devastating floods.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Storm Hits Peninsula.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Thames previously had its worst storm damage in July 1875 and Febraury 1917…
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Worst In Fifty Years.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Fireman Say Flood Worst …
- Thames Star, 23 April (Thursday) 1981.
- Headline: Flood Special.
- Thames Valley Gazette, Flood Special, 11 April (Sunday) 1981:
- Headline: Rain and winds lash Bay.
- The Bay Of Plenty Times, 13 April 1981.
- Headline: Highway could be out for week.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Most of historic Waikino has vanished, river sweeps shops away.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Refuge in tavern.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Sunshine heralds end of Thames emergency.
- The Bay of Plenty Times, 14 April 1981.
- The Floods: The 1981 Thames Valley Flood Disaster, Thames Star and Hauraki Herald.
- Headline: Frantic Battle To save Town From Rising River.
- The New Zealand Herald, 13 April (Monday) 1981.
- Headline: Buildings Ripped Away In Torrent.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Clean-up After Wind Damage.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Terror Hits By Night, Breakaway River Sweeps Aside Paeroa Defences.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Flood Ebbs But Alert Stays On.
- The New Zealand Herald, 15 April (Wednesday) 1981.
- Headline: Residents Pull Together In Waikino Debris.
- The New Zealand Herald, 15 April (Wednesday) 1981.
- Headline: Homeless Turn for Help.
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Slip Damage Worst Blow.
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Threat of Rain Spurs Paeroa Flood Repairs
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Volunteers Flock To Spend Holiday Helping Paeroa Clean Up.
- The New Zealand Herald, 20 April (Monday) 1981.
- Headline: When the Real Test Came Paeroa's Luck Finally Ran Out.
- The New Zealand Herald, 20 April (Monday) 1981.
- Headline: Cows electrocuted.
- The Waikato Times, 13 April 1981.
- Headline: Drought ends for farmers.
- The Waikato Times, 13 April 1981.
- Headline: Rising floodwaters force hundreds out.
- The Waikato Times, 13 April 1981.
- Headline: Buildings washed into river.
- The Waikato Times, 14 April 1981.
- Headline: Thames scraping off the sludge.
- The Waikato Times, 15 April 1981.
- Headline: Disaster claims well up.
- The Waikato Times, 16 April 1981.
- Headline: Flooded towns 'no place' for Easter visits.
- The Waikato Times, 16 April 1981.
- Headline: Waihi Has Minor Damage As Valley Knocked By Biggest Flood On Record.
- Waihi Gazette, 14 April (Tuesday) 1981.
- Headline: Storm: Property Damaged, Power, Phones Out, And Trouble At Sea.
- Waihi Gazette, 21 April (Tuesday) 1981.
- Headline: Work Has Gorge Open.
- Waihi Gazette, 21 April (Tuesday) 1981.
- Workshop on Wind damage in New Zealand Exotic Forests, Ministry of Forestery, FRI Bullrtin 146, Accounting for New Zealand Plantation's Risk to Wind Damage - facing the facts, David New
- Workshop on Wind damage in New Zealand Exotic Forests, Ministry of Forestery, FRI Bullrtin 146, Wind risk in the Bay of Plenty, P.C. Brown and S. Jones
April 1981 Waikato Storm
(
1981-04-11
)
50-64 years
Torrential rain and high winds struck the Thames-Coromandel area and inland to Paeroa. Paeroa and Thames suffered considerable flooding and over 2000 people were evacuated during the event. Half the town of Waikino was completely destroyed when Ohinemuri River flooded. A Civil Defence emergency was declared in the Paeroa Borough and Ohinemuri County and the Thames-Coromandel area.
North Island
Multi Hazard
at
North Island
Duration: 6 days - From the 11th to the 16th of April 1981.
Insurance industry payouts for the Thames, Coromandel and Paeroa floods amounted to $7,000,000 in 1981 ($26,042,000 2010 dollars).
The strong easterly air flow was caused by a deep depression north-west of North Cape and an anti-cyclone centred east of Christchurch.
There was no loss of life.
Auckland
Flooding
at
Auckland
Water from an overflowing culvert closed the main trunk line between Mercer and Tuakau on the 13th.
High Wind / Gust
at
Auckland City
Wind gusts of up to 61 knots (113 km/hr) were recorded in Auckland.
West Auckland was without electricity on the 13th and 14th. 34 major electricity feeders were put out of action in the Auckland Electric Power Board area, and 20 more in Franklin.
Power lines and trees were blown down.
Telephone services in Auckland were slightly impaired when several lines were broken in the wind.
Firemen were called out 120 times for pumping where roofs were blown off.
Maritime / Coastal
A section of the seawall at Mission Bay was collapsed.
11 boats, mostly large expensive yachts, were found on the 13th stranded on the rocks around the Auckland waterfront.
Flooding
at
Takapuna
There were some stormwater problems in Takapuna City.
High Wind / Gust
at
Waitemata Harbour
At least 30 boats went missing from the Waitemata Harbour.
Waikato
Heavy Rain
at
Waikato
There was torrential rain in Waikato on the 12th and 13th which caused flooding in the region.
Flooding
Between 7000 and 10,000 hectares of farmland between Paeroa and Thames was flooded.
The worst areas of flooding seemed to be around Paeroa, Thames, Waikino, Hikutaia, Wharepoa, Puriri and Matatoki. The floodwaters left a lot of silt on pastures.
Up to 2250 people were evacuated in the Thames, Paeroa and Waihi area.
Stock losses were minimal and were generally only young stock.
Rivers in high flood included the Te Puru, Tararu, Kaueranga, Kirikiri, Matatoki, Hikutaia, Komata, Waitoki, Mangaiti, Waiorongomai, Tairua, Ohinemuri.
It was the worst Coromandel flood on record to date and exceeded that of 1954 in severity and arial distribution of heavy rainfalls.
The main road from Auckland to the Bay of Plenty was flooded in the Pokeno valley and at Mangatawhiri. At that point farmland was completely submerged, with only the tops of fences and trees visible.
High Wind / Gust
Wind velocity was constant at 50 knots (92.6 km/hr).
One pleasure boat was sunk and several others broke loose from there moorings and were damaged during the gale on the eastern seaboard of the Coromandel Peninsula.
Gale force winds affected coastal areas.
Landslide
The Kopu-Hikuai Road was closed by slips in many places.
Hill country farmers suffered a lot from slips. The main effect of the slips has been to sweep away fencing.
Multi Hazard
The highway from Paeroa to Waihi was closed by slips and washouts.
Highway 25 south of Coroglen and south of Whangamata was closed on the night of the 12th as was Highway 2 between Paeroa and Waihi at Queen's Head.
Heavy Rain
at
Coromandel Range
The Coromandel Ranges received an estimated 850 mm (85.0 cm) of rain in 72 hours.
The Coromandel Ranges received an estimated 500+ mm (50.0 cm) of rain in 24 hours.
High Wind / Gust
at
Hahei
Strong winds blew off the roofs of six houses at Hahei and partially destroyed another home there.
Flooding
at
Hikutaia
Some residents had to be evacuated when floodwaters threatened their homes.
Flooding
at
Karangahake Gorge
In many parts of the Karangahake Gorge, road sealing had been ripped up and debris was scattered over the highway in many parts. The gorge road was finally opened back up on the morning of the 21st of April.
Heavy Rain
at
Kauaeranga River
Kauaeranga catchment received 870 mm (87.0 cm) of rain in 72 hours (which has a return period of over 150 years).
Kauaeranga catchment received 900 mm (90.0 cm) of rain during the storm event.
Heavy Rain
at
Ohinemuri River
Ohinemuri catchment received 700 mm (70.0 cm) of rain during the storm event.
Ohinemuri catchment received over 550 mm (55.0 cm) of rain from the 11th to the 12th.
Flooding
The river was running 10 metres or more than normal in places.
Flooding
at
Opoutere
Farmers at Opoutere were without power for a long period
Flooding of farmland was extensive in the area.
High Wind / Gust
at
Otama
One house was totally destroyed at Otama.
Heavy Rain
at
Paeroa
Paeroa recorded 197.9 mm (19.79 cm) of rain in 24 hours from the 12th to the 13th.
Paeroa recorded 375.8 mm (37.58 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of over 100 years).
Paeroa recorded 346.5 mm (34.65 cm) of rain in 48 hours (which has a return period of 90 years).
Flooding
A Civil Defence emergency was declared in the Paeroa Borough and Ohinemuri County from 5:39pm on the 12th to the 21st of April.
The Paeroa area received approximately 400 mm (40.0 cm) during the storm.
All businesses were closed.
Schools were closed.
Dozens of men piled more than 15,000 sandbags against a stopbank of the Ohinemuri River on the night of the 12th. Sandbags were also used to build dams around shops.
The main street and some side streets were under several centimetres of water.
The Ohinemuri River was running about 4 metres above its usual level and was lapping at the edge of the Criterion Bridge leading into town.
There was a major evacuation of town. Low-lying residences and businesses were evacuated. More than 1000 people were evacuated in the Paeroa district.
The district's highways and roads were battered into closure. Roads to Waihi, Thames and State Highway 2 to Auckland were cut.
In 24 to 36 hours the Ohinemuri River, which flows through Paeroa, flooded twice.
Paeroa's main pipeline was broken in a number of places and people were told to use water sparingly. Fresh water supplies became polluted with brown floodwaters.
Sewage from the town's outfall was floating in the floodwaters, creating a health hazard. All furnishings and household effects were contaminated.
A large part of the town was underwater.
Air Force Helicopters were used to check the safety of families in outlying valleys and drop food to them.
The flooding was caused by the overtopping and breaching of ageing stopbanks along the Ohinemuri River west of town, and by the overflow from recently canalised tributary streams that traverse Paeroa from the east. There was an 80m-long breach in the eastern stopbank of the Ohinemuri River, which poured a torrent of floodwater through the town on the night of the 13th.
Total flood damage was estimated at $12,000,000 ($44,643,000 2010 dollars) in the Paeroa Borough and neighbouring districts of the Ohinemuri County.
544 homes were flooded and 229 houses suffered water damage. Entire household contents had to be dumped and motor vehicles were damaged.
Farmers sustained a substantial loss of highly productive pasture land. There were stock losses, kilometres of fencing was wrecked and thousands of bales of hay was damaged.
Ohinemuri River peaked at 9.5 metre which was almost one metre above the record 1936 flood.
Many houses had four, five or six feet (1.22-1.83 m) of silt-laden water through them and in some houses it was even deeper.
An estimated 3000 ha of pature was ruined by silt deposits.
Menzies Place area was the worst hit street in the town. Most houses had water through them from 0.3 m to 2 m.
The total cost of the household contents in the area was estimated at $2,000,000 ($7,441,000 2010 dollars).
A large number of motor vehicles were "drowned" by the floodwaters. The damage claim was estimated to be in excess of $1,000,000 ($3,720,000 2010 dollars).
About 40 commercial firms suffered damage through floodwaters entering their premises. One estimate put the cost in damage to buildings, goods and services close to $1,000,000 ($3,720,000 2010 dollars).
An estimate of the number of bales of hay lost in the storm was put at 42,000.
1264 sheep, 261 head of cattle, 13 deer and 2 horses were lost. The total value was estimated at $100,000 ($372,000 2010 dollars).
886 hectares had to be re-grassed due to silting. There was another 300 hectares of land lost through slips and erosion in the hills.
The total cost of the flood to the farming community was estimated to be as high as $500,000 ($1,860,000 2010 dollars).
Floodwaters entered cables, both telephone and electricity, and caused widespread disruption.
Highways and roads throughout the district were damaged and the repair bill for these alone was estimated at $1,500,000 ($5,580,000 2010 dollars).
The flood caused by the Ohinemuri River in Paeroa was a 50-year frequency flood.
High Wind / Gust
There were wind gusts up to 120 km/hr.
High Wind / Gust
at
Simpsons Beach (Wharekaho Beach)
One house had its roof blown of at Simpsons Beach.
Maritime / Coastal
at
Tairua
Tidal flooding closed the highway south of the township to Hikuai.
Flooding
at
Tapu
Several houses were evacuated on the morning of the 13th after the nearby creek burst its banks.
The centre of the town, including several houses and the post office, were under about one metre of water.
Heavy Rain
at
Te Aroha
Te Aroha recorded 368.6 mm (36.86 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of 60 years).
Te Aroha recorded 221.2 mm (22.12 cm) of rain in 24 hours from the 12th to the 13th.
Flooding
at
Te Puru
A number of Te Puru residents had to be evacuated.
Multi Hazard
Te Puru was hit severly by the storm. The motor camp was devastated and houses were undermined.
Multi Hazard
at
Thames
Thames was hit by torrential rain and gale force winds on the 12th and 13th of April.
Heavy Rain
Thames received over 400 mm (40.0 cm) of rain during the event.
A Civil Defence emergency was declared in the Thames-Coromandel area at 5:35am on the 13th to the 16th of April.
There was flooding of major rivers and mountain streams.
Schools were closed.
The flooded Karaka Stream caused much of the damage to property and services.
Tararu Stream washed out the road and large chunks of many of the sections along its banks and ruined new sewage and water pipes.
An early estimate of damage to Thames alone was $800,000 ($2,976,000 2010 dollars).
Transport was severely disrupted and several bridges and roads were cut off leaving Thames isolated. Water from the swollen Kauaeranga River and high tide covered State Highway 25 south of the Kauaeranga river bridge.
Silt had piled up inches thick in shops on Pollen Street after floodwater subsided.
Power went off around Thames about 8.45pm on the 12th after a slip near the Thames racecourse took away overhead lines. The power was restored until a circuit break blackout the western side of Thames. Power was restored to the whole Thames by midday on the 13th. There was a lack of drinking water because power to the pumps feeding the reservior had been cut and fresh water supplies became polluted with brown floodwaters.
The Karaka Creek burst its banks behind Thames Hospital and within the hour there were breaks in Hape, Waiotahi and Tararu waterways on the 13th. Karaka and Hape streams inundated the main commercial area of the town and deposited many tonnes of silt and debris on streets and in buildings.
The Thames-Paeroa rail link was disrupted with many washouts especially between Thames and Kirikiri. The line was reopened almost four weeks after the storm struck. The track suffered 50 washouts and th estimated cost was in excess of $200,000.
The town was partly evacuated due to flooding. Approximately 270 were evacuated from their homes.
Stopbanks and river control systems were extensively damaged or destroyed.
The Kauaeranga River rose to within 15 cm of topping the stopbanks at the southern end of town.
Many homes in the Grahamstown area were surrounded and others had floodwaters flowing through them.
In 24 to 36 hours the Kauaeranga River near Thames flooded three times. Stream flowing through Thames also flooded and broke their banks twice.
Silt 30 cm to 60 cm deep was left covering streets, gardens and in several places even in the houses.
It was the worst flood since the 1930's and was just as bad the 1917 flood disaster.
High Wind / Gust
Wind gusts of up to 80 knots (148 km/hr) were recorded.
Heavy Rain
at
Waihi
Waihi recorded 257.8 mm (25.78 cm) of rain in 24 hours from the 12th to the 13th.
Waihi recorded 445 mm (44.5 cm) of rain in 48 hours.
Waihi recorded 520.7 mm (52.07 cm) of rain in 72 hours from the 11th to the 14th (which has a return period of over 150 years).
Flooding
There was a lot of water between Waihi and Whangamata.
Some streets in residential areas were under water up to 2 cm deep.
Patches of backyards and front gardens were flooded.
A small number of homes and sections in the lower areas had water entering some rooms. The was home flooding in Seddon Street and Union Street.
Waihi only received minor damage from flooding.
Athenree Gorge was closed for a period.
High Wind / Gust
One farmer had six cows electrocuted by power lines which were downed by the high winds.
Flooding
at
Waikino
Water completely demolished a string of buildings that made up one side of the towns main street at 6:30pm on the 12th after the river rose 4 metres in 30 minutes. The post office, two craft shops, a restaurant and two family homes were swept down the Ohinemuri River.
At peak of flood the water was 10 ft (3.05 m) high in the town.
Only the Waikino Tavern, the 100-year-old former hotal, withstood the deluge. Water swirled more than waist high through the ground floor. The damage to the tavern amounted to at least $20,000 to $30,000 ($74,400-$111,600).
Several cars parked on the street were damaged by floodwaters.
Power and telephone services to Waikino were torn out by the flood.
A "tidemark" on the side of the tavern showed where the river had swollen 2.4 m above the road.
High Wind / Gust
at
Whangamata
Roofing iron was blown off, windows were blown out, caravans were blown over, many trees were uprooted, telephone lines were brought down and masses of sand in swirling clouds landed on the grass verges.
60 to 70 knot (111-130 km/hr) gales were blowing out at sea from Whangamata.
Flooding
Surface water flooded many streets, but damage to shops and homes was minimal.
The town was cut off by road until late on the 13th.
Multi Hazard
at
Whitianga
The township was isolated.
Slips caused road damage in the area and the whole coastal strip between Whitianga and Tairua has been cut off when flooding washed away roads. State Highway 25 into Whitianga was closed and the 309 road to Coromandel was the only road open.
Bay of Plenty
Multi Hazard
at
Bay of Plenty
There was heavy rain and strong winds from the 11th.
Flooding
There was minor surface flooding in residential and rural areas.
High Wind / Gust
Power was cut for periods in places.
The most serious longterm effect of the storm was on the quality of some of the kiwifruit and tamarillo crops.
On the 13th, the highest wind gust obtained by averaging for Rotorua, Gisborne and Tauranga was 45 knots (83 km/hr) (which has a return period of five years).
Heavy Rain
at
Katikati
Tauranga County water treatment plant near Katikati recorded 159.5 mm (15.95 cm) of rain in 48 hours to 9am on the 13th.
High Wind / Gust
at
Mount Maunganui
Mount Manganui recorded gusts up to 60 knots (111 km/hr).
Heavy Rain
at
Omokoroa
Omokoroa recorded 102 mm (10.2 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 56 mm (5.60 cm) was recorded.
High Wind / Gust
Four boats were blown ashore at Omokoroa.
Heavy Rain
at
Tauranga
Tauranga sewage treatment plant at Chapel Street recorded 107.4 mm (10.74 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 31.1 mm (3.11 cm) was recorded.
Tauranga airport recorded 88.2 mm (8.82 cm) of rain in 24 hours to 9am on the 13th. In the previous 24 hours 24.8 mm (2.48 cm) was recorded.
Tauranga airport recorded 50 mm (5.0 cm) of rain from 9am to 3pm on the 12th.
Flooding
Paddocks were flooded but effects of the flooding in the city was limited.
There were leaking roofs.
High Wind / Gust
Less protected younger kiwifruit crops may have suffered during high winds.
The strongest wind gust recorded on the 12th at Tauranga airport was 35 knots (65 km/hr).
Trees caused most problems in Tauranga with power cuts.
Heavy Rain
at
Te Puke
Te Puke recorded 65 mm (6.5 cm) of rain in 24 hours to 8am on the 13th. In the previous 24 hours 27.1 mm (2.71 cm) was recorded.
Wellington
High Wind / Gust
at
Paraparaumu
Several houses lost sections of their roofs and some bus-stops were badly damaged in Paraparaumu.
Between 7:30pm to 8:30pm on the 12th the winds averaged 45 knots (83 km/hr) with a maximum gust of 67 knots (124 km/hr).
References
- Collen, B. and Hessel, J.W.D. (1981). The Thames-Coromandel Floods of April 1981. NZ Meteorological Service, Technical Information Circular No.183.
- Collen, B. and Hessel, J.W.D. (1982). Flood Producing Rain In Thames-Coromandel, New Zealand, April 1981. Weather and Climate (1982) 2: 30-36.
- Ericksen, H.J. (1986). Creating Flood Disasters? Water and Soil Miscellaneous Publication Number 77.
- History of Flood Events on the Thames Coast, Environment Waikato
- Insurance Councils, The Cost of Weather Loses, Claims history (Updated 2004)
- Major weather events in New Zealand, FLOODS AND HIGH RAINFALL, Floods to 31st July 2006
- MCDEM,2002
- NZ Met Service. (2008). Meteorology of Extreme Rainfalls in New Zealand (Mark Pascoe, Ed.).
- State of Emergency Declarations in the district since 1976, Environment Waikato
- Headline: Civil Emergency - Hundreds Shelter.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Disaster Diary.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Savage destruction and countless losses were suffered in yesterday's devastating floods.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Storm Hits Peninsula.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Thames previously had its worst storm damage in July 1875 and Febraury 1917…
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Worst In Fifty Years.
- Thames Star, 14 April (Tuesday) 1981.
- Headline: Fireman Say Flood Worst …
- Thames Star, 23 April (Thursday) 1981.
- Headline: Flood Special.
- Thames Valley Gazette, Flood Special, 11 April (Sunday) 1981:
- Headline: Rain and winds lash Bay.
- The Bay Of Plenty Times, 13 April 1981.
- Headline: Highway could be out for week.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Most of historic Waikino has vanished, river sweeps shops away.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Refuge in tavern.
- The Bay of Plenty Times, 14 April 1981.
- Headline: Sunshine heralds end of Thames emergency.
- The Bay of Plenty Times, 14 April 1981.
- The Floods: The 1981 Thames Valley Flood Disaster, Thames Star and Hauraki Herald.
- Headline: Frantic Battle To save Town From Rising River.
- The New Zealand Herald, 13 April (Monday) 1981.
- Headline: Buildings Ripped Away In Torrent.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Clean-up After Wind Damage.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Terror Hits By Night, Breakaway River Sweeps Aside Paeroa Defences.
- The New Zealand Herald, 14 April (Tuesday) 1981.
- Headline: Flood Ebbs But Alert Stays On.
- The New Zealand Herald, 15 April (Wednesday) 1981.
- Headline: Residents Pull Together In Waikino Debris.
- The New Zealand Herald, 15 April (Wednesday) 1981.
- Headline: Homeless Turn for Help.
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Slip Damage Worst Blow.
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Threat of Rain Spurs Paeroa Flood Repairs
- The New Zealand Herald, 16 April (Thursday) 1981.
- Headline: Volunteers Flock To Spend Holiday Helping Paeroa Clean Up.
- The New Zealand Herald, 20 April (Monday) 1981.
- Headline: When the Real Test Came Paeroa's Luck Finally Ran Out.
- The New Zealand Herald, 20 April (Monday) 1981.
- Headline: Cows electrocuted.
- The Waikato Times, 13 April 1981.
- Headline: Drought ends for farmers.
- The Waikato Times, 13 April 1981.
- Headline: Rising floodwaters force hundreds out.
- The Waikato Times, 13 April 1981.
- Headline: Buildings washed into river.
- The Waikato Times, 14 April 1981.
- Headline: Thames scraping off the sludge.
- The Waikato Times, 15 April 1981.
- Headline: Disaster claims well up.
- The Waikato Times, 16 April 1981.
- Headline: Flooded towns 'no place' for Easter visits.
- The Waikato Times, 16 April 1981.
- Headline: Waihi Has Minor Damage As Valley Knocked By Biggest Flood On Record.
- Waihi Gazette, 14 April (Tuesday) 1981.
- Headline: Storm: Property Damaged, Power, Phones Out, And Trouble At Sea.
- Waihi Gazette, 21 April (Tuesday) 1981.
- Headline: Work Has Gorge Open.
- Waihi Gazette, 21 April (Tuesday) 1981.
- Workshop on Wind damage in New Zealand Exotic Forests, Ministry of Forestery, FRI Bullrtin 146, Accounting for New Zealand Plantation's Risk to Wind Damage - facing the facts, David New
- Workshop on Wind damage in New Zealand Exotic Forests, Ministry of Forestery, FRI Bullrtin 146, Wind risk in the Bay of Plenty, P.C. Brown and S. Jones