Summary of rice water quality monitoring programs
Monitoring for 2024 has been completed.
The 2024 surface and groundwater monitoring under the RPP and WDR programs was completed in August.
Only one detection of thiobencarb was reported for the entire season under the Rice Pesticide Program (RPP). This result was well below the agricultural drainage target. Additional samples were collected at non-program monitoring sites and yielded similar results. We thank the County Agricultural Commissioner’s offices for their support of the program.
The Rice Waste Discharge Requirements (WDR) surface water program monitored the same two pesticides as last year and obtained similar results below regulatory targets. Pyrethroid monitoring results showed toxicity and acute pyrethroid triggers in several samples from the Upper Colusa Basin Drain. The CRC will continue to work with local industry representatives and the Water Board to improve outreach and ensure compliance.
The Rice Waste Discharge Requirements (WDR) groundwater program reported similarly low nitrate levels in shallow groundwater beneath rice fields. These results further support our Nitrate and initial assessment and technical memos that have shown that slightly Impacts of nitrate leaching from rice fields into shallow groundwater.
We appreciate the industry’s support for regulatory programs and its responsible use of commercial products and protection of the environment.
For more information, contact Craig Riddle, CRC Industry Affairs Manager, at [email protected] or (916) 812-3468.