Winery Waste Discharge Requirements (WDRs)


On January 20, 2021, the State Water Resources Control board adopted Resolution No. 2021-0001 for the California Environmental Quality Act Mitigated Negative Declaration for the Waste Discharge Requirements for Winery Process Water and associated General Order. The State Water Board has developed General Waste Discharge Requirements (WDRs), through adoption of Winery Order No. WQ 2021-0002-DWQ, for wineries and other similar facilities with activities related to producing wine that generate winery waste and discharge it to land for reuse or disposal. The ("Winery Order") is a set of requirements that protect water quality from the potential impacts of discharging winery waste to land. 

Winemaking generates process water that has the potential to degrade groundwater quality depending on winery-specific activities, size, and treatment processes. The primary concerns for winery process water that effects groundwater quality are nitrogen, salinity, and biochemical oxygen demand. The Winery Order is applicable statewide and includes requirements to ensure winery operations effectively mitigate adverse impacts to water quality.  This requires wineries producing 10,000 gallons or more per year of process waste that discharges to the land (surface or subsurface), without a separate WDR through Napa County, to enroll in the new Statewide General Winery Discharge by January 20, 2024.

What do Napa County wineries need to do?

Wineries currently enrolled in Napa County’s Winery Waste Discharge Program may be given approval to continue with the program for an additional 3 years. Facilities interested in staying under the Napa County program must apply for the continuation of coverage and receive approval from the Environmental Health department. Applications for Continuation under the Napa County Winery Waste Discharge Program* must be submitted by the August 1, 2023, deadline. The Application is available online at: Application for Continued Enrollment in Napa County Winery Waste Discharge Program

* Enrollees in Napa County's Winery Waste Discharge Program must remain in compliance with the current discharge and reporting requirements. Facilities with above ground discharge shall report quarterly (every 3 months) through the website. Facilities with below ground discharge shall be serviced every six months by a qualified service provider and shall submit reports twice a year (every 6 months) through the website (typically, the service provider for the below ground facilities will fill out the OnlineRME report, however, it is still the responsibility of the facility to ensure Napa County is receiving these reports).

Wineries that do not have a current enrollment in the Napa County Winery Waste Discharge Program are not eligible to apply for continuation and will be required to enroll in the new Statewide General Winery Discharge Program by January 20, 2024. For more information visit the State Water Board site.