You have entered the website of the Water and Environmental Research Institute of the Western Pacific (WERI) at the University of Guam. We are currently six faculty and five staff and our mission is to seek solutions through research, teaching and outreach programs, to issues and problems associated with the location, production, distribution and management of freshwater resources in Guam, the CNMI and the FSM.
Nitrate-nitrogen concentrations in the Northern Guam Lens (NGL) were studied using nitrate-nitrogen data from 147 water wells. Data spanning from January 1978 through December 2000 indicated that concentrations had not neared the United States Environmental Protection Agency's Safe Drinking Water maximum contaminant level of 10 mg/L. However, 39 wells had increasing nitrate-nitrogen trends while nine wells had decreasing trends based on linear regression. Twenty-two wells had maximum nitrate-nitrogen levels between 4 and 4.99 mg/L while six wells had maximum concentrations over 5 mg/L. The Mangilao Subbasin had the highest number of wells with statistically increasing nitrate-nitrogen concentrations. Potential nitrogen sources in northern Guam were identified through aerial and terrestrial investigation. These sources include sewer lines, septic tank/leaching field systems, golf courses, farms, piggeries, fish farms, chicken farms, pastures, and ponding basins.
