The Commission on Water Resource Management's Survey Branch is responsible for collecting basic hydrologic data and conducting water availability and sustainable yield analyses statewide. The information presented below highlights some of the Commission's monitoring activities essential to the protection of Hawaii's water resources. The U.S. Geological Survey also collects water level and deep monitor well data through cooperative agreements with CWRM and other government agencies. The Honolulu Board of Water Supply also has a network of water level and deep monitor wells on Oahu.
A deep monitor well penetrates the freshwater basal aquifer into the underlying brackish and salt water. It is used to estimate the thickness of the freshwater part of the aquifer (freshwater lens) and the freshwater-saltwater transition zone. For convenience, the vertical profile is divided into three parts: the upper fresh water zone (less than 2% sea water), the transition zone (2% to 50% sea water), and into the saline zone (greater than 50% sea water). The data are presented as graphs of the changes in elevation (feet, mean sea level) of the top of the transition zone (2% seawater) and the midpoint of the transition zone (50% seawater) over time.
Deep monitor well Conductivity Data
The Commission on Water Resource Management owns a number of deep monitor wells in the islands of Oahu, Maui, and Hawaii. CWRM staff collects conductivity data for each of these deep monitor wells. Click on the desired well on the maps below to view a time series of the conductivity data collected at the well.
Water level data can be obtained from any well that penetrates the desired aquifer. Water level is the height of water in a well above sea level. Water level data provides information to better understand aquifers.
The graphs below show the changes in water level elevation (feet, mean sea level) over time. These water level data were collected with pressure transducers and data loggers. CWRM staff also collects instantaneous water level data.
Currently, the CWRM staff manages a rain gauge and a fog drip gauge in the island of Hawaii. CWRM staff collects rainfall and fog drip data at the site. Click on the desired location on the map below to view a time series of rainfall and fog drip data collected at the site. Please note that the raingauge at the Naohueleelelua site has been discontinued. The most recent data available for that site is posted for reference.