17 Jul 2021 | 07:53 AM UTC
New Zealand: State of emergency in Buller and Marlborough districts due to heavy rain and flooding July 17 /update 2
Weather warnings in place in central, western, and northeastern New Zealand through at least July 17. Flash flooding, disruptions ongoing.
Event
A local state of emergency is in effect in Buller and Marlborough districts as of evening July 17 due to heavy rain. Officials have issued evacuation orders for residents in parts of Marlborough District, including Lower Wairau, Spring Creek township, and Lower Terrace in Renwick. Local authorities expanded evacuation orders in Westport to include homes along Brougham Street and Eastons Road near the Orowaiti lagoon. Precautionary evacuations are also ongoing in Newlands, Wellington, following a slip. Reports indicate that heavy rains and strong winds caused some infrastructural damage to homes in the Wellington region, including the Hutt and Kapiti areas; there have been no reports of injuries.
Heavy rainfall continues to be forecast in portions of central, western, and northeastern New Zealand through at least July 17. The affected areas include the eastern Bay of Plenty, western Canterbury, western Gisbourne, western Manawatu-Wanganui, Marlborough, Taranaki, far southern Waikato, far southern and western Wellington, and West Coast regions. As of July 17, the New Zealand National Meteorological Service (MetService) has issued the following warnings:
Red Heavy Rain Warning (the highest level on a three-tier scale): Buller; a further 70 to 120mm (3-5 inches) of rainfall could occur in these areas.
Orange Heavy Rain Warning(the middle level on a three-tier scale): Bay Of Plenty east of Whakatane; the ranges of Gisborne; North Taranaki; the central high country between Taumarunui and Raetihi, including Tongariro National Park; Nelson west of Motueka; the Tararua Range; the inland ranges of Marlborough; the Richmond and Bryant ranges; Marlborough Sounds; the headwaters of the Canterbury lakes and rivers from the Rakaia river northwards; Westland north of Fox Glacier; 50-100 mm (2-4 inches) of rainfall could occur in these areas.
Yellow Heavy Rain Watch: Wellington; Nelson from Motueka eastwards; West of the Richmond and Bryant ranges.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
As of July 17, State Highway 1 is blocked at Johnsonville to Tawa and at Paremata. Additionally, State Highway 2 is closed from Ngauranga to Dowse due to flooding. The Wellington City Council has also advised motorists to Hutt Road between Kaiwharawhara and the Ngauranga Gorge due to extensive surface flooding.
Hazardous Conditions
Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed or a lack of stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall. Power outages could occur throughout the affected area.
Transport
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. The disruptive weather may cause some delays and cancellations at regional airports. Authorities may temporarily suspend port operations along the Tasman Sea, Bay of Plenty, and Cook Strait if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding could block regional rail lines; freight cancellations are possible in areas that see heavy rainfall and potential track blockages.
Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved - it could take days before any floodwaters recede and/or officials clear debris. If there is severe damage to infrastructure, repair or reconstruction efforts may result in residual disruptions.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.