The Lacepede District Council is considering a proposal for the construction of a marina and associated infrastucture in Maria Creek, Kingston (South-East). The proposal includes two options, A and B, with Option A sited closest to existing town amenities. Option B involves excavating the marina further to the north near the outlet of Maria Creek. The proposal has been forwarded to MESA for an assessment of the hydrogeology of the site and possible effects of the marina on groundwater quality in nearby private and council water supply bores. An assessment of groundwater monitoring data indicates that there is unlikely to be any adverse impact on the local groundwater resources from Option B. The worst scenario for Option A could result in a 50 m lateral shift away from Maria Creek of the existing salinity profiles in the Bridgewater Formation aquifer. A further program of monitoring is recommended which includes intensive groundwater monitoring during periods of peak high tides to assess the tidal efficiencies of both aquifers, continued monitoring to assess the impacts of surface water flows in Maria Creek, and a small trial excavation with associated monitoring. It may also be possible to mitigate any such impacts of Option A through the use of stormwater recharge trenches located just inland of the proposed marina.