Key facts about this subbasin
Location boundaries: bounded by Sonoma Mountain on the west and the Mayacamas Mountains on the east. South of Kenwood and north of and adjacent to San Pablo Bay
Principal sources of groundwater recharge: precipitation and infiltration on the valley floor and streambed recharge from Sonoma Creek and its tributaries to the shallow aquifer
Decades or longer: estimated length of time it takes to recharge the deep aquifer
44,000 acres: land covered by the subbasin, including the City of Sonoma and the communities of Schellville, Buena Vista, El Verano, The Springs and Glen Ellen and unincorporated rural areas
- 13% Urban community areas
- 44% Agricultural areas
- 43% Native vegetation and surface water areas
Acreage by crop types in the basin (not limited to groundwater-irrigated)
- Citrus & subtropical: 20.1 acres
- Deciduous fruits & nuts: 28.3 acres
- Grain: 6,679.6 acres
- Pasture: 195 acres
- Truck nursery & berry: 29.8 acres
- Vineyard: 8,193.4 acres
- Idle or unknown: 1,628.9 acres
- Turf irrigation: 190.1 acres
1,148 acre-feet: Estimated groundwater crop irrigation offset per year by alternative water sources (recycled water, surface water)
8,500: how many acres of crops and vines depend on groundwater for irrigation in Sonoma Valley
12,720: number of parcels in the subbasin
2,095: approximate number of groundwater dependent parcels (note, these numbers do not include those connected to a public water system, and some parcels have more than one use)
- 1711: Residential
- 136: Commercial
- 652: Agricultural
- 62: Turf
5,000: estimated number of people in the Sonoma Valley GSA subbasin that rely solely on groundwater for drinking and other basic water needs.
< 200 ft: depth of most wells in the shallow aquifer
~200-800 ft: typical depth of wells in the deep aquifer wells
116: number of groundwater-level monitoring wells located in the subbasin and contributing watershed
Status of Conditions
Status of Conditions defined by the Sustainable Groundwater Management Act that the GSA is actively addressing via the implementation of projects and programs in the Groundwater Sustainability Plan:
- Land Subsidence: no evidence for concerns
- Groundwater quality: no evidence for concerns
- Interconnected surface water: more data needed
- Seawater intrusion: more data needed
- Reduction of storage: concerns
- Lowering of groundwater levels: concerns
Want to learn more?
Visit our website to access the Groundwater Sustainability Plan and find detailed information on the status of this work to manage groundwater resources in our Annual Report.
Join in the community-wide effort to support sustainable groundwater with one of our community programs:
LEVEL UP! – Voluntary Well Monitoring, Flow Smart – Voluntary Flow – Metering, and Well Aware – tools for building local groundwater sustainability.
Click the image to view infographic in a pdf