Date | 17-18 July 2021 |
---|---|
Location | central New Zealand |
Property damage | $140.47 million [1] |
The 2021 central New Zealand floods were the result of a torrential rainstorm that affected central New Zealand between 17 and 18 July 2021. This storm led to flooding in the West Coast's Buller District, the Tasman District, and the Marlborough Region in the South Island, prompting the evacuations of residents and the declaration of a state of emergency. [2] [3] [4] Flooding also impacted the Wellington region. [5]
The floods came nearly two months after flooding in Canterbury [6] and just over a month before flooding in Auckland. [7]
According to the National Institute of Water and Atmospheric Research (NIWA), large areas of New Zealand experienced above normal rainfall and above normal temperatures in July 2021, making that month the sixth-equal warmest July on record. The mean temperate for July 2021 was 8.9 Celsius, which is 1.1 Celsius warmer than the 1981–2010 average. According to NIWA meteorologist Chris Brandoloni, the previous month of June 2021 was the warmest recorded, and that the first seven months of the year were also the warmest since records began in 1909. Brandoloni attributed the extreme rain and heat events to climate change. [8]
The extreme rain event of 15–18 July brought over 690 mm (27 in) of rain to parts of the West Coast Region in under 72 hours. The Buller River also experienced the country's largest flood flows since 1926 as a result of the deluge. [8] Parts of the West Coast experienced 300 mm (12 in) of rain over the weekend of 17–18 July, roughly a month's average rainfall. The heavy rain causes rivers to break their banks and landslips, leading to the evacuation of 2,000 residents. [9]
In addition to the West Coast, the South Island's Marlborough Region, Nelson, Tasman District, Canterbury high country, and North Otago experienced well above average rainfall (more than 149% of the normal rainfall). [8] Parts of the Marlborough Region recorded more than 300 mm (12 in) of rain in the 48-hour period between 16 and 18 July. Onamalutu, just west of Renwick, recorded 212 mm (8.3 in) of rain on 17 July while Tunakino Valley recorded 103.5 mm (4.07 in) on 16 July. River levels within the region jumped with the Wairau River at Barnett's Bank near Tuamarina reaching almost 9 m (30 ft) and a peak flow of 6,040 cumecs on 17 July. [10] Parts of the North Island (including the Northland Region, the inland Bay of Plenty, the Wellington Region, and the Kāpiti Coast) also experienced above average levels of rainfall. [8]
Climate expert Dr. Luke Harrington also attributed the heavy rain in the West Coast to climate change and an atmospheric river carrying moisture from the tropics. The high rainfall was also exacerbated by warmer than average sea surface temperatures, another effect of climate change. Harrington predicted that such atmospheric rivers would become more intense and frequent throughout the world as a result of climate change. The Buller and Marlborough Regions were more vulnerable to stormy weather since their geographical location meant they were trapped between incoming moisture-laden atmospheric rivers and the Southern Alps, causing the air to compress and the rain to fall. [11]
As a result of the flooding, 430 residents were evacuated from Spring Creek near Blenheim, Tuamarina township in the Marlborough Region on the evening of 17 July. In addition, about half of Westport's 4,600 residents were evacuated that same day. By 18 July, 1,000 displaced residents were still unable to return. [12]
On 19 July, a state of emergency was declared in the Marlborough Region. Nine hundred people were evacuated across 500 properties in the region, including properties in Renwick, Spring Creek, and Tuamarina. Dozens of roads were closed in the region, and an order to boil drinking water was instated in the Wairau Valley. Deputy Mayor Nadine Taylor described the 2021 flood as the region's largest recorded flood, exceeding the 1983 flood. [10]
On 20 July, West Coast Emergency Management reported that 89 houses in the region had suffered severe or total damage (red category) and 400 had suffered moderate damage as a result of the torrential rain and flooding. [13] By 21 July, Buller District Mayor Jamie Cleine reported that 22 homes in the district were still "red stickered," meaning that residents could not return home to live before repair work was done. A hundred people still remained the area's three evacuation centres (one of which was a school). [14]
The flooding caused millions of dollars in damages and damaged 563 homes in Westport; with 70 being red stickered and 393 being yellow stickered. [15] [16] By mid-October 2021, 450 Westport homes remained uninhabitable or damaged with 140 residents in temporary accommodation. [17] In July 2022, Stuff reported that over 400 homes in Westport had not been fully repaired since the floods that struck the city in July 2021. Of the 563 flood damaged homes, just over 100 had fully completed their repairs. [18]
The event resulted in $140.47 million dollars of insurance claimed damage in New Zealand. [1] Of this, $97.2 million was in the West Coast region, $17.88 million was in the Wellington region, $17.35 million was in the upper South Island, and $8.04 million was in the rest of the North Island. [5]
In response to the flooding in the West Coast Region, the New Zealand Defence Force deployed more than 30 personnel and soldiers, four Unimogs, and a Royal New Zealand Air Force helicopter. Defence Force personnel conducted emergency food drops to rural areas, cooked for up to 300 emergency responders, and assisted with the evacuation of over 800 properties. [14]
On 18 July, Acting Minister for Emergency Management Kris Faafoi announced that the Government would provide $NZ 600,000 in emergency aid to affected regions. Minister of Agriculture Damien O'Connor also announced financial support for farmers. The West Coast District Health Board stated that it would take months to clean affected homes. [9]
In July 2022, the Buller District Council and the West Coast Regional Council submitted a NZ$54 million business case for the West Coast region which includes investing in flood walls, subsidising people to move from flood-prone areas, and investing in Westport's stormwater system. [18]
Westport is a town in the West Coast region of the South Island of New Zealand. Established in 1861, it is the oldest European settlement on the West Coast. Originally named Buller, it is on the right bank and at the mouth of the Buller River, close by the prominent headland of Cape Foulwind. It is connected via State Highway 6 with Greymouth, 100 kilometres (62 mi) to the south, and with Nelson 222 kilometres (138 mi) in the northeast, via the Buller Gorge. The population of the Westport urban area was 4,250 as of June 2023. The Buller District had a population of 9,670.
Hurricane Gordon caused minor damage in the Eastern United States. The seventh named storm and fourth hurricane of the 2000 Atlantic hurricane season, Gordon developed in the extreme western Caribbean Sea from a tropical wave on September 14. Shortly thereafter, the depression moved inland over the Yucatán Peninsula and later emerged into the Gulf of Mexico on September 15. The depression began to quickly organize, and by early on September 16, it was upgraded to Tropical Storm Gordon. After becoming a tropical storm, Gordon continued to intensify and was reclassified as a hurricane about 24 hours later; eventually, the storm peaked as an 80 mph (130 km/h) Category 1 hurricane. However, southwesterly upper-level winds caused Gordon to weaken as it approached land, and it was downgraded to a tropical storm by late on September 17. At 0300 UTC on September 18, Gordon made landfall near Cedar Key, Florida as a strong tropical storm. After moving inland, Gordon rapidly weakened and had deteriorated to tropical depression status by nine hours later. Later that day, Gordon merged with a frontal boundary while centered over Georgia.
Floods in the United States (2000–present) is a list of flood events which were of significant impact to the country during the 21st century, since 2000. Floods are generally caused by excessive rainfall, excessive snowmelt, storm surge from hurricanes, and dam failure.
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The 1929 Murchison earthquake occurred at 10:17 am on 17 June. It struck the Murchison region of the South Island, with an estimated magnitude of 7.3, and was felt throughout New Zealand. There were 17 deaths, mostly as a result of landslides triggered by the earthquake. The rumbling sound of the earthquake was loud enough to be heard at New Plymouth, more than 250 km (155 mi) away.
The 2010 Gascoyne River flood was regarded as the most severe flood to take place along the Gascoyne River in Western Australia on record. Triggered by record-breaking rainfall, amounting to over 6,000 percent of the monthly mean, 313.6 mm (12.35 in) and 5 mm (0.20 in) respectively, in just four days, the floods caused widespread damage in the region. By 17 December, the river began to rise in response to the heavy rains, eventually exceeding its banks within two days. Water levels reached record values at three stations along the river, cresting at 15.53 m (51.0 ft) near Fishy Pool. Evacuation orders were issued for several towns affected by rising waters. The most substantial impact was felt in Carnarvon where entire homes were washed away. Following the disaster, emergency supplies and funds were distributed to affected residents to aid them in restoring their livelihoods. Though no people died in the event, an estimated two thousand head of cattle perished and damage was estimated at A$100 million.
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Hurricane Harvey was a devastating Category 4 hurricane that made landfall on Texas and Louisiana in August 2017, causing catastrophic flooding and more than 100 deaths. It is tied with 2005's Hurricane Katrina as the costliest tropical cyclone on record, inflicting $125 billion in damage, primarily from catastrophic rainfall-triggered flooding in the Houston metropolitan area and Southeast Texas; this made the storm the costliest natural disaster recorded in Texas at the time. It was the first major hurricane to make landfall in the United States since Wilma in 2005, ending a record 12-year span in which no hurricanes made landfall at the intensity of a major hurricane throughout the country. In a four-day period, many areas received more than 40 inches (1,000 mm) of rain as the system slowly meandered over eastern Texas and adjacent waters, causing unprecedented flooding. With peak accumulations of 60.58 in (1,539 mm), in Nederland, Texas, Harvey was the wettest tropical cyclone on record in the United States. The resulting floods inundated hundreds of thousands of homes, which displaced more than 30,000 people and prompted more than 17,000 rescues.
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