Ewen Street, Takapuna, Auckland

**Client:** Frontline Projects (on behalf of the homeowner)
**Location:** Takapuna, Auckland
**System:** FloodFree Concealed Flood Barrier
**Barrier Width:** 3,932mm
**Barrier Height:** 500mm

Concealed Flood Protection for a Residential Basement Carpark

Project Overview

Following previous flooding events that impacted a residential basement carpark in Takapuna, the homeowner engaged Frontline Projects to deliver a permanent flood mitigation solution capable of protecting the property from future stormwater ingress.

Watersmart was engaged to supply, install, commission, and test a FloodFree Concealed Flood Barrier system, providing automatic flood protection while maintaining the appearance and functionality of the existing driveway.

The completed installation protects a 3.9 metre wide driveway entrance and was designed to withstand a 300mm flood level with an additional 200mm of freeboard. The project incorporated an upstream strip drain, reinforced concrete pit integration, and submersible pump arrangement to ensure reliable operation during storm events.

The Challenge

The basement carpark had previously experienced flooding during heavy rainfall events, with stormwater entering the property through the driveway access.

The homeowner required a solution that would not only prevent future flooding but also integrate seamlessly into the residential environment.

Key project requirements included:

Maintaining unrestricted vehicle access during normal conditions

Providing automatic protection without manual deployment

Operating independently of external power supplies

Remaining visually discreet within the driveway

Delivering reliable protection even when the property was unattended

Avoiding large or intrusive flood infrastructure

Without intervention, the property remained vulnerable to recurring flood damage, disruption to residents, vehicle damage, and ongoing remediation costs.

The Solution

After evaluating available options, the FloodFree Concealed Flood Barrier was selected as the most suitable solution for the site.

Unlike traditional flood barriers that require manual deployment or create a permanent visual presence, the FloodFree system remains concealed beneath the driveway surface during normal operation. When floodwaters rise beyond the drainage system's discharge capacity, the barrier automatically deploys using buoyancy principles, creating a watertight seal across the driveway entrance.

Because the system operates passively, it requires no external power source and no human intervention during a storm event.

Manufactured from marine-grade aluminium, the barrier remains fully trafficable during normal use while providing dependable flood protection when required. The system is designed to withstand Class G medium traffic loads of up to 10 tonnes GVM while remaining concealed beneath the driveway surface.

Delivery and Installation

While Frontline Projects completed the civil works and structural preparation, Watersmart was responsible for the specialist supply, installation, commissioning, and testing of the flood barrier system.

The project scope included:

Procurement of the custom-manufactured AWMA FloodFree barrier system

Installation of the outer and inner cassette assemblies

Integration with reinforced concrete pit structures

Installation of sealing interfaces and drainage connections

Functional flood testing and commissioning

Final quality assurance inspections and handover documentation

Throughout the installation, Watersmart worked closely with Frontline Projects to ensure the barrier was correctly aligned, fully integrated with the drainage infrastructure, and operating as intended.

Extensive commissioning and flood testing were completed prior to handover to verify barrier deployment, seal performance, pump operation, drainage functionality, and overall system readiness.

Planning and Design Considerations

Flood barrier projects are highly site-specific, with system design and installation requirements varying based on flood levels, barrier dimensions, drainage infrastructure, civil works, and access constraints.

While every project is different, early assessment of flood risk and site conditions is critical to developing an effective and reliable solution. Watersmart works closely with property owners, engineers, and contractors to ensure flood protection systems are appropriately designed, integrated, tested, and maintained for long-term performance.

For high-value assets such as basement carparks, building entrances, critical infrastructure, and commercial facilities, concealed flood barriers can form part of a broader resilience strategy, helping reduce the risk of future flood damage and operational disruption.

Ongoing Servicing and Warranty

Like any critical flood protection asset, the FloodFree Concealed Flood Barrier requires periodic inspection and maintenance to ensure reliable operation when needed.

Manufacturer recommendations include six-monthly inspections of the barrier assembly, with additional inspections following any flood event. Annual maintenance includes operational testing of the barrier, warning systems, seals, drainage components, and pump infrastructure, along with removal of accumulated debris and verification of system performance.

Following commissioning, the homeowner received quality assurance documentation, operation and maintenance guidance, warranty information, and recommendations for ongoing servicing.

Watersmart provides ongoing inspection, testing, servicing, and maintenance support to help ensure the system remains operational, reliable, and ready to deploy during future storm events. Maintaining the recommended servicing schedule is also important for preserving warranty coverage and ensuring long-term system performance.

The Results

The completed system now provides permanent flood protection for the basement carpark while preserving full driveway functionality and the visual appearance of the property.

Key outcomes include:

Automatic flood protection operating 24 hours a day

No reliance on external power or manual deployment

Reduced risk of future flood damage and associated repair costs

Continued unrestricted vehicle access during normal conditions

Fully concealed infrastructure that preserves the property's appearance

Durable marine-grade aluminium construction designed for long-term performance

Ongoing serviceability and asset management support through Watersmart

By combining passive operation with specialist engineering and commissioning, the system provides peace of mind that the property is protected even when occupants are away.

Why the Project Was Successful

The success of the project was driven by early technical involvement, strong collaboration between Watersmart and Frontline Projects, and careful integration of the flood barrier within the site's drainage and driveway infrastructure.

By combining specialist flood protection expertise with comprehensive commissioning, testing, and quality assurance processes, the project team delivered a solution that met both the performance and aesthetic requirements of the site.

The result is a discreet, fully automatic flood protection system that protects a vulnerable basement carpark from future stormwater ingress while maintaining the everyday functionality and appearance of the property.