water stream over rocks


Assessing Ground Water Sustainability of the Island of Tutuila, American Samoa

Assessing Ground Water Sustainability of the Island of Tutuila, American Samoa

National Institute for Water Resources, Water Resources Research Institute Program

3/1/2013 - 2/28/2014

Anthropogenic and natural sources of contaminants on the island of Tutuila, American Samoa, represent a serious threat to groundwater, surface-water, coastal waters, and coral reefs. Major sources include streamside development, flow modification, loss of riparian vegetation, land-use changes, and human and pig waste disposal systems. Threats to groundwater are especially of major concern considering that subsurface sources provide about 99% of drinking water. Protection of water resources is critical, especially with growing population, increased waste production, and declining arable land. The problems will even worsen due to climate change and sea level rise. Issues related to sustainability of water resources that will be studied in this research are related to the current contamination problems of groundwater sources on the island of Tutuila, including identifying sources and their potential contributions. Addressing these problems is an important step towards the design of best-management protection strategies. The specific objectives of this research include identifying potential contamination sources in well capture zones, assessing conditions of wells under the direct influence of surface water, assessing water resources' sustainability under drought and future water uses, and identifying potential land-use impacts to wells, including inputs from soils, fertilizers, cesspools, septic tanks, and piggeries. This effort will include compilation and analysis of available historical and new water quantity and quality data and modeling. New data to be collected includes aquifer information, water levels, and water-quality parameters.

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