Basin Monitoring

As part of Sustainable Groundwater Management Act (SGMA) compliance requirements, SMGWA works with its members and other local agencies to monitor groundwater levels, groundwater quality and streamflow conditions in the Santa Margarita Groundwater Basin (Basin). 

By each April, SMGWA issues an Annual Report on Basin conditions as required by SGMA. The Annual Report summarizes groundwater elevation and groundwater quality trends, while streamflow information is summarized in separate reports that are provided below.

Groundwater Level Monitoring

The Basin currently has a network of 40 wells that are monitored at least twice each year. The network includes seven monitoring wells installed in 2023 to increase the current understanding and assess future conditions of the Basin. Funding for the monitoring wells installed in 2023 was provided in part from the Water Quality, Supply, and Infrastructure Improvement Act of 2014 and the Parks, Environment, and Water Bond of 2018 through an agreement with the Department of Water Resources (DWR).

Water level data from the full monitoring network is submitted to DWR twice each year by January 1st and July 1st. Once submitted, the data is available to the public on the DWR site in the form of a hydrograph and a table of data. The map below shows the locations and the aquifers being monitored by each well. The list of wells below the map includes a link to the well on the DWR site.  Wells in bold are used for evaluating sustainable management criteria for water levels in the Basin. Wells in the table without a link have not yet been added to the DWR site, but they will be soon.

         

 

Local Well NameFormation Monitored
Local Well NameFormation Monitored
MHA #1Santa Margarita/Lompico
SVWD #15 MWLompico/Butano
MHA #2Lompico
SVWD #3BMonterey/Lompico/Butano
MHA #3Lompico
SVWD #9Monterey
MHA-MW1Lompico
SVWD AB303 MW-1Santa Margarita
SLVWD Olympia #2Santa Margarita
SVWD AB303 MW-2Lompico
SLVWD Olympia #3Santa Margarita
SVWD AB303 MW-3ALompico
SLVWD Pasatiempo #1Lompico
SVWD AB303 MW-3BSanta Margarita
SLVWD Pasatiempo #2Santa Margarita
SVWD Canham WellButano
SLVWD Pasatiempo #5ALompico
SVWD Orchard WellLompico/Butano
SLVWD Pasatiempo #7Lompico
SVWD Stonewood WellButano
SLVWD Pasatiempo #8Lompico
SVWD SV4-MWSanta Margarita
SLVWD Quail #4ASanta Margarita
SVWD TW-18Santa Margarita
SLVWD Quail #5ASanta Margarita
SVWD TW-19Lompico
SLVWD Quail MW-ASanta Margarita
SMGWA-2Lompico/Butano
SLVWD Quail MW-BSanta Margarita
SMGWA-3Santa Margarita
SLVWD Quail MW-CSanta Margarita
SMGWA-4Santa Margarita
SVWD #10Santa Margarita/Lompico
SMGWA-5Santa Margarita
SVWD #10ALompico
SMGWA-6Santa Margarita
SVWD #11ALompico
SMGWA-7Monterey
SVWD #11BLompico
SMGWA-8Monterey

Streamflow Monitoring

Click here to see real-time monitoring on Bean Creek near Mackenzie Creek

Santa Margarita Basin Streamflow Monitoring, Dry Season 2023

Santa Margarita Basin Streamflow Monitoring, Dry Season 2022 (Graphs Only)

Santa Margarita Basin Streamflow Monitoring, Dry Season 2021

Santa Margarita Basin Streamflow Monitoring, Dry Season 2020

Eagle Creek Hydrogeological Reconnaissance, Summer of Water Years 2018 - 2020

Bean and Lower Zayante Creek Accretion Assessment, Water Year 2019 

San Lorenzo River Longitudinal Accretion Report, Water Year 2019

San Lorenzo River Longitudinal Accretion Report, Water Year 2017