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Required Site Specific Studies for Wineries

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In addition to the Use Permit Application Requirements, the typical site specific studies and information that are required for a Use Permit application for a winery are provided below. Applicants contract with qualified professionals and consulting firms to prepare these studies. The individual professionals and/or consulting firms need to be contacted to receive estimates for the preparation of these studies.

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Archaeological/Cultural Resources Report

Assembly Bill (AB) 52 established a consultation process with all California Native American Tribes on the Native American Heritage Commission List. Tribal Cultural Resources must be taken into consideration in the determination of project impacts and mitigation. Per AB 52, tribes that are traditionally and culturally affiliated to the Sonoma County requested that the County of Sonoma (lead agency for projects located within the incorporated area of Sonoma County) provide formal notification to the tribes of proposed projects in the tribes’ area of traditional and cultural affiliation.

Permit Sonoma treats AB 52 formal notification of the proposed project as a referral and provides the AB 52 referral to the designated contact of the traditionally and culturally affiliated tribes in Sonoma County when a project application is submitted. The referral notice includes a brief description of the proposed project, the proposed project location, and copies of other project documents submitted with the application. The tribe must respond, in writing, within 30 days of receipt of the formal notification to request consultation and/or request that an archaeological/cultural resources report be submitted to the tribe. The assigned project planner will notify the applicant if an archaeological/cultural resources report and/or consultation is requested when a tribe’s response to the referral is provided within the required 30-day response period.  All environmental review documents related to California Native American cultural resources and the proposed project site are confidential and are not available to the public to prevent looting, vandalism or damage to a tribal cultural resource.

If there is the potential for cultural resources on the property where a proposed project is located, consultation may be requested by a tribe, alternatives or avoidance evaluated, mitigation measures developed, and monitoring by a tribal member during earth-moving activities required. If mitigation measures are agreed upon with a tribe, the measures must be recommended for inclusion in the environmental document and their implementation may be required in the project’s Conditions of

Architectural Plans

When an application for a Use Permit is for a winery, the following additional information is requested on the preliminary architectural plans listed under Use Permit Application Requirements (link provided above). Floor plans for all buildings, caves, pavilions, etc. should be provided. They should be detailed with dimensions, square footages, and uses for all rooms and use areas. Square footages need to be provided for areas included in the project:

  • tasting room
  • case good storage
  • indoor wine barrel storage
  • outdoor wine barrel storage
  • crush pad
  • outdoor tank area
  • indoor tank area
  • production area
  • restrooms
  • wine glass cleaning/sterilizing
  • lab
  • offices
  • and any other use related to the proposed winery

Biotic Resource Assessment (BRA)

The biologist needs to provide the information as to whether the project would:

  1. Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service.
  2. Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Wildlife or U.S. Fish and Wildlife Service.
  3. Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means.
  4. Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites.
  5. Conflict with any local policies or ordinances protecting biological resources, such as tree preservation policy or ordinance.
  6. Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan.

If a Biotic Resource Assessment (BRA) is required, the biologist must have the following qualifications:

  • Experience in the identification of habitats and vegetation associations found in Sonoma County;
  • Familiarity with local plant and animal species, including all listed species;
  • Familiarity with the critical and/or sensitive habitats within which listed species are likely to be found;
  • Familiarity with applicable state and federal statutes and procedures related to plant and animal  surveys and collection.

The BRA should include the physical and biological setting; project description including the Assessment Area with a 100-foot buffer; background data review; field survey methodology; a description of any potential sensitive or special status species that has the potential to occur and sufficient rationale for why the species would not be present; description of how the project will not impact riparian or wetland habitats, or other listed species habitat either directly or indirectly; site maps and vegetation/habitat maps; site topography; and mitigation measures to reduce any impacts to less-than-significant.

Food Service

Allowable food service is determined on a site specific basis as established in the Use Permit subject to the following limitations:

  1. Retail sales of pre-packaged local food products may be permitted only during tasting room hours.
    1. Retail sales of pre-packaged local food products.
    2. No indoor seating area or table service is permitted in conjunction with retail sales of pre-packaged food. Outdoor seating areas are permitted for use as outdoor picnic areas.
    3. No off-site signs advertising retail sales of food is permitted. All project signage shall conform to the Zoning Code Sign Regulations.
  2. Samples or tastes of pre-packaged local food products, such as crackers, nuts or other palette cleansers offered in conjunction with wine tasting.
  3. Prepared meals or appetizers featuring local food products offered in conjunction with agricultural promotional events, such as wine club parties, and winemaker dinners, and agricultural promotional activities during normal business hours.
  4. Food and Wine Pairing featuring local food products may occur during normal tasting room hours and must be permitted after tasting room hours.

A Use Permit application for a winery must indicate if food is proposed to be served to the public and the type of facilities proposed for food service, the square footage of the area for food service, the number of seats or persons that can be served, and the hours of operation.

Greenhouse Gas (GHG) Emissions and Air Pollutant Emissions Analysis

The County concurs with the significance thresholds that Bay Area Air Quality Management District (BAAQMD) staff have recommended for projects other than stationary sources. The greenhouse gas (GHG) significance threshold is 1,100 metric tons per year of CO2e or 4.6 metric tons of CO2e per service population (residents and employees) per year. These thresholds are supported by substantial evidence for the reasons stated by BAAQMD staff.

While the project’s GHG emissions are most likely less than the significance threshold of 1,100 MT CO2e/year, used by the BAAQMD, the County has committed to reducing emissions to the maximum extent feasible by implementing all reasonably feasible measures and best available technologies to further reduce greenhouse gas emissions.

The County’s adopted goals and policies include General Plan Policy OSRC-14.4 to reduce greenhouse gas emissions 25% below 1990 levels by 2015. Sonoma County emissions in 2015 were 9% below 1990 levels, while the countywide population grew 4%. In May 2018, the Board of Supervisors adopted a Resolution of Intent to Reduce Greenhouse Gas Emissions that included adoption of the Regional Climate Protection Agency’s goal to further reduce greenhouse gas emissions by 40% below 1990 levels by 2030 and by 80% below 1990 levels by 2050. The Resolution of Intent included specific measures that can further reduce GHG emissions. All new development is required to evaluate all reasonably feasible measures to reduce GHG emissions and enhance carbon sequestration.

The project plans should include reasonably feasible measures to reduce GHG emissions in the design, construction, and long-term operations of the project. The assigned Project Planner will work with the applicant on the appropriate measures to be implemented. If an existing facility is requesting a Use Permit modification and some GHG emissions reduction measures are already being incorporated, description of them should be included in the application.

The measures chosen to be implemented should be incorporated into the project plans and a description of them submitted as part of the application so they can be included in the environmental analysis in the greenhouse gas section of the CEQA document. If measures are not incorporated into the project, then a Greenhouse Gas Reduction Plan that defines measures to reduce greenhouse gas emissions in the design, construction, and long-term operations of the project will be required as a mitigation measure and condition of approval.

An air pollutant emissions analysis should be included with the greenhouse gas emissions analysis since this information will also be required for the preparation of the CEQA document. An air quality consultant can conduct both analyses.

Hydrogeologic Study

Policy 8-1-14 outlines requirements for hydrogeologic reports, including well pump tests, for discretionary and ministerial projects performed for the purpose of complying with Sonoma County General Plan Policy WR-2e and sustainable groundwater management.

Policy WR-2e (formerly RC-3h): Require proof of groundwater with a sufficient yield and quality to support proposed uses in Class 3 and 4 water areas. Require test wells or the establishment of community water systems in Class 4 water areas. Test wells may be required in Class 3 areas. Deny discretionary applications in Class 3 and 4 areas unless a hydrogeologic report establishes that groundwater quality and quantity are adequate and will not be adversely impacted by the cumulative amount of development and uses allowed in the area, so that the proposed use will not cause or exacerbate an overdraft condition in a groundwater basin or subbasin. Procedures for proving adequate groundwater should consider groundwater overdraft, land subsidence, saltwater intrusion, and the expense of such study in relation to the water needs of the project.

A hydrogeologic report will be required when a project is located in a Class 3 and/or Class 4 groundwater availability area and also within priority groundwater basins. Planning Policy 8-1-14, Procedures for Groundwater Analysis and Hydrogeologic Reports, is provided in Permit Sonoma's Policies and Procedures.

Marketing Plan/Promotional Activities and Events

A marketing plan must be submitted for Use Permits for wineries or tasting rooms that describes the industry-wide events, agriculture promotional events and/or other types of marketing activities plus their scale and intensity including:

  1. The number of events, maximum number of people, the season, and the timeline (weekend or weekday, daytime or evening) for all types of agricultural promotional events and industry-wide events;
  2. The number of events, maximum number of people, the season, and the timeline (weekend or weekday, daytime or evening) for all types of non-agricultural events, such as charitable or political fundraisers. The maximum number of annual non-agricultural events is four (4).
  3. The number of events, maximum number of people, the season, and the timeline (weekend or weekday, daytime or evening) for all wine dinners.
  4. The seating area in square feet, number of seats and the frequency (times per day and days of week) for food and wine pairing.

The Marketing Plan should include a table summarizing the type of activity or the type of event, number of events per month and year, hours of operation, maximum number of guests, number of employees, type of food service, and outdoor use areas and whether music or amplified sound is proposed.

Noise Study

The General Plan Noise Element calls for the preparation of an acoustical analysis or noise analysis (collectively Noise Analysis), prior to approval of any discretionary project involving a potentially significant new noise source or a noise sensitive land use in a noise impacted area. These Guidelines serve as a tool to implement the General Plan Noise Element policies by providing the following: 1) criteria to determine when a Noise Analysis is required; 2) minimum qualifications for persons preparing a Noise Analysis; and 3) substantive requirements for a Noise Analysis, including format content, standards, and thresholds of significance.

Table NE-2 in the Noise Element applies to non-transportation noise, which includes all project noise except the noise which occurs on public roads and highways. All proposed winery events and activities must be analyzed. Event noise shall not exceed the adjusted Daytime General Plan Noise Standards listed in Table NE-2 as measured from the exterior property line of any adjoining noise sensitive land use or residential zone. An additional adjustment of -5 dBA is required where the noise source exceeds the ambient by 10 or more decibels.

The Guidelines for the Preparation of Noise Analysis PDF Document is provided in Permit Sonoma's Environmental Review Guidelines.

Septic Capacity

Policy 9-2-31 applies to wineries that are requesting agricultural promotional events and/or industry-wide events in the Use Permit application. The intent of this policy is to provide sizing criteria for on-site disposal systems that are commensurate with the number and size of the events approved under the facility's permit.

Generally, this policy requires larger disposal systems as the number and size of permitted events increases. The policy also seeks to avoid over-sizing disposal systems based on a relatively small number of large events; therefore, this policy allows the four largest approved events to be serviced completely with portable toilets.

As the number of approved events increases, the on-site wastewater system disposal capacity requirements increase based upon a percentage of the size of the fifth largest special event flow. See Table A in Well & Septic Policy 9-2-31, Sizing of Onsite Wastewater Disposal Systems for Special EventsAuthorized by Use Permits and the Use of Portable Toilets, provided in Permit Sonoma's Policies and Procedures.

Traffic Impact Study (TIS)

The impact of any proposed development on transportation system performance, whether it is small or large, depends on the number of trips generated by the proposed development, the location of the connection(s) to the transportation system, and the routes taken to and from the site. This impact is quantified by preparing a Traffic Impact Study (TIS).

Traffic Impact Studies must be conducted in accordance with County standards, as detailed in the Guidelines for Traffic Impact Studies PDF Document provided on the Transportation & Public Works' Traffic Impact Study Guidelines page.

If the project is located on a State highway, the TIS must be peer reviewed by the County’s peer review consultant.

On December 28, 2018, regulatory changes to the CEQA Guidelines that implement Senate Bill (SB) 743 were approved. SB 743 creates a process to change the way that transportation impacts are analyzed under CEQA. Measurements of transportation impacts will include “vehicle miles traveled” (VMT) instead of auto delay, as measured by “level of service” (LOS) and other similar metrics. The California Natural Resources Agency has certified and adopted changes to the CEQA Guidelines that identify VMT as the most appropriate metric to evaluate a project’s transportation impacts. To achieve the State’s long-term climate goals, California needs to reduce per capita VMT through VMT mitigation. Employing VMT as the metric of transportation impact statewide will help to ensure GHG reductions planned under Senate Bill (SB) 375 will be achieved. SB 375 directs the California Air Resources Board to set regional targets for reducing greenhouse gas emissions.

Lead agencies (such as County of Sonoma) have the discretion to set and apply their own thresholds of significance for SB 743. The County of Sonoma had to set its thresholds of significance by July 1, 2020, the statewide implementation date deadline. The TIS Guidelines will be revised to reflect the use of VMT and the thresholds to evaluate a project’s transportation impacts. A public workshop will most likely occur for education and discussion of VMT as the required metric for a TIS.

Traffic Management Plan

A new winery or tasting room must prepare a traffic management plan for events with over 100 participants.

  1. Parking attendants are required each day of the event.
  2. An effective shuttle plan and system is required to support each day of the event. A convenient and secure “park and ride” area must be provided.
  3. The on-site parking requirements must be met.
  4. All parking and queuing of traffic must be located on the winery/tasting room premises.
  5. On-street parking must be prohibited. The winery must enforce the on-street parking restrictions.
  6. Large Tour buses are not allowed.

Visual Assessment

The purpose of this administrative procedure is to provide guidelines for the assessment of visual impacts in the preparation of Initial Studies and Environmental Impact Reports. These guidelines provide procedures to guide staff and consultants in preparing and analyzing visual impacts. While the analysis of visual impacts involves qualitative judgments, this procedure is intended to define a methodology that utilizes to the extent practicable, objective standards that can be described and utilized in a consistent manner.

View the Visual Assessment Guidelines

Water Use Report

The purpose of Policy 8-1-3 is to provide groundwater monitoring guidelines for commercial and industrial projects requiring a Use Permit. All commercial and industrial projects, includes wineries, which rely on water wells and require a Use Permit shall include a proposed groundwater use estimate prepared by a civil engineer or registered geologist as part of the project application. Projects using less than 0.5 acre-fee/year are “Small Commercial and Industrial Projects.” Projects using greater than 0.5 acre-feet/year, but less than 5 acre-feet/year, are “Large Commercial and Industrial Projects.” Projects using greater than 5 acre-feet/year are “Very Large Commercial and Industrial Projects.”

Tasks necessary to implement this policy:

  1. The application shall include an engineer’s estimate of water use by the proposed project.
  2. Conditions will be added to project approvals requiring groundwater monitoring, reporting, easements, and monitoring wells as specified. Additional conditions may be added to project approvals specifying the quantity of groundwater use approved.
  3. Groundwater monitoring reports shall be submitted annually to the Project Review Division at PRMD between January 1 and January 31 of each year. Violations of project Approval Conditions shall be forwarded to Code Enforcement.
  4. The Project Review Division shall conduct quality control site inspections to collect verifying water meter readings and, if applicable, monitoring well groundwater level measurements. The target goal is to collect verifying data on 5 percent of the subject sites per year.

Planning Policy 8-1-3, Monitoring Guidelines for Large Capacity Water Wells Pursuant to General Plan Policy WR-2d (formerly RC-3b), is provided in Permit Sonoma's Policies and Procedures.