Water Quality

Thiobencarb Season Ends with Successful Results

Thiobencarb Season Ends with Successful Results

A special thank you to the rice growers, pilots, applicators and PCAs who steward thiobencarb through usage, applications, and recommendations. This season ended with no exceedances. 

We had a high detection number the second week of monitoring, which coincided with a pyrethroid (lambda cyhalothrin) exceedance at the same monitoring site. Additional follow-up is planned with the county agricultural commissioner’s office. 

All total there were eight detections from 70 samples. There were an additional seven samples J-flagged where the result is detected at or greater than the laboratory’s method detection limit (MDL) and less than the minimum reporting level (MRL). The highest detection was at 1.2 µg/L (parts per billion) when the performance goal is 1.5 µg/L in the agricultural drains. All monitoring results at the Sacramento and West Sacramento drinking water intakes were non-detect at a level of <0.2 µg/L.  

The County Agricultural Commissioners, Department of Pesticide Regulation and the Central Valley Water Board add to the stewardship and of managing thiobencarb. However, the true credit goes to the persons using, applying and recommending thiobencarb. Great job all!

For more information, contact the CRC’s Industry Affairs Manager Roberta Firoved at rfiroved@calrice.org or (916) 206-5039.

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Rice Water Quality Programs Monitoring Update

Rice Water Quality Programs Monitoring Update

Monitoring for 2025 is halfway complete.

The 2025 surface water monitoring under the RPP and WDR programs is ongoing.

For the Rice Pesticide Program (RPP), there have been a handful of detections in late May, none of which were above the agricultural drain performance goal.  The latest results from early June were non-detectable.  

The Rice Waste Discharge Requirements (WDR) surface water program is in an assessment year, which means additional sampling for pesticides and toxicity.

Pyrethroids used in rice have been reported in association with water toxicity at the upper Colusa Basin Drain this year for multiple events.  The California Rice Commission (CRC) sent out letters earlier this year requesting the use reporting information (to be submitted in the fall) for pyrethroid users in the area.  Algal water toxicity was reported in the Sacramento Slough near Karnak as well.  

The CRC continues to work on behalf of the industry to conduct required monitoring and interface in reporting with the Water Board.  Additional efforts are underway to assess and analyze water quality trends across the valley and gather information from industry on uses and operational patterns.

We appreciate the industry’s support of the regulatory programs and their good stewardship of the commercial products used and protection of the environment.

For more information, contact the CRC’s Industry Affairs Manager Craig Riddle at criddle@calrice.org.

2025 Water Quality Monitoring Start

2025 Water Quality Monitoring Start

Water Quality Is Our Collective Stewardship

The water quality monitoring under the Rice Pesticide Program (RPP) will begin on April 29th.  The RPP monitors for thiobencarb for 10 consecutive weeks at 4 agricultural drain sites and one site in the Sacramento River near downtown Sacramento.  

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