Napa County's Conservation Landscape

© Sarah Anne Risk

Napa County's Conservation Landscape

Throughout the Bay Area, the pace of development can move at an alarming rate. However, Napa County, in conjunction with Napa County growers, has done incredible work to proactively protect green spaces of all kinds.

Photo by Sarah Anne Risk


Napa County consists of approximately 506,000 acres in total (748 sq miles).

  • Oak woodland is the most prominent land cover in Napa County, covering over 167,000 acres (33% of the County)
  • The second most common land cover is chaparral/scrub, covering approximately 107,000 acres (about 21% of the County)
  • Coniferous forests cover almost 38,000 acres (7.5% of the County)
  • Grassland covers over 53,700 acres (nearly 11% of the County)
  • Riparian woodlands and forests are more rare, covering just over 11,000 acres (2% of the County)
  • 43,584 producing vineyard acres were reported in 2017 (covering less than 9% of the County)
  • 37,100 acres of land (7.3% of the County) are protected in perpetuity through Conservation Agreements between landowners and the Land Trust of Napa County


Napa County Watershed Information and Conservation Council

2017 Napa County Crop Report

Land Trust of Napa County


True conservation success comes with the need for continual recourse to the goals the community has set to ensure we continue to strike the right balance when envisioning the future of the valley.

Napa Valley Grapegrowers believes that resource conservation and preservation of ag land are inherently linked. To this end, we are proud of Napa County’s foresight in instituting landmark Ag Preserve and Ag Watershed zoning policies as early as 1968, and, subsequently, comprehensive Conservation Regulations by 1991. Napa County’s historic protection of agricultural green spaces, along with these mandates, has set our County up for continual returns when it comes to environmental benefits.

Napa County was the first County in the country to legislate to these high standards that continue to set the gold standard. NVG leadership was supportive of instituting these regulations in 1991 and believes they are integral to maintaining a vital and vibrant agricultural community as we move forward.

Click here for more on Napa County's Ag Preserve


Since 1991, Napa County growers have complied with Napa County’s Conservation Regulations. As of April 9, 2019, the Napa County Board of Supervisors amended the County’s Conservation Regulations with the adoption of the Water Quality and Tree Protection Ordinance (WQTPO), thereby enhancing requirements for stream, wetland, municipal reservoir setbacks, and increasing tree canopy retention and preservation effective May 10, 2019. These regulations include:

  • Stream setbacks scientifically based on slope (25 - 150ft or more)
  • Minimum retention of 70% canopy in Agricultural Watershed (AW) and all municipal watersheds
  • Minimum 40% shrub/brush cover retention in all municipal watersheds
  • Permanent cover cropping on hillsides
  • No earth-disturbing activities between October 15 and April 1 (September 15 and April 1 in municipal watersheds)
  • Preparation of erosion control measures and annual property winterization by October 15 (September 15 in municipal watersheds)
  • Prohibit earthmoving within 500 feet of the Kimball Reservoir and Bell Canyon Reservoir, or within 200 feet of any other sensitive domestic water supply (measuredfrom top of bank).
  • Additional enhanced protections for municipal watershed areas to promote water security
  • All vineyard Erosion Control Plans must be prepared by a state-certified engineer with special local knowledge of Napa County regulations
  • Engineers are required to take a test to qualify to certify vineyard Erosion Control Plans in Napa County
  • Preservation or replacement mitigation at a minimum ratio of 3:1 for removal of vegetation on slopes up to fifty percent; allow preservation or replacement mitigation at a minimum 2:1 ratio within stream setbacks
  • Exemption for agricultural projects of 5 acres or less on slopes less than 30%, limit of once per parcel


Napa County Conservation Regulations

Water Quality & Tree Protection Ordinance (WQTPO)


The following is necessary in order to prepare an ECP:

  • Hiring a state-certified biologist, archaeologist, geotechnical engineer, hydrologist, and other technical experts
  • Identification and survey of native, sensitive, endangered, and protected plant and wildlife species, vernal pools, habitat and more, where-after first avoidance, then mitigation is required
  • Permission from Fish & Game, the Army Corp of Engineers, the Regional Water Quality Control Board

ECPs require documentation for the following:

  • Prevention of erosion and protection of water security
  • Wetlands protection and mitigation including requirement of 50 ft setback from defined wetland
  • Preservation of and protection of sensitive species
  • Groundwater study by a certified hydrogeologist (including well-pumping data and underground geological features) to scientifically prove sustainable water resources and no risk of groundwater overdraft on the property before a project can commence
  • No net increase of groundwater use can occur in the MST, therefore no new vineyard projects are allowed without demonstrating alternative sources for water
  • In groundwater deficient areas, such as the MST, vineyards are restricted to 0.3 acre feet/acre of groundwater use and houses are restricted to 0.5 acre feet/acre groundwater use; this is applicable when any permit is taken out on a property such as for replanting, a new well permit, significant remodeling, or building changes 
  • Regular metering of wells is required (including static water level and gallons used by month) with regular reporting to County Staff


Napa County Website

Napa County Conservation Documents


Napa County’s 2008 General Plan also projects growth/sets limits on growth in different sectors including with reference to vineyard planting:

  • An additional 10,000-12,500 additional vineyards acres were predicted by 2030 by the 2008 General Plan
  • According to Napa County's Planning Department approximately 4500 acres have been planted, which means that no more than 8000 additional acres--at most--will be planted in Napa County
  • Given that vineyard planting is currently increasing at an average rate of less than 1% annually, it is unlikely that the anticipated acreage number will be reached


Napa County General Plan

In addition to County regulations, growers abide by additional state mandates.


  • An EIR is one of the most arduous processes a landowner can undertake, rendering most agricultural projects infeasible, unless large in scale
  • As with ECPs, EIRs require hiring a state-certified biologist, archaeologist, geotechnical engineer, hydrologist, and other experts
  • EIRs must be prepared by an independent third party
  • As with ECPs, EIRs require identification and survey of native, sensitive, endangered, and protected plant and wildlife species, vernal pools, habitat and more, where-after first avoidance, then mitigation is required
  • EIRs always require a tree survey
  • An EIR is generally required for planting on slopes of 30% or greater, and in other specific cases
  • Permission from Fish & Game, the Army Corp of Engineers, the Regional Water Quality Control Board
  • EIRs can take many years of study and many millions of dollars



In addition to the mandates above, as of July 2017, the State Water Board has mandated a new set of requirements for growers in both the Napa and Sonoma Watersheds:

  • Requires farm plans for all vineyard parcels of 5 acres or more certified through Water Board accredited programs
  • All vineyard parcels of 5 acres or more are required to control vineyard sediment and erosion via new mandates applying to sediment, nutrients & pesticides (by 2020)
  • All hillslope vineyard parcels with 5% grade or greater have additional performance standards to control vineyard storm runoff and sediment discharge from roads (by 2023)
  • Requires performance standards for existing unpaved roads on properties containing 5 acres or more planted vineyard (by 2027)
  • Requires establishing and maintaining stream setbacks (as measured from the top of the bank, along all unconfined alluvial channels that are on average greater-than-or-equal-to 1.5 times the bankfull channel width); alternatively, landowners must implement active-or-passive restoration measures through participation in the Rutherford Napa River Restoration, the Oakville to Oak Knoll Napa River Restoration, or the Carneros Creek Adaptive Management Plan


California Water Boards Website


  • For some projects CALFIRE requires Timber Harvest Plans, public notification, environmental review and revegetation
  • Timber Harvest Conversions come with their own set of standards and must also comply with County Conservation Regulations and Performance Standards



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© Copyright 2018 Napa Valley Grapegrowers. This summary has been provided by the Napa Valley Valley Grapegrowers with all data sources cited. Please contact NVG's office with requests to replicate information.