The fire arrives
before Cedar St. clears

Cedar's throat carries 314 vehicles. The Ventura Ave junction carries 653, because 195 dwellings reach Seneca via Cameron without ever touching Cedar. Seneca's two-lane half-mile buffer holds about 210 vehicles — a real cushion, and still not enough. Under gridlocked conditions it fills in roughly 25 minutes, and from that moment Cedar's discharge is governed from a half mile downstream. Every junction-capacity number upstream stops mattering.

Two clearance times are worth keeping separate, and conflating them is the easiest way to misread this analysis. Cedar corridor clearance is the last Cedar-origin vehicle reaching Ventura Ave — the headline figure on this page. Whole-catchment clearance is the last of all 653 vehicles passing the outlet. Under the severe blockage stress test the second is roughly 5.3 hours for the existing neighbourhood alone and 7 hours with the project, and neither figure is the time to reach safety.

This has a consequence that cuts against the project's own proposed mitigations. Relieving Cedar — by removing parking, by opening the School Canyon gate — moves vehicles to the outlet faster without widening it. Parallel paths into a single constrained junction do not add capacity. They change which street the queue stands on.

The two junctions are in series, so only the tighter one governs — and which one that is depends on Ventura Ave. Under night and dense smoke with gaps available on Ventura Ave, tightening the Cedar-at-Seneca right turn from free-flowing to backed-up nearly doubles clearance, from 76 to 134 minutes. Under gridlock the same change moves the result by about thirteen minutes on four hundred — indistinguishable from noise. When the outlet fails, nothing upstream of it is worth fixing. That is worth knowing before anyone proposes striping, signage or parking removal on Cedar as mitigation.

This is the honest reading, and it is worth stating plainly because the applicant will otherwise state half of it. Under Thomas Fire conditions — night, dense smoke, Ventura Ave gridlocked — the 63 existing dwellings that feed Cedar Street take about 2.6 hours to get their last vehicle to Ventura Ave without any project at all, and the full 258-dwelling Seneca catchment takes roughly 5.3 hours to finish passing the outlet. That is not the project's doing.

What the project does is add roughly four hours to that under the same conditions, and between 47 and 61 minutes even when Ventura Ave has gaps. A pre-existing deficiency is not a defense: CEQA cumulative-impact analysis exists precisely for a project that makes an already-significant condition substantially worse. It also bears directly on the finding required to grant a density-bonus incentive — that there is no specific adverse impact on public health and safety for which no feasible mitigation exists. The feasible mitigation is named in the City's own General Plan.

Spreading departures over thirty minutes instead of fifteen has two opposing effects: it lowers the peak arrival rate, which helps, and it puts the last household on the road fifteen minutes later, which hurts. Which wins is a diagnostic.

When Ventura Ave has gaps, the slower window is 3.5 minutes worse — the corridor was keeping up, so the only thing that changed is that the last vehicle started later. When Ventura Ave is gridlocked, the slower window is 15 minutes better, because peak demand never mattered; the outlet was serving at a fixed rate the whole time and arriving earlier only meant waiting longer.

That asymmetry is worth stating plainly to a decision-maker: under the conditions that matter, warning people sooner does not get them out faster. Earlier warning is valuable — it is simply not a mitigation for an outlet that cannot pass the traffic.

Wildfire evacuations happen at night and in smoke. The Thomas Fire reached Ventura after dark. Low visibility reduces junction capacity by roughly 10 to 12 percent in the Highway Capacity Manual's weather adjustments, and darkness compounds it. Moving from daylight and light smoke to night and dense smoke costs the corridor 19 minutes when Ventura Ave has gaps and 68 minutes when it is gridlocked.

Any analysis that models a clear weekday afternoon is modelling the condition under which evacuation is least likely to be needed.

The severe blockage case in this analysis no longer rests on a neighbour's recollection. Appendix B of Ventura's own General Plan — the Emergency Evacuation Analysis prepared by Rincon Consultants in April 2024 under SB 99 and AB 747 — models a wildfire originating in the city's northern hillsides. That is this project's scenario. Its findings for the road this corridor drains onto:

Two things follow. First, the outlet this neighbourhood depends on is already over capacity on a normal weekday evening, before any fire and before this project. Second, in the City's own wildfire scenario it is over capacity for two miles — and that scenario also lists North Ventura Avenue among its roadway closures north of the fire, concentrating everything southbound.

That allows the outlet capacity to be derived rather than assumed. The City's analysis uses 1,900 vehicles per lane per hour as ideal arterial flow; Ventura Ave is three lanes at Seneca. Applying standard gap-acceptance capacity to a minor-street left turn merging into that flow:

This reverses the direction of the criticism this analysis expected. The 120 veh/hr setting is generous, not pessimistic. It implicitly assumes courtesy gaps or active traffic control. At the volumes the City's own document projects, an unsignalised left turn out of Seneca has no meaningful capacity at all.

The City's evacuation strategy list, in the same appendix, recommends "minimize left-turn movements along evacuation routes and on roads leading to evacuation routes" and establishing traffic control points staffed by emergency management personnel. Neither is proposed for Seneca and Ventura Ave, and nothing in this project provides either.

Only 142 measured feet of Cedar St — five cars — sits between the project boundary and the Alabama St junction. Everything beyond the fifth vehicle stands inside Vello Retreat, on the 26-foot internal streets that must be posted and kept clear as fire apparatus access. Peak queues in this model run 2,975 to 4,375 feet depending on conditions — roughly 2,830 to 4,230 feet of standing traffic inside the development. Without the project the queue north of Alabama is zero feet in every single cell, because no dwellings front that stretch of Cedar.

Cedar itself measures 29 feet 10 inches curb to curb, re-measured on site in September 2026. That is the width of the whole run from Seneca St up to Alabama St — walked end to end, with no narrower section anywhere along it. What matters for an evacuation is not the curb-to-curb figure but what is left to drive through. Where two neighbours park opposite each other — a full-size pickup at 8 ft 6 in and a large van at 8 ft 2 in, both mirror to mirror — the clear travelled way is 13 feet 2 inches.

The California Fire Code sets a 20-foot minimum unobstructed width for required fire apparatus access roads. Whether and how that provision applies to this existing public segment is a determination for the Ventura Fire Department, and one worth asking them to make on the record — the measured condition sits 6 ft 10 in, or 34%, below that floor. At 13 feet 2 inches a Type 1 engine cannot pass a stopped passenger car: it is short by about a foot on the body and three feet mirror to mirror. Title 14 CCR §1273.00 requires roads to serve emergency equipment and civilian evacuation concurrently. Here they cannot.

This is a screening-level analysis prepared by a resident, not a certified traffic impact study. It uses a simplified queuing representation rather than a calibrated microsimulation. It does not model route choice beyond the corridor, driver heterogeneity, towed vehicles, pedestrian evacuees, phased zone releases, or active traffic management by police — all of which a real evacuation would involve, some helping and some hurting.

Three inputs carry most of the uncertainty and none of them are the model's engine: the 258-dwelling Seneca catchment, the Ventura Ave gridlock rate, and vehicles per household. Two of the three rest on resident accounts. They should be verified before any of these numbers are relied upon.

This work began before the Draft MND was released. The applicant's Evacuation Analysis (Appendix I, April 2026) has since been published, and it does not reach the question this page was built to ask. It computes clearance times for two segments of North Ventura Avenue, north and south of Seneca. Cedar Street is not a study segment — its entire treatment is one sentence describing the local streets as operating under low traffic conditions. No turning-movement counts have been taken at Seneca and Ventura Ave, the junction this whole catchment must pass through, and no analysis in the record combines the full Seneca catchment with the project at that junction.

Where the two analyses do overlap, they are not far apart. Appendix I uses an effective capacity of 631.65 veh/hr on a three-lane arterial; this model assumes 600 veh/hr at a stop-controlled residential junction. Appendix I derives 194 to 291 project vehicles; this model uses 204. Appendix K, the applicant's fire protection plan, models a rate of spread of 580 ft/min under a 50 mph wind — 6.59 mph, or roughly thirteen percent of wind speed. Its second scenario works out to about seven percent. The ten-percent rule this page previously used sits between them, and the fire-arrival figures now come from Appendix K directly rather than from any rule. Both analyses produce corridor clearance times measured in hours.

The purpose of this page is narrower than prediction: to show that the corridor's evacuation performance is governed by an outlet nobody has analysed, and that this is answerable with arithmetic that is not yet on the record. If a calibrated study reaches different numbers, that study should supersede this one. The point is that one should exist before the Planning Commission acts.