Whangamatā Stormwater Improvement Project

Our contractor, Schick Civil Construction, continues to make solid progress on the Hetherington Road stormwater upgrade despite a number of challenges, including unexpected underground utility conflicts.

The stormwater upgrade works have been largely completed up to the Rutherford Road intersection. Crews are currently waiting on suitable conditions to complete surfacing works (anticipated around Thursday 28 May, subject to weather and timing).

On Monday 11 May, unmarked services were discovered at the edge of the Rutherford Road intersection, crossing the stormwater alignment. Due to its depth, these services must be relocated before pipe installation in that section can proceed. The relocation process is expected to take some time.

To minimise delays, Schick has adapted its approach by “leap-frogging” this section and continuing work toward Port Road. As a result:

• The Rutherford Road intersection can reopen, but will remain unsealed until service relocation can be completed, with Hetherington Road operating under its current single-lane configuration from Port Rd to the Rutherford Rd intersection.
• Crews will return to complete the remaining work once the services have been relocated.

We’d like to acknowledge the Schick team for their proactive, safe and solutions-focused approach in keeping this project moving forward under challenging conditions.

Schick Civil Construction will return to Hetherington Road in the week ending 10 April to begin the second phase of the Stormwater Improvement Project.

This stage will complete the upgrade of the existing stormwater network, replacing pipes with a new 900mm pipeline. That will significantly improve drainage capacity and help reduce surface flooding in the area.

During construction, traffic management will be in place. There will be periods of single‑lane traffic on the northern side of the road, and a temporary detour may be required at times.

Work is expected to be completed by mid‑June 2026.

Thank you for your patience as we finish these important upgrades.

As part of the Stormwater Improvement Project Master Plan our Council has been working with the Whangamatā Stakeholder Community Engagement Team (community representatives, Whangamatā Community Board and Council members) to confirm the next capital works project for stormwater improvement in Whangamatā.

The Hetherington Road Stormwater Improvement project has resulted in additional stormwater improvement options. These additional options will be assessed, alongside our short listed options to confirm the 2026/26 capital works program.

While heavy rain affected much of the Coromandel, the stormwater detention basin pond operated exactly as designed – capturing and releasing stormwater in a control manner to Whangamatā Beach. This helped reduce pressure on upstream pipes and reduced prevented water from pooling in several areas historically prone to surface flooding.

The previous design was a Stormwater Pond, which had not outlet. Simply put, during large rain events, once the pond was full, the stormwater network efficiency was significantly reduced, resulting in surface flooding.

The January weather system was the first major test of the recent stormwater improvement programme, part of a broader multi‑year investment aimed at strengthening Whangamatā’s resilience to severe rainfall. The pond’s effective performance reflects the value of these upgrades and the ongoing work guided by the Whangamatā Stormwater Improvement Project.

Observation of the plants within the basin during the event confirmed they did not prevent the flow of water across the basin. Our Council Water Services Engineers say the results are encouraging and confirm the approach being taken: combining upgraded infrastructure with natural water‑management features to improve both flood protection and environmental outcomes.

Ongoing maintenance of the basin is being undertaken every quarter to maintain the native planting and to remove weeds. Locals may have noticed an infestation of aquatic weeds on the Ocean Road side of the basin. We have involved WRC in the identification of the plants. They have confirmed they are all typical aquatic weeds in our area and none are noxious. Our aim is to support our native species to establish and reduce the impact of aquatic weeds.

Construction on the Hetherington Road stormwater upgrade began July, running from the Martyn Road/Port Road roundabout through to the causeway (Stage 1).

For safety, the Marina walkway was closed during works. The footpath concrete was poured on Thursday 18 September and is expected to re-open by Friday evening, 19 September, just in time for the school holidays.

While some delays occurred due to electricity infrastructure issues, Stage 1 is nearing completion. Stage 2 will soon begin, covering the stretch from the Martyn Road roundabout to the Rutherford Road intersection (see map below). This section will be under a full-time lane closure, with access restricted to residents only.

So far, 180m of new pipe and five manholes have been installed, including a First Defense® High Capacity stormwater treatment system at the outfall. This advanced unit removes sediment, rubbish and hydrocarbons from stormwater, while preventing previously captured pollutants from being re-released.

We appreciate the patience and support of local residents as work continues outside their homes.

Shick Construction crews have made good progress on the stormwater upgrade along Hetherington Road and have been enjoying positive connections with residents and regular walkers passing the site.

The footpath in the reserve linking the Marina and Hetherington Road (next to Breakers Motel) will be closed from Monday 25 August for a few weeks. With construction vehicles moving to and from the compound stockpile area and work happening nearby, it’s simply not safe for the public to use this walkway.

We know this is a busy path, especially in the mornings, and we apologise for any inconvenience while the closure is in place.

This upgrade is part of our six-year programme to improve stormwater network performance and reduce flooding risk. Construction on Hetherington Rd is expected to be completed by summer 2025, and there are also traffic disruptions during this time, so please plan your travel accordingly.

Pictured are representatives from Ngāti Pu, Ngaati Whananga, Ngāti Hako, Ngāti Tamatera and Ngāti Maru, alongside Council Contractors Schick Civil Construction, Metis Consultants and our Council representatives

Work is about to begin on a major stormwater upgrade along Hetherington Road in Whangamatā, as part of our Council’s commitment to long-term resilience and infrastructure improvement.

To mark the start of this significant project, our Council and our contractors, Schick Civil Construction, were joined by local Mana Whenua for an opening karakia and site blessing at dawn on Wednesday 9 July. Following the ceremony, the group gathered back at the office for introductions, a kōrero on the cultural history of the area and a project briefing from the team.

The Hetherington Road stormwater reticulation upgrade is part of our six-year programme to improve performance of the stormwater network and mitigate flooding.

The stormwater improvement works on Hetherington Road in Whangamatā are on track to begin the week commencing 28 July, after a short delay. There have been many months of planning and investigation leading up to this point to make sure power lines in the vicinity of the stormwater pipes have been correctly located and to develop a construction methodology to work safely around the power lines. Our project team has been working with Powerco to ensure the end result provides a long-lasting benefit to the community

Construction work is now expected to be completed by the summer 2025. This may involve significant traffic disruption and people may want to plan their travel accordingly during this period. See details below.

(PDF, 620KB)  

The project involves a full upgrade of the existing stormwater pipeline, running from the Moana Anu Anu Estuary outlet near the causeway through to Port Road. This work will mitigate surface water flooding in the area.The stormwater pipeline has been designed with climate change and sea-level rise in mind. Wa-stops (which prevent seawater from entering the pipe during events such as king tides, while still allowing stormwater to discharge into the marina) will be installed.As part of our on-going efforts to improve stormwater quality, gross pollutant traps (GPTs) will also be installed to capture debris and other pollutants before discharge.

Upgrading the entire network will help enable a series of subsequent capital works upgrades in areas with significant stormwater flood issues, (Casement Road, Tuck Road and Port Road/town center).

This was identified as a priority in the Stormwater Improvement Project Master Plan, which guided how the $2.135 million capital budget for 2024/25 would be allocated.

“This upgrade is an important step toward protecting the Whangamatā community and their property from increasingly severe weather events,” says our Water Services Manager Brett Houston. “We’re committed to completing these essential works efficiently, respectfully and in close partnership with iwi and the local community.”

Temporary traffic management will be in place on Hetherington Road while this work is underway. Construction will take place Monday to Friday, between 7:00am and 6:00pm, with stop-go traffic control and some detours or no-entry zones in place at times. Please plan ahead, allow extra time for travel and follow all on-site traffic management directions. Thank you for your patience as we carry out this important work.

View the Traffic Management Plan here (PDF, 35MB)

As part of addressing the stormwater issues in Whangamatā, our Council has started works at Williamson Park area. The purpose of this project is to drain the upstream network stormwater flows out to sea quickly and without excessive ponding within what was previously the pond and is now the dry basin.

Stormwater quality monitoring was completed between August and November 2024, which confirmed removal of only total suspended solids in the dry basin.

However, the water quality sampling results confirm the incoming stormwater run-off has a low pollutant load, which is representative of the low-density residential catchment. It is also noted that the stormwater run-off quality is improved upstream via the on-lot soakage devices and roadside swales.

The sampling results have confirmed that there is no justification for a full water quality treatment wetland.  As a result, further investigation was completed to determine the contaminant removal of an alternate planted dry detention basin.

The combination of the GPT’s (gross pollutant traps installed at the inlet to the dry basis) and the planted dry basin is predicted to remove 85% of influent total suspended solids (TSS).

Therefore, our Council proposes a planted dry detention basin as the TSS removal and hydraulic residence times meets Waikato Regional Council’s stormwater guidelines and the Whangamatā Comprehensive Stormwater Discharge Consent.

The conversion from a dry to planted detention basin will not require further earthworks. The basin is already regenerating with native river bullrush, tall flat sedge and many-spike flat sedge.

As part of efforts to address stormwater issues in Whangamatā, work has also been carried out in Williamson Park.

In July 2025 over 2,000 native grasses, sedges and flaxes were planted along the basin's banks to stabilise the area and support local biodiversity. Another 3,000 native plants will soon be added within the basin to help filter stormwater run-off. These hardy species were chosen for their resilience in both wet and dry conditions. The planting was a joint effort between our Council and Coastcare, with fantastic support from Ōpoutere School, Craft Haus staff and community volunteers.

Our 2024-34 Long Term Plan (LTP) has been finalised and approved with $9.171M of capital funding granted to address stormwater issues in Whangamatā. Details of stormwater funding can be found on page 69 of the LTP here.

Our Council has been working with the Whangamatā Stakeholder Community Engagement Team (community representatives, Whangamatā Community Board and Council members) regarding these stormwater issues.

We developed a Stormwater Improvement Project Master Plan, which was used to prioritise projects for the $2.135M of capital expenditure available in 2024/25. Using the Stormwater Flood Model, 19 improvement options were generated. The Stakeholders Engagement Team had an input into assessing each option using multiple criteria including;

• Achieving the target level of service
• Proposed location in stormwater network
• Practicality of design
• Relative capital cost
• Level of impact on flooding
• Adaption to climate change

The initial projects selected for 2024/25 were the upgrade of the Hetherington Road and Harbour View Road outlets with larger pipe reticulation, wa-stops (which prevent the backflow of tidal water into the network) and to provide water quality treatment via gross pollutant traps.

However, during detailed design, the survey confirmed the Harbour View Road outlet stormwater sub-catchment is significantly smaller than first anticipated. The flooding experienced in this area is localised, therefore this option benefits fewer properties than initially anticipated.

As result, it has been decided to defer the Harbour View Road outlet and focus on upgrading the Hetherington Road stormwater reticulation. Extending the stormwater pipeline in Hetherington Road provides significant benefit to the surface water flooding experienced within the catchment.

It is proposed to undertake a full upgrade of the stormwater pipeline. This will be designed in separable sections, and it anticipated to extend through to the 2025/26 financial year;

1. Stormwater outlet to Martyn Road roundabout (including a wa-stop and gross pollutant trap)
2. Martyn Road roundabout to Rutherford Road intersection
3. Rutherford Road intersection to Port Road roundabout

Upgrading the entire network is a key enabler for a series of subsequent capital works upgrades in areas with significant stormwater flood issues (Casement Road, Tuck Road and Port Road/town center).