Mapping shallow groundwater salinity in a coastal urban setting to assess exposure of municipal assets

Christchurch, New Zealand. Low-lying coastal cities worldwide are vulnerable to shallow groundwater salinization caused by saltwater intrusion and anthropogenic activities. Shallow can have cascading negative impacts on municipal assets, but this is rarely considered compared of water supply. Here, salinity was sampled at high spatial resolution (1.3 piezometer/km2), then mapped spatially interpolated. This possible due a uniquely extensive set piezometers installed in response the 2010–11 Canterbury Earthquake Sequence assess liquefaction risk. The assets located within brackish areas were highlighted. Brackish centred spit sand dunes inside meander tidal river with poorly drained soils. these include: (i) wastewater stormwater pipes constructed from steel-reinforced concrete, which, if damaged, premature failure when exposed chloride underwater, (ii) 41 parks reserves totalling 236 ha, which salt-intolerant groundwater-dependent species research highlights importance determining saline low-lying urban settings co-located allow prioritisation sites for future monitoring management.