USGS Water Science Centers are located in each state.
Water Resources of the Pacific Islands
Aloha! Welcome to the USGS Web page for the water resources of Hawaii and the Pacific area. This is your direct link to water-resource information and products for the State of Hawaii, the U.S. Territories of Guam and American Samoa, the U.S. Commonwealth of the Northern Mariana Islands, the Republic of Palau, the Republic of the Marshall Islands, and the Federated States of Micronesia.
Scientific Investigations Report 2015-5010 Spatially Distributed Groundwater Recharge for 2010 Land Cover Estimated Using a Water-Budget Model for the Island of O‘ahu, Hawai‘i.
Scientific Investigations Report 2014-5158 Baseline Water-Quality Sampling to Infer Nutrient and Contaminant Sources at Kaloko-Honokōhau National Historical Park, Island of Hawai‘i, 2009.