Sonoma County releases ‘capacity threshold study’ on wine-related events

A just-released study on wine-related events finds that poor roads and loose permitting leads to traffic woes during seasonal events.|

Traffic Studies for Winery Events

To address capacity and safety issues related to the increased traffic volumes, the County of Sonoma retained GHD to conduct the following traffic studies:

Dry Creek Valley & Westside Road Capacity Threshold Study (PDF: 29 MB)

Sonoma Valley Capacity Threshold Study (PDF: 13.3 MB)

Background Conditions Report (PDF: 5.1 MB)

The impact of large-scale winery events has been among Sonoma Valley’s biggest ongoing issues for years – community workshops and town halls have been held, and the Board of Supervisors held at least one lively public hearing on the topic of unchecked winery growth. In July, 2016, the Board of Supervisors asked the county permitting department – Permit Sonoma – to come up with draft ordinances to regulate the wine industry’s events, tasting room and food service guidelines.

That was before the October 2017 wildfires scorched Sonoma Valley, pushing the impact of such winery events temporarily out of the headlines.

But in the intervening two years, those issues have not gone away – winery traffic foremost, but also parking, whether such events are agricultural or strictly marketing, and the impact of the industry on rural character.

Those issues resurfaced last week with the long-delayed release of a report from Permit Sonoma, revisiting the litany of issues that the lucrative wine business brings to Sonoma Valley, and the rest of the county at large. A follow up report is due this week, one which takes a first stab at recommendations to deal with the problems raised by the “Sonoma Valley Capacity Threshold Study” from the engineering firm of GHD.

The study looked at highly-trafficked areas in Sonoma Valley, including Highway 12, Arnold Drive, East Napa Street and Napa Road, Watmaugh Road and others. The focus was on the impact of weekend events, especially during peak season – defined in the report as July to September – and non-peak seasons.

Major industry-wide events and other large weekend events evaluated in the study include Savor Sonoma Valley, Signature Sonoma Valley, Taste of Sonoma, Sonoma Valley Crush, the Sonoma Wine Auction and the Valley of the Moon Vintage Festival, as well as smaller-scale winery happenings such as Gay Wine Weekend and the Holiday Open House.

Non-winery events, including those at the Sonoma Raceway, were also included.

“It’s something that I think the county needs to get a handle on; they’ve just been going along with each application, bending … to accommodate the different trends in the industry,” said Kathy Pons of Kenwood, a member of the Preserve Rural Sonoma County steering committee.

She pointed out that 20 years ago, events were not permitted on agricultural land, where many wineries are now located that take part in industry-wide events and wine weekends throughout the year.

The greater part of the report is concerned with traffic patterns, with often troubling conclusions. At several points the study mentions that “many of the County-maintained roads in the study area are built below typical modern design standards, and lack shoulders, sidewalks, or designated bike lanes,” limitations that negatively impact the Valley’s ability to withstand large events.

Additionally, the study counts 11 fatal traffic accidents between 2011 and 2015 in the study area, with Arnold Drive having the highest occurrence of injury-related collisions.

But such concerns and risks are not confined to large events, according to the study.

“Traffic levels on Sonoma Valley roadways can reach unacceptable levels on any given day of the year, regardless of seasonal fluctuations or wine-related events,” notes the GHD report, though industry-wide events – as well as heavy rain and flooding affected roadway closures and traffic patterns – can all contribute to the challenges of vehicular travel in Sonoma Valley.

The initial Threshold Capacity Study includes 12 recommendations for traffic operations and safety, community engagement and management of event travel. Many of the recommendations focus on improvements to roads, driveways and other transportation-related solutions. One of the recommendations calls for a shuttle bus plan to support these larger events, of more than 2,000 participants, to minimize traffic impact.

Recommendations also include limiting industry-wide events to no more than two in one month, and move some from the Peak Season (June-September) to Off-Peak Season (October-May). Currently, September alone sees Taste of Sonoma/Wine Country Weekend, Sonoma Valley Crush, the Sonoma Valley Wine Auction and Valley of the Moon Vintage Festival.

Moving one or more of these to October or another season, the study suggests, would “allow intermittent relief to the community of additional traffic impacts created by large wine events.”

A separate document, the Draft Sonoma Valley Winery Events Guidelines, will be released on Nov. 14, prepared by Permit Sonoma staff and other stakeholder groups. It will be reviewed at a Sonoma Valley Citizens Advisory Commission (SVCAC) meeting on Wednesday, Nov. 20, in the Sonoma Valley Veterans Memorial Building. That report is expected to focus more closely on specific zoning and permitting proposals to rein in winery events.

With 125 wineries in Sonoma Valley, and 450 in the unincorporated county as a whole, the impact of the industry remains significant and, given its contributions to the local economy, difficult to fully control, according to the Permit Sonoma report.

The SVCAC usually meets on the fourth Wednesday of the month, but with Thanksgiving following that date this November, Supervisor Susan Gorin’s office has requested the Wednesday, Nov. 20 date “to ensure robust participation.” The venue will be the Sonoma Valley Veterans Memorial Building Auditorium, 126 First St. W., and the meeting will begin at 6:30 p.m.

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Traffic Studies for Winery Events

To address capacity and safety issues related to the increased traffic volumes, the County of Sonoma retained GHD to conduct the following traffic studies:

Dry Creek Valley & Westside Road Capacity Threshold Study (PDF: 29 MB)

Sonoma Valley Capacity Threshold Study (PDF: 13.3 MB)

Background Conditions Report (PDF: 5.1 MB)

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