Traffic Impact Assessments

Traffic Impact Assessment Services

Traffic Impact Assessments (TIAs) are a critical input to planning approvals, infrastructure delivery and development feasibility. For civil engineering firms, land developers, councils and road authorities, a high-quality TIA provides confidence that a proposal can be delivered safely, efficiently and in accordance with statutory and policy requirements.

RSA prepares Traffic Impact Assessments that are practical, proportionate and commercially aware. We understand the pressures faced by project teams — tight timeframes, evolving designs, referral authority scrutiny and the need for clear, defensible advice. Our TIAs are designed to support approvals, reduce risk and integrate seamlessly with broader civil design, planning and road safety outcomes.

Operating nationally across Australia, RSA tailors each assessment to the scale, location and complexity of the project, while maintaining consistency with Austroads guidance and state and local planning frameworks.

What is a Traffic Impact Assessment (TIA)?

A Traffic Impact Assessment is a technical study that examines the transport and traffic implications of a proposed development. It typically considers:

Existing traffic conditions on the surrounding road network
The number, type and timing of vehicle, pedestrian and cyclist trips generated by the proposal
The ability of the existing network to accommodate these additional movements
The safety and operational impacts at access points, intersections and along affected road segments
The need for mitigation measures or infrastructure upgrades

Depending on the nature of the development, a TIA may also address parking provision, servicing and waste collection arrangements, construction traffic, public transport access and active transport connectivity.

Importantly, the scope of a TIA should always be proportionate. Smaller or lower‑risk developments may only require a brief traffic assessment, while major developments, rezonings or complex sites often demand a comprehensive analysis supported by modelling and detailed design advice.

When is a Traffic Impact Assessment required?

Traffic Impact Assessments are commonly required for:

Planning permit applications for medium to large developments
Developments that generate significant traffic or heavy vehicle movements
Proposals accessing arterial roads or high‑speed rural roads
Changes to land use that alter traffic patterns or peak‑period demand
Developments near schools, activity centres or other sensitive road environments
Subdivision layouts and new road connections

Across Australia, TIAs are typically requested by local councils, state road authorities or other referral agencies as part of the planning and development approval process. Clear, well‑structured assessments can significantly reduce requests for further information and help streamline approvals.

Our approach to Traffic Impact Assessments

Our Traffic Impact Assessments are prepared with the end user in mind — whether that is a consulting engineer coordinating approvals, a developer assessing feasibility, or a council or road authority reviewing impacts on the transport network.

RSA’s approach to Traffic Impact Assessments is built on three core principles: safety, clarity and practicality.

Safety‑led analysis

As a specialist road safety consultancy, we view traffic performance and road safety as inseparable. Our TIAs do not focus solely on capacity and delay; they also consider crash risk, conflict points, speed environment, sight distances and the interaction between different road users. This is particularly important in rural and peri‑urban settings, where higher speeds and mixed traffic types can amplify risk.

Clear, decision‑focused reporting

We prepare assessments that are easy for planners, engineers and decision‑makers to understand. Our reports clearly explain assumptions, methods and findings, and they provide unambiguous conclusions and recommendations. Where mitigation is required, we outline practical and achievable measures that align with relevant standards and policy.

Proportionate and pragmatic solutions

Not every development needs major infrastructure upgrades. We work closely with proponents to identify solutions that are fit‑for‑purpose, cost‑effective and defensible. This may include access design refinements, operational changes, staging triggers or monitoring requirements rather than unnecessary capital works.

What our Traffic Impact Assessments include

Our assessments are structured to align with typical planning permit and development application requirements, making them straightforward to review and rely upon.

While each assessment is tailored to the project, our TIAs commonly include:

Site and context review – surrounding land uses, road hierarchy, speed environment and strategic transport objectives
Existing conditions analysis – traffic volumes, intersection performance, crash history and road safety context
Development traffic generation – estimated vehicle, pedestrian and cyclist trips based on accepted industry guidance and local data
Traffic distribution and assignment – how trips are expected to route through the network
Operational assessment – intersection and access performance under existing and future scenarios
Road safety considerations – identification of potential safety risks and treatments to mitigate them
Parking and servicing assessment – adequacy of on‑site provision and impacts on surrounding streets
Mitigation measures – recommended design, operational or infrastructure responses

Where required, we also undertake or peer‑review SIDRA, microsimulation or other modelling to support our conclusions.

Who we work with

RSA delivers Traffic Impact Assessments for a wide range of clients and stakeholders, including:

Civil and traffic engineering consultancies requiring specialist input, peer review or an independent TIA to support multidisciplinary projects
Land developers and project managers seeking clear advice to inform feasibility, staging and approval strategies
Local councils assessing development proposals and their impacts on the local road network
State road authorities reviewing access arrangements, network impacts and safety outcomes on arterial and high-speed roads

We are experienced in working as part of broader project teams and adapting our role to suit the procurement and delivery model.

Integration with other RSA services

Traffic Impact Assessments are often most effective when delivered as part of an integrated suite of services. RSA regularly combines TIAs with:

Road Safety Audits and Safe System assessments
Access design reviews and intersection concept development
Speed management and road function analysis
Construction traffic management advice
Independent peer review of traffic and road safety reports

This integrated approach helps ensure that transport outcomes are not only compliant, but genuinely safe and sustainable over the life of the development.

Experience across urban, regional and rural Australia

RSA has extensive experience preparing Traffic Impact Assessments across metropolitan, regional and rural contexts throughout Australia. We understand that rural councils and road authorities face different challenges to inner‑urban areas, including higher operating speeds, longer sight distances, agricultural vehicles and limited alternative routes.

Our TIAs reflect this context and are informed by a strong understanding of Austroads guidance, state and local planning policy, and network characteristics across Australia. This ensures our advice is robust, defensible and aligned with approval authority expectations.

Supporting smoother planning and approval outcomes

A clear, well-reasoned Traffic Impact Assessment can materially improve approval pathways for all parties involved. For developers and consultants, it reduces redesign, delays and unexpected infrastructure costs. For councils and road authorities, it provides transparent, evidence-based advice to inform decisions and conditions of approval.

By anticipating referral authority concerns, addressing safety issues upfront and providing proportionate mitigation measures, RSA’s TIAs help streamline approvals while protecting the performance and safety of the transport network.

A clear, well‑reasoned Traffic Impact Assessment can materially improve the planning approval process. By anticipating referral authority concerns, addressing safety issues upfront and providing proportionate mitigation measures, our assessments help reduce delays, avoid redesign and give decision‑makers confidence in the proposal.

Whether you are progressing a small infill development or a major strategic project, RSA provides Traffic Impact Assessments that add value, manage risk and support better transport outcomes.

Traffic Impact Assessments