Showground Road and Carrington Road Intersection Upgrade – Economic Appraisal

Icon of a front-facing bus with windows and headlights.

Client: Transport for NSW

Industry: Transport

Capabilities: Economic Modelling Cost-Benefit Analysis 

The Challenge

The intersection at Showground Road and Carrington Road in Castle Hill was facing mounting pressure from increased traffic volumes and limited infrastructure capacity. Transport for NSW identified this location as a priority within its Bus Priority Infrastructure Program, which aims to improve public transport reliability and reduce congestion across key urban corridors. The intersection’s existing layout lacked dedicated bus lanes and suffered from inefficient traffic flow, leading to delays and unreliable bus service, particularly during peak periods. These issues were compounded by safety concerns for all road users, including pedestrians and cyclists. With the opening of the Sydney Metro Northwest, the need for better integration between road and public transport networks became more urgent. The proposed upgrade sought to address these challenges by improving connectivity, enhancing safety, and supporting more efficient transport operations in the area.

The Action

Polis Partners in conjunction with Iceni conducted a detailed economic appraisal to assess the benefits of the proposed upgrade. The analysis focused on:

  • travel time savings through improved traffic flow
  • reduced vehicle operating costs from lower fuel use and wear
  • crash cost savings via safer intersection design and pedestrian upgrades
  • better public transport access through stronger links to Sydney metro northwest.

The cost-benefit analysis followed Transport for NSW’s Economic Evaluation Guidelines, incorporating both capital and operating costs to assess the project’s overall value.

The Results

The appraisal confirmed that the intersection upgrade would deliver a net benefit to the NSW Government and the wider community. It supported the business case for investment by demonstrating improvements in transport reliability, road safety, and congestion reduction. The project will enhance long-term transport efficiency in Castle Hill and aligns with government priorities for sustainable, integrated urban mobility.