Environment Canterbury

摘要

Two exceptionally large rainfall events dominated the hydrology of NorthCanterbury over the winter. The first event was at the end of July, with a maximumrainfall of 212 mm in 24 hours just north of Kaikoura and a 48-hour rainfall atHurunui State Highway 1 with an average recurrence interval of 1:20 years. Thisrainfall resulted in flooding all across North Canterbury and Kaikoura. This floodevent occurred at the same time as particularly high tides, which caused theevacuation of residents in some coastal settlements near rivers. The Hurunui atState Highway 1, Cust, Hawkins, and Kowai North Branch all recorded themaximum flows since their records began, with estimated average return intervalsof between 20 and 50 years.