Publications

Ground-water recharge is estimated from a monthly water budget calculated using long-term average rainfall and streamflow data, synthesized pan-evaporation data, and soil characteristics. The water-budget components are defined seasonally, through the use of monthly data, and spatially by geohydrologic areas, through the use of a geographic information system model. The long-term average...

The Regional Aquifer-System Analysis (RASA) Program of the U.S. Geological Survey was initiated in 1978 and was completed in 1995. The purpose of this program was to define the regional geohydrology and establish a framework of background information on geology, hydrology, and geochemistry of the Nation's important aquifer systems. This information is critically needed to develop an...

Ground-water recharge is estimated as the residual component of a monthly water budget calculated using soil characteristics and long-term average rainfall, streamflow, irrigation, and pan-evaporation data. The water-budget components of rainfall, direct runoff, evapotranspiration, and ground-water recharge are defined seasonally, through the use of monthly data, and spatially by land...

In 1992, the U.S. Geological Survey ground-water data-collection program in the State of Hawaii consisted of 188 wells distributed among the islands of Oahu, Kauai, Maui, Molokai, and Hawaii. Water-level and water-quality (temperature, specific conductance, and chloride concentration) data were collected from observation wells, deep monitoring wells that penetrate the zone of transition...

The ‘I‘iwi is one of the most spectacular of extant Hawaiian birds, with vermilion plumage, black wings and tail, and long, decurved bill. In pre-European Hawai‘i, beautiful feather capes, sometimes containing hundreds of thousands of ‘I‘iwi feathers, were a symbol of power and prestige among native Hawaiians. The ‘I‘iwi is a bird of the Hawaiian forests. Its decurved bill seems well...

This report documents the results of an evaluation of the surface-water quantity, surface-water quality, and rainfall data-collection programs in Hawaii. Fourteen specific issues and related goals were identified for the surface-water quantity program and a geographic information systems (GIS) data base was developed summarizing information for all surface-water stream gages that have...

Detailed water budgets calculated for southern and southeastern Oahu are used with a geographic information system to develop simplified methods for estimating areal water budgets for predevelopment and mid-1980's land use. The methods were applied to estimate water budgets for the Waianae area of western Oahu, and for north-central, southern, and southeastern Oahu. A water budget was...

The island of Oahu, Hawaii, is the eroded remnant of two coalesced shield volcanoes, the Waianae Volcano and the Koolau Volcano. Shield-building lavas emanated mainly from the rift zones of the volcanoes. Subaerial eruptions of the Waianae Volcano occurred between 3.9 and 2.5 million years ago, and eruptions of the Koolau Volcano occurred between 2.6 and 1.8 million years ago. The...

The coastal plain in the Ewa area of southwestern Oahu, Hawaii, is part of a larger, nearly continuous sedimentary coastal plain along Oahu's southern coast. The coastal sediments are collectively known as caprock because they impede the free discharge of ground water from the underlying volcanic aquifers. The caprock is a layered sedimentary system consisting of interbedded marine and...

Concern over potential effects from construction of the H-3 highway on Oahu, Hawaii, prompted a long-term study of streamflow and suspended-sediment transport at a network of five stream-gaging stations along the highway route. This report presents results for 1983-91, which included pre-construction and construction periods at all stream-gaging stations. Annual rainfall, streamflow, and

Ground-water recharge is estimated as the residual component of a monthly water budget calculated using long-term average rainfall, streamflow, irrigation, pan-evaporation data, and soil characteristics. The water-budget components are defined seasonally, through the use of monthly data, and spatially by topographic and geologic areas, through the use of a geographic information system...

Oahu, the third largest of the Hawaiian islands, is formed by the eroded remnants of two elongated shield volcanoes with broad, low profiles. Weathering and erosion have modified the original domed surfaces of the volcanoes, leaving a landscape of deep valleys and steep interfluvial ridges in the interior highlands. The Koolau Range in eastern Oahu and the Waianae Range in western Oahu...