> ## Content Index > Fetch the complete content index at: https://airport.mmalc.com/llms.txt > Use this file to discover other available public pages before exploring further. # Sonoma County's airport crossed a threshold requiring Board review seven years ago - URL: https://airport.mmalc.com/review-threshold/ - Published: 2026-08-27T18:07:52.000Z - Updated: 2026-08-31T15:51:17.000Z - Description: Sonoma County's General Plan required a Board of Supervisors review once airport passenger traffic reached 474,500 a year. Airport figures show that threshold crossed in 2019. A county records determination found no responsive record that the review took place. - Author: Malcolm Crawford ## The airport is growing, and the plan for building has not paused Charles M. Schulz–Sonoma County Airport is carrying more passengers than at any point in its history. [Its own published figures](https://sonomacountyairport.org/about-sts/passenger-numbers/?ref=airport.mmalc.com) record 505,157 passengers through July of this year, up more than 10 per cent on the same period in 2025, with July alone accounting for 95,732\. The 2025 total was 780,637\. Airport Manager Jon Stout has described STS as the fastest-growing non-hub airport in the country. On 21 August, the *Press Democrat* [reported](https://www.pressdemocrat.com/2026/08/21/sonoma-county-airport-noise-reduction-expansion-construction-airlines/?ref=airport.mmalc.com) that the airport is mapping out a fifteen-year expansion and modernisation programme, as record traffic strains parking, terminal space and other facilities. Stout had told the Aviation Commission on 20 August that consultants are now coordinating projects previously considered separately: a consolidated rental car facility, parking changes, roadway improvements, new hangars and the relocation of airport offices. Thirteen potential projects around the terminal are in planning, with no adopted phasing or funding commitment for many of them, and each would require its own approvals. At that same meeting, the Commission [endorsed](https://www.pressdemocrat.com/2026/08/20/sonoma-county-airport-commission-backs-noise-reduction-efforts-with-a-price-cut/?ref=airport.mmalc.com) a scaled-back version of the airport's proposed Fly Quiet programme — four components rather than the seven put to it — together with a further round of flight-procedure design work. A motion to recommend the full programme only if the county's general fund paid for it failed. The Commission is advisory; its recommendations go to the Board of Supervisors, expected later this autumn. One meeting, therefore, heard both: a pared-back programme to mitigate the consequences of growth, and a coordinated programme to accommodate fifteen more years of it. ## The General Plan required a review before further growth, not after Sonoma County's General Plan 2020 contains an [Air Transportation Element](https://permitsonoma.org/Microsites/Permit%20Sonoma/Documents/Long%20Range%20Plans/General-Plan-Air-Transportation-Element.pdf?ref=airport.mmalc.com), adopted by the Board of Supervisors in September 2008 and amended in January 2012\. Its Policy AT-5f is short: > A review by the Board of Supervisors shall occur at such a time that the "review threshold" of 650 enplaned air carrier passengers per day averaged over a one year period (474,500 annual passengers) is reached. Objective AT-5.3 fixes the order. The review is to occur prior to any increase in annual passenger or operations levels. In other words, the review was a condition that was supposed to precede further growth, not an assessment to be conducted after the threshold had already been exceeded. Its purpose, both provisions state, is to trigger Board consideration of the environmental and health impacts and infrastructure needs of the airport in relation to its immediate environs. The parenthetical does necessary work. Six hundred and fifty enplanements a day is 237,250 boardings a year, which the policy itself expresses as 474,500 annual passengers — the enplaned-plus-deplaned measure the airport reports monthly. There is no arithmetic route to a higher threshold. The airport's published figures show 488,179 passengers in 2019: the threshold crossed, on the county's own data, seven years ago. Traffic collapsed during the pandemic, recovered past the threshold again in 2022 at 614,481, and has risen every year since to 780,637 in 2025 — more than one and a half times the threshold. The November 2023 Airport Layout Plan quoted AT-5f verbatim and observed that the threshold could have been reached in 2020; the county's own reported total for 2019 had already passed it. This year's 505,157 through July is not an average over a one-year period and so is not itself the trigger, but it continues in the same direction. ## The county says it has no record that the review happened In response to a California Public Records Act request filed by this writer, the Department of Public Infrastructure issued a written determination under Government Code § 7922.535: there are no responsive records of an AT-5f review by the Board of Supervisors. That is a documented agency response to a formal records request, not merely an inference drawn from a silent agenda archive. The county does report to the Board on the airport annually. Those updates cover activity levels, complaints, capital projects and grants. AT-5f and AT-5.3 specify something else: a review of environmental and health impacts and infrastructure needs, triggered by a threshold. On 20 August, this writer wrote to all five Supervisors, copied to the Clerk of the Board, setting out the policy text and the passenger figures and asking the Board to do one of two things: identify the date and agenda item at which the review took place, or schedule it. Publication of this article was held for a week to allow a substantive response. As of publication, none has been received. ## Growth makes the missing review more consequential Aircraft noise from the airport's growing operations has become a significant local concern — significant enough that on 5 August Representative Jared Huffman wrote formally to the FAA Administrator seeking restoration of the pre-2024 departure procedures. Since the [RREHD ONE departure procedure](https://machina.mmalc.com/bohemian-grove/?ref=airport.mmalc.com) took effect in 2024, nearly every southbound departure has been funnelled into a single corridor over West County, and each additional southbound departure using that procedure flies the same corridor over the same communities. The environmental and health questions AT-5f exists to put before the Board become more consequential as traffic grows, whether or not anyone has assessed them in advance. ## The order is the failure The point is not that a number was exceeded. Numbers get exceeded; plans get amended. The plan set a sequence — consider the environmental and health impacts, then grow — and on the documented record it ran the other way. Continuing to build out the airport's programme continues that order: build first, review later, if at all. The review requirement is not the plan's only provision implicated by the building programme. The same section says that improvement projects accommodating air carrier passenger services shall be consistent with 573,000 annual passengers and 15,200 annual operations. Passenger totals have exceeded the passenger figure every year since 2022.\[1\] AT-5e does not categorically prohibit projects; it supplies a consistency standard that covered projects must address. Whether and how that standard applies to the current programme is a separate question, and one the county should answer project by project. The obvious response is that a plan called General Plan 2020 has aged out of relevance. It has not. A general plan remains in force until it is amended or replaced; a planning horizon is not an expiry date, and the county's own 2023 Airport Layout Plan treated AT-5f as a live constraint. The dates in the element are worth reading closely on this point: Objective AT-5.1 carries the phrase "by 2020," while AT-5e and AT-5f carry no date at all. The undated provisions are the ones at issue here. ## AT-5f assigns a reviewer, but not a monitor How a requirement in an adopted plan comes to be unmet without anyone deciding to ignore it is visible in the drafting. AT-5f names a threshold and it names a decision-maker. It stops there. Nothing in the policy assigns an office to track passenger volume against the figure, requires that volume to be reported against it, or specifies how the review is to be placed on the Board's agenda once the figure is passed. Nor do the element's implementation programmes supply what the policy omits, and this is the telling part, because those programmes do assign responsibility elsewhere. The element closes with five of them, each naming a responsible body and the policy it implements: the Airport Division for maintaining the Master Plan, for the Approach Protection Plan, and for the noise complaint and reporting programme; the Airport Land Use Commission for reviewing its own land use plan; the planning department for an airport protection combining district. None of the five implements AT-5f. The element takes care to assign someone to report noise complaints to the Board every year. It assigns nobody to notice that the passenger threshold has been crossed. That is a defect of drafting rather than of intent, and it is the kind of defect a general plan update exists to repair. None of this requires anyone to have acted in bad faith. It requires only that a policy adopted in 2008, amended in 2012 and quoted as a live constraint in 2023 be applied as written — and that its successor be written so that applying it does not depend on someone happening to look. --- ## What readers can do now *The existing review obligation and its successor policy present two different tasks. The Board can identify or schedule the missing AT-5f review now. Through the General Plan update, the county can ensure that the successor policy names a responsible office, requires reporting against its threshold, and triggers Board review automatically. Written comments may be sent to the Board of Supervisors at* [*bos@sonomacounty.gov*](mailto:bos@sonomacounty.gov) *and to the General Plan team at* [*GeneralPlan@SonomaCounty.gov*](mailto:GeneralPlan@SonomaCounty.gov)*.* [*My own submission is here*](https://airport.mmalc.com/general-plan-sonoma-submission-august-2026/)*. The next scheduled Board opportunity is the General Plan Workshop/Noise Policy on 15 September 2026.* --- *This article was researched and drafted in collaboration with Claude, Anthropic's AI model.* --- 1. Objective AT-5.1 and Policy AT-5e, Air Transportation Element §5.5\. Passenger totals were 614,481 in 2022, 641,178 in 2023, 772,758 in 2024 and 780,637 in 2025\. ↩︎