USGS is conducting Aquifer Recharge and Water-Budget study for the San Juan Islands
The United States Geological Service in cooperation with San Juan County Health and Community Services is working on a study of aquifer recharge and water-budget components. San Juan County Council was briefed on the study during its February 28, 2023 meeting. The power point presentation is posted online.
There are numerous maps included this one showing water use divided into three categories. Public Supply that includes Group A and B water systems (dark blue in the map), Self Supply domestic wells (in gold); and Irrigated Agricultural land (in black). Preliminary water use estimates by category are Public Supply 65%; Self supply domestic 33%, Agriculture 2%.
The per capita water use is approximately 65 gallons per day.
According to USGS, there is an ongoing need for an accounting of water budget components and water use estimates.The goal of the study is to provide an updated water balance.
• Task 1: Evaluate available groundwater, surface water, and meteorological data.
• Task 2: Complete recharge estimations
• Task 3: Compile and estimate water use and provide an updated water balance.
This graphic shows the recharge areas. The darker the color the more water recharged.
The concerns about possible future changes include:
•Increased water use
•Climate change
•Extended summer dry season
•Heavier winter rains
•Rising sea levels
