Retention & Detention Tanks

Detention and retention tanks are large underground or above-ground containers designed to manage stormwater on a wide range of New Zealand sites.

Both tank types help control the flow and quality of stormwater. Detention tanks reduce peak flows and help prevent downstream flooding, while retention tanks provide a sustainable water source for non-potable uses. These systems are commonly found at commercial developments, residential subdivisions, schools, and industrial sites.

Regular maintenance is essential to ensure optimal performance, prevent blockages, and extend the lifespan of your tank system. Over time, sediment, debris, and organic matter can accumulate, reducing storage capacity and increasing the risk of flooding or system failure.

At Dutton Stormwater, we provide professional tank maintenance services across New Zealand to keep your stormwater management system efficient and compliant. Our fleet of compact, high-performance vacuum trucks is built to tackle any stormwater tank, big or small, while easily navigating hard-to-reach sites. For underground tanks, maintenance may require confined space entry, which is performed by our specially trained technicians following strict safety protocols. No matter the challenge, we deliver where you need it most.

Detention tanks typically require maintenance annually, but this can vary depending on your site and system usage. During each service, we assess your tank’s condition and provide a tailored maintenance recommendation in your service report. With our nationwide team and advanced reporting platform, we make stormwater maintenance simple, reliable, and transparent.