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Signal Performance

ATOC PROJECT SCATS DATA

Signal phasing optimisation for three isolated Auckland CBD intersections — SCATS SM + Volume analysis delivered for ATOC

3
Intersections
Auckland CBD, SCATS-managed
6
Critical Phases
DoS > 0.90 before optimisation
5
Phases Resolved
DoS brought below 0.90 threshold
8.1%
Avg DoS Reduction
Across critical approach phases
6.4s
Delay Reduction
Per vehicle, average peak hour
3
Phase Adjustments
Cycle times unchanged
Site Selection
Analysis Period
Chart View
Signal Status
DoS ≤ 0.70 — Stable
DoS 0.71–0.90 — Marginal
DoS > 0.90 — Critical
Green phase
Amber / intergreen
Red (demand waiting)
Data Sources
SCATS SM SCATS VS

Jun–Jul 2024 · 6-week analysis window · 1-min SCATS intervals

Phase Timing Diagram

Signal cycle allocation — Before & After optimisation

ILLUSTRATIVE DATA
SCATS SITE 2141
Upper Queen St / Mayoral Dr
Auckland CBD · Cycle: 90s · 4 phases
Phases — Click to highlight
Hourly DoS — Critical Phase
Before vs After — Degree of Saturation
All phases across all three sites · Peak hour · Critical threshold at 0.90
Delay Reduction by Site
Average vehicle delay (seconds) per approach · AM Peak

Phase-Level Results

Full phase data for all three sites — AM Peak · Green time redistribution and DoS outcomes

Site Phase Movement Green Before Green After Δ Green DoS Before DoS After Δ DoS Delay Before Delay After Δ Delay Status

Methodology

Analysis delivered for ATOC (Auckland Traffic Operations Centre). ML models trained on SCATS SM and SCATS VS data to identify optimal phase timing that minimises degree of saturation across approach phases.

Data

SCATS SMSCATS VS
6-week window Jun–Jul 2024. 1-minute SCATS interval data. Peak periods defined as 07:00–09:00 (AM) and 16:00–18:00 (PM).

Optimisation Objective

Minimise degree of saturation (DoS) on critical approach phases. DoS > 0.90 treated as critical constraint. Cycle times held constant — only green time redistribution applied.

Constraints & Scope

Intersections analysed independently (no corridor coordination). Minimum green times and pedestrian clearance times enforced per AUSTROADS guidelines. Lost-time budget fixed per site.

Other Analytics Dashboards

Auckland CBD Bottleneck

Probe speed + SCATS dual-layer congestion analysis

Speed Violation Heatmap

P85 speed analysis on State Highways

Road Closure Impact

Simulate closures and quantify network delay