Beban, J.G.; Cousins, W.J.; Mason, K.M.; Parnell, A. 2014 Potential for ground water bores to meet Lower Hutt's emergency water needs after large earthquakes. Lower Hutt, N.Z.: GNS Science. GNS Science report 2014/61 41 p.
Abstract: Large earthquakes in central New Zealand are expected to cause extensive damage to buildings and infrastructure, and to result in many deaths and injuries. Cities most affected include Wellington, Lower Hutt, Upper Hutt and Porirua. It is expected that all major transport routes (air, sea, rail, and road) out of the main urban area, and many within the area will be affected, and that there will be extended loss of bulk and reticulated water. Prior research has considered the impacts on Wellington of a prolonged loss of bulk water. Wellington was studied because is uniquely vulnerable due to: • The large distances to its bulk water sources; and • The lack of alternative sources within the city. The water situation in Lower Hutt has now been investigated. Lower Hutt is much less vulnerable than Wellington because one of the bulk water sources, the Waiwhetu artesian field, lies within its boundaries. There are many water bores in the valley floor part of the city, a major river, (the Hutt River), flows through the City, as do several small streams, and there are several reservoirs in the hills either side of the valley floor. The river, streams and reservoirs are not ideal sources of post-earthquake emergency water, the river and streams because of contamination risks, and the reservoirs because of the large distances between them and most of the valley-floor residents. For this reason we have evaluated the potential for the existing artesian bores, supplemented by additional emergency-only bores, to provide the necessary emergency water for the valley-floor people. Our first finding is that most of the residents of the valley floor live more than 1 km from their nearest existing large source of emergency water, be it a reservoir or a council-owned artesian bore. The distance of 1 km is important because larger distances make it very difficult for people to carry water from source to home. Our second finding is that an additional 16 new bores, strategically located in large open areas of the city, would ensure that the vast majority of the residents will be within 1 km of a suitable emergency-water source. (auth)
