Oahu NAWQA Home 

Study Unit Description

Surface Water

Bed Sediment and Tissue

Aquatic Ecology

Ground Water

Liaison Committee

Publications

U.S. Geological Survey 

USGS Water Resources Division 

USGS: Water Resources of Hawaii 

USGS NAWQA Program

Online searchable database of national NAWQA Data

 

In 1991 the U.S. Geological Survey initiated the National Water-Quality Assessment (NAWQA) Program to assess the status and trends in the quality of freshwater streams and aquifers, and to provide a sound understanding of the natural and human factors that affect the quality of these resources. As part of the program, investigations were conducted in 51 areas-- called "study units" -- throughout the Nation to provide a framework for national and regional water-quality assessment. Together, these areas account for 60 to 70 percent of the Nation's water use and population served by public water supplies, and cover about one-half of the land area of the Nation.

NAWQA study units

As part of the NAWQA Program, the USGS has been evaluating water-quality conditions on the island of Oahu, Hawaii. Water resources are of significant economic and ecological importance to the island. Ground water provides essentially all municipal and domestic water for a large and expanding population, while streams provide important riparian and instream habitats for many threatened and endangered species. In addition, streams affect the physical, chemical, and aesthetic quality of receiving waters, such as estuaries, bays, and nearshore waters which are critical to the tourism-based economy of the island.

Ala Wai Canal -- view of Diamond Head and Waikiki  (photo by Douglas Peebles).

Beginning in October 1998, and continuing for a period of 3 years, the NAWQA Program intensively investigated the quality of water resources on the island of Oahu, Hawaii. The largest and most important component of the intensive-study phase was an "Occurrence and Distribution Assessment". The goal of this assessment was to characterize, in a nationally consistent manner, the broad-scale geographic and seasonal variations of water quality related to major contaminant sources and background conditions.