Sonoma Valley Groundwater - Voluntary Groundwater Level Monitoring Program

    Home | Basin Advisory Panel | Documents | Meetings | Monitoring

    The long-term groundwater-level monitoring program for the GMP was developed in the 2007 Plan, initially implemented in 2008, and has expanded in terms of the number of monitored wells. The Voluntary Groundwater Level Monitoring Program currently comprises over 140 wells in Sonoma Valley. Expansion of the program has been accomplished mainly through public outreach and education to private well owners who have volunteered their wells for groundwater-level monitoring. The voluntary monitoring program includes a combination of:

    • Privately-owned domestic and agricultural irrigation water-supply wells
    • Community and public water-supply wells
    • Dedicated groundwater monitoring wells

    The monitoring program does not measure or record how much water is pumped from wells, only the depth (elevation) of the groundwater surface. All collected data is managed by the Sonoma County Water Agency and is used to create maps indicating groundwater levels. Personal information, such as the owners name, address and specific well details, are not published and only the general locations and depths of the wells are displayed on maps prepared for the GMP.

    The information obtained from the Voluntary Groundwater-Level Monitoring Program has been extremely useful in improving the understanding of groundwater level fluctuations and trends within Sonoma Valley. The groundwater-level monitoring program is a critically important component of the GMP and serves as a foundation to develop and improve decision-analysis tools, identify and forecast trends and guide the design, implementation and monitoring of groundwater management and protection programs.


    Surface Water and Groundwater Interaction Monitoring (Seepage Runs)

    Synoptic streamflow measurements (seepage runs) have been conducted on Sonoma Creek and its tributaries routinely since 2014. These seepage runs consist of a series of streamflow measurements made at multiple sites over a short time period (e.g., single day to several days) along Sonoma Creek and its tributaries to quantify streamflow gains and losses for a specific time period.  The information obtained from this program is used to refine gains and losses along reaches of Sonoma Creek, spatially and temporally, in the MODFLOW model, providing an improved understanding of recharge mechanisms in the valley.  The field data is collected by staff of the Sonoma Ecology Center and Sonoma County Water Agency.  Results of the seepage runs are included in Annual Reports and are available on the Sonoma Ecology Center’s Knowledge Base website.