Reconnecting Patoka with purpose

WSP partnered with HDC to deliver a sustainable, cost-effective culvert rebuild using recycled materials, modern fish passage design, and community collaboration.

Location

Hawke's Bay, New Zealand

Client

Hastings District Council (HDC)

Project Value

Project value

Project Status

Completed

Project overview

The Patoka Culvert Rebuild has restored vital connections for the rural community of Patoka, following the devastation of Cyclone Gabrielle. Commissioned by Hastings District Council (HDC), the project is rebuilding a key culvert and Hendley Road—ensuring residents are reconnected and the community is future-ready.

Client brief: Resilient, sustainable solutions

HDC engaged WSP to deliver a comprehensive culvert rebuild, with a focus on sustainability and cost-effectiveness. The brief called for the reuse of surplus materials—including Polyethylene Culvert Pipe sections from another cyclone recovery project—to halve material costs and reduce waste. The new design also needed to meet modern fish passage standards and involve the local community and Mana Whenua throughout planning and delivery.

Project challenges: Building back better, together

Delivering this project meant overcoming a unique set of challenges:

• Material Reuse: Repurposing surplus culvert pipe and recycling aggregate from the temporary access road.
• Ecological Standards: Designing a larger culvert and a steep upstream tie-in to restore fish passage and stabilise the site.
• Community Engagement: Collaborating closely with local residents, Mana Whenua, and landowners to ensure a community-led approach.
• Weather: Navigating tough winter conditions to keep the project on track.

Our response: Smart engineering, local insight

WSP’s multidisciplinary team brought together geotechnical, structural, hydrology, hydraulic, transport, procurement, contract management and ecology expertise all lead through Client Side Project Management to deliver:

• Innovative Material Reuse: Working with Hicks’s Bros Ltd, the team recycled aggregate from the temporary road for the new pavement—minimising waste and costs.
• Ecological Innovation: In partnership with NIWA, Hawkes Bay Regional Council, and Mana Whenua, WSP designed a novel fish ladder and a culvert that meets today’s ecological standards.
• Community Collaboration: WSP supported HDC in engaging the community and Mana Whenua through meetings and a community day, with native planting plans shaped by local input.
• Enhanced delivery of similar projects across the rebuild: The lessons learnt, and opportunities found that could be utilised across the rebuild package has already gone into other projects, further reducing construction cost, design fees and program.

The outcome: A stronger, more connected Patoka

Despite challenging weather, the project remained on track and was open to public on the 5th of September 2025. The new culvert restores fish passage, strengthens resilience, and reconnects Hendley Road residents. The collaborative approach has built lasting relationships with the community and Mana Whenua.

Client benefits: Sustainable, community-focused results

• Cost Savings: Smart material reuse and recycling delivered significant savings.
• Ecological Gains: The new culvert and fish ladder restore stream health and stability, while the extensive native planting further enhances the water quality of the awa.
• Community Ownership: Active involvement of locals and Mana Whenua fostered pride and partnership.
• Resilient Infrastructure: The rebuilt culvert and road are ready to withstand future storms.

Leading with purpose: Engineering for community and environment

The Patoka Culvert Rebuild reflects WSP’s commitment to innovative, sustainable, and community-first engineering. By reconnecting Patoka and restoring the Mangahina Stream, we’re helping Hastings District thrive—today and for generations to come.