Surface Water Ambient Monitoring Program (SWAMP)

• Lower American River Bacteria Study: Learn about the bacteria source study and view monitoring results from previous years.
• Recreational Water Quality Monitoring: Learn about the watersheds being monitored and see the most recent results.
• Harmful Algal Blooms: Learn about the Central Valley Water Board’s work to address harmful algal bloom (HABs).

• Program Overview
• Central Valley Regional SWAMP Activities
• Reports
• Data Access and Portals

Central Valley SWAMP Overview

• Annual Report Video for FY 23/24 (Video will open in YouTube)
• Program Overview information for Surface Water Ambient Monitoring Program (SWAMP)

About SWAMP

The Surface Water Ambient Monitoring Program (SWAMP) is tasked with assessing water quality in all of California's surface waters. The program conducts monitoring directly and through collaborative partnerships, and provides numerous information products, all designed to support water resource management in California. Find out more on the overall program available resources at the State Water Board's SWAMP website, including:

• The SWAMP Mission
• SWAMP IQ: Information Management and Quality Assurance Center
• Statewide Monitoring Programs
• Clean Water Team: Citizen Monitoring Program

Current Monitoring Projects:

SWAMP's current monitoring focuses on monitoring E. coli as an indicator of potential fecal pollution to track whether water quality supports swimming and other recreational uses. During the summer, weekly water quality samples are collected from beaches and recreational areas along select waterways. For more information on active monitoring projects, please visit the Recreational Water Quality Monitoring webpage.

Information on Pre 2015 SWAMP Studies:

• Webinar on Central Valley SWAMP Activities (May 6, 2010)
• Region-wide Studies
• Sacramento-San Joaquin River Delta
• Sacramento River Basin
• San Joaquin River Basin
• Tulare Lake Basin

Water Quality Reports & Fact Sheets

• Biointegrity and Eutrophication Technical Reports
  

  The Central Valley Water Board supported preparation by the Southern California Coastal Water Research Project of technical reports on biological health and indicators of eutrophication in Central Valley streams, lakes and reservoirs. Measures of biological health include stream invertebrate and algae communities in wadeable streams and chlorophyll and cyanotoxins in lakes and reservoirs. Concentrations of nitrogen and phosphorous were used to assess risks of eutrophication (also called biostimulation). For more information, please contact Janis Cooke at Janis.Cooke@waterboards.ca.gov

  • A Technical Foundation for Biointegrity and Eutrophication Indicators and Thresholds for Modified Channels, Intermittent Streams and Streams on the Central Valley Floor (2025)
  • Central Valley Water Board Cover Letter to Accompany the Modified Channels Technical Report
  • Central Valley Lakes and Reservoirs Eutrophication Assessment (2025)

• Central Valley SWAMP Water Quality Reports
• Historical Water Quality Reports (pre-2000)
• Additional SWAMP Reports

• CEDEN: The California Environmental Data Exchange Network integrates data from SWAMP and other Water Board programs.
• California Open Data Portal: Hosts open data collected by the state in a format that is easy to search, download, and combine.
• Water Data Library: Provides access to water quality data collected by the Department of Water Resources, including the Sacramento Watershed Coordinated Monitoring Program.
  • To download grab sample data, go to Data by Station Group and select "SWCMP" for a list of Sacramento Watershed stations.
  • To download continuous temperature data, go to Continuous Data and search by Station Number or Station Name.
• My Water Quality Portals