Back in 2018, Whangārei Airport had a problem — its aging runway was starting to unravel like a well-worn jersey, thanks to heavy oxidation. A full asphalt resurface? That was way out of the budget. EnviroShield offered a potentially faster, more cost-effective alternative to conventional resurfacing — delivering long-lasting protection without the hefty price tag
EnviroShield is a high-performance surface treatment designed to extend the life of aging asphalt and chip seal surfaces that are beginning to fret. Applied warm via spraying, it creates a durable protective layer that slows deterioration and enhances surface integrity.
With its low viscosity, EnviroShield penetrates deep into the surface, curing to form a waterproof barrier that locks in aggregate and reduces oxidation.
The formulation features an ultra-hard, abrasion-resistant bitumen, engineered to withstand the stresses of heavy use while maintaining a low-tack finish.
In Whangarei that meant extending the life of the runway by improving its watertightness and slowing oxidation. Comprehensive reviews were conducted in year two and year six.
Two years in, the results confirmed EnviroShield’s effectiveness in protecting the runway from oxidation, with a noticeable contrast between treated and untreated areas. The treatment had successfully locked in aggregate, preventing loose chip and unravelling.
After six years, the surface showed signs oxidation levels had returned to pre-treatment conditions, signalling that the initial EnviroShield application was nearing the end of its lifespan.
While no unravelling was evident, it was likely to develop within the next year based on the observed oxidation rate.
Cracks had started to appear along some paver joins, highlighting the need for prompt crack sealing to prevent water related damage.
Skid resistance testing confirmed the surface remained above the minimum maintenance level, posing no immediate slip risk when wet.
The conclusions drawn from the reviews vindicated the claims. The application of EnviroShield had successfully extended the life of the runway with hefty cost savings and no added danger to users — and the surface was still was up for a new application and seven more years.
In the most recent re application, the team applied EnviroShield during the night shift, alongside successful completion of line marking, all before the first aircraft movement the following morning.
