Speed Violation Heatmap

Network Coverage

segments · — km monitored

—

Avg Violation Rate

network-wide · current time period

—

High-Risk Segments

violation rate > 35%

—

Safety Risk Index

VKT × violation rate (daily weighted)

Metric

Time of Day

8:00 AM

Morning Peak

12a6a12p6p11p

Speed Zone

Highway

Legend — Violation Rate

0 – 10%

10 – 20%

20 – 30%

30 – 40%

40 – 50%

> 50%

● DEMO DATA

TomTom Probe Data · 5 Aug 2024 · South Island SH Network

Click a corridor on the map to explore detailed speed analytics

Highest-Risk Corridors

Ranked by Safety Risk Index (daily VKT × violation rate) · showing filtered results

Top 10

#	Corridor	Hwy	Limit	V85	Violation Rate	Safety Risk

Data & Methodology

Speed violation analysis derived from TomTom probe vehicle GPS traces, aggregated per corridor segment and hour. Based on the methodology developed by RoadInsite for NZTA corridor safety assessments.

Violation Rate

Interpolated from speed percentile distribution. The percentile rank at which vehicle speed equals the posted limit defines the violation threshold.

VR = 1 − P(speed ≤ limit)

Safety Risk Index

Volume-weighted risk combining traffic exposure with speed behaviour. High-volume corridors with high violation rates represent the greatest safety priority.

Risk = VKT × Violation Rate

V85 Speed

The 85th percentile speed is the industry-standard design benchmark. Where V85 exceeds the posted speed limit, systematic speeding is confirmed across the corridor.

V85 > Limit → systemic issue

Data source: TomTom probe vehicle data · 10% penetration rate assumed · Volume = sample × 10 expansion factor · Demonstration dataset: 5 August 2024

Highest-Risk Corridors

Data & Methodology

Other Engineering Tools

Route Distance

Level of Service

Queue Length

Sight Distance