What about the MST and Carneros, why aren’t they included? How will we know what’s going on in those areas/subbasins that are already having problems?

The Sustainable Groundwater Management Act requires that Groundwater Sustainability Plans (GSPs) or Alternatives to a GSP be developed for medium and high priority groundwater basins as delineated and ranked by the State Department of Water Resources (DWR). The MST and Carneros Subareas are not state-defined basins, but they are subareas that Napa County has established based on watershed boundaries and the County’s environmental resource planning areas for the purposes of local planning, understanding, and studies. With regards to the MST, it is one of the most monitored areas of the county, with data dating back many decades. There are significant land use controls in place in the area (the county has not approved a discretionary project in the MST that couldn’t meet the “no net increase” standard since 2004), and significant effort has gone into constructing a recycled water pipeline to the area, that became operational in 2016. The Carneros Subarea partly overlaps with the Napa Sonoma Lowlands Subbasin which is a DWR-designated very low priority Subbasin for which a GSP or Alternative is not required. Updates on groundwater conditions in the MST and Carneros Subareas have been and will continue to be included in the County’s Annual Groundwater Monitoring Reports.

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1. What is Sustainable Groundwater Management?
2. What are undesirable results in the context of SGMA?
3. What Groundwater Basins are located in Napa County?
4. Why is the Napa Valley Subbasin subject to Sustainable Groundwater Management Act?
5. Why aren’t the hillsides included? Aren’t they important too?
6. What about the MST and Carneros, why aren’t they included? How will we know what’s going on in those areas/subbasins that are already having problems?
7. Return to the Groundwater FAQ page