8 YEARS EXPERIENCE
Jen Wen Gan
Project Manager / Transport Planner
§ Service 006 · Traffic Engineering
Traffic Engineering
Geometric design of intersections (signalised, roundabouts, priority), active-mode and safety improvements, speed-management interventions, road furniture and signage design, and Safe System Audits (SSA) of detailed designs.
Who it's for
- NZTA Waka Kotahi
- Local councils
- Developers
The problem we solve
An intersection or corridor designed without rigour — capacity, safety, all modes, the standards — fails its users or fails its audit. Treatment has to work for the movement and stand up to a Safe System lens, not just fit on the drawing.
TTAP designs intersections, safety and active-mode improvements and speed-management treatments to the standards, tested for capacity and audited for safety — so the design works on the ground and survives review.
What's included
- Intersection geometric design (signals, roundabouts, priority)
- Active-mode & safety improvements
- Speed-management interventions
- Signing & road-furniture design
- SIDRA capacity & performance assessment
- Safe System Audits (SSA)
What you get
- Geometric design of signalised, roundabout and priority intersections
- Active-mode and safety improvement design
- Speed-management intervention design
- Signing and marking / road-furniture design
- SIDRA capacity and performance assessment
- Safe System Audits of detailed designs
How we work
- 01
Assess
We assess the movement, the safety history and the constraints across all modes before a line goes on the page.
- 02
Design
We design the geometry, treatment and signing to NZTA and Austroads standards.
- 03
Test & audit
We test capacity in SIDRA and run a Safe System lens over the design to catch the risks early.
- 04
Document for delivery
We produce a buildable, auditable design pack with swept paths, signing and marking.
Standards
- NZTA Traffic Control Devices (TCD) manual
- Austroads Guide to Road Design
- Land Transport Rule: Traffic Control Devices
- Safe System approach
Tools
- SIDRA Intersection / Networks
- AutoTURN / vehicle swept paths
- CAD
Relevant projects
Who leads this work
Frequently asked
Can you do the Safe System Audit as well as the design?
We do both — though on a given project we'll keep the audit independent of the design where that independence matters. Bringing a Safe System lens in early, before detailed design locks in, is usually where it adds the most.
Do you design for active modes and not just vehicles?
Yes — active-mode and safety improvements are core to what we do, designed as part of the intersection or corridor rather than bolted on afterwards.
Can you check an intersection's capacity before we commit to an option?
Yes. SIDRA capacity and performance assessment up front tells you whether an option works before you spend on detailed design — often the cheapest check you can make.