Source: HCM-aligned practice + accumulated review pain. When to use: existing AND future scenarios, every submittal.
Volumes & demand
- Volumes match count sheets/balancing figure exactly (spot 3 nodes); AM/PM not swapped
- PHF: measured for existing (per approach if agency wants); future per agency policy — SOURCED, not default 0.92 by habit
- Heavy vehicle % from counts; growth applied per memo Geometry & lanes
- Lanes/storage/taper = field/plan truth (Street View pass); storage lengths real, not defaults
- Lane utilization, shared/exclusive assignments sane; RTOR allowed only where legal/geometry supports Signals
- Existing timing = timing sheet (cycle, splits, offsets, ref phase, recalls, ped times + walk/FDW) — cite sheet date
- Coordinated? reference phase & offsets consistent along corridor; actuated params (min/max/passage) not left at defaults for existing
- Future timing method stated (optimized? capped cycle? agency policy?) Model settings
- Ideal sat flow, area type, link speeds per agency/HCM basis; HCM vs Percentile results — reporting the one the agency asked for
- Unserved/spillback flags reviewed — a pretty LOS with unmet demand is fiction Outputs
- Report exports match tables in the doc (no stale re-runs); queues: source labeled (Turn Lane and Queue Checks)
- File hygiene: scenario naming, one change-log note per version Free companions: FHWA Traffic Analysis Toolbox — Volume III calibration/validation thresholds are what a reviewer cites when your SimTraffic queues face scrutiny; earlier volumes cover picking the right tool before defaulting to Synchro. Practice question: delay dropped 20 s between v3 and v4 with “no changes” — list the six settings you diff first. QA/QC reminder: your name goes on the assumptions page; if a setting isn’t sourced, it’s not done.