Detention Tanks

Drain Ninjas are experts at unblocking and clearing detention tanks, getting your stormwater drainage working again in a matter of hours. We handle emergency callouts 24/7 throughout Auckland, and can arrange periodic maintenance to prevent future problems. Give us a call today on 0800 4 NINJA

Excellent work and very friendly.


Very little to say; arrived on time, friendly couple, efficient, and quickly solved the problem for me. Had to use the hydro jet on the problem, and the bill when it came was much less than my plumber had estimated it would be.


I never leave reviews, but troy was well above expectations in his knowledge, experience and approach that i felt compelled to.


Finally a tradesman who is fabulous. I called. Troy actually came as planned. It was clear from the first interaction that he was genuine and knew what from what not. Troy identified the problem within seconds – believe that !! He tested. He checked GIS. The broken swer pipe, while on my property, is not mine to fix. Troy said he would not charge me for coming to id the problem. I only hope the outfit the neighbour gets to fix the broken sewer line is Troy’s company. Troy even said he was… available up to 7pm if I wanted to talk about it after talking to the neighbour. So refreshing to meet Troy who prided himself in telling me he owns the company.


Lifesavers, 100% recommend, make these guys your first call if you have a blockage – I wish we had. eW called for a second opinion. Fixed the problem super quick with friendly service.


The service I receive from Drain Ninjas has always been awesome, efficient and prompt..I highly recommend them.
Thanks guys for a great service, reasonable prices and awesome communication.



Detention tanks collect stormwater from a property before releasing it into the public system, helping to prevent problems for downstream drains and waterways. In Auckland, where council drainage systems are behind the growing number of houses, detention tanks are often a requirement for newer properties and are becoming increasingly common.

The Issue

Like other stormwater drainage systems, detention tanks will filter out natural debris such as leaves and silt, but these build up, particularly in areas with high amounts of foliage. If a detention tank hasn’t been cleaned in several years, its outlet will eventually block. The next time there is rain, water will flow back out of pipes and cesspits, eventually causing flooding on the property.

How We Fix The Problem

Drain Ninjas can easily fix a blocked detention tank by giving your detention tank a clearing and a clean with one of our vacuum trucks. Once the tank is cleared we will check the outlet line and confirm that the tank is in working order again. We also use the buildup of debris to advise on when your detention tank should next be cleared – generally, this is around once every 5 years.

Drain Ninjas are available for emergency callouts, but in general, we’d recommend having your detention tank cleared and checked before it starts to show signs of blockage, and during a period of low rainfall. Dried leaves and foliage are lighter and therefore cheaper to remove than when they are soaked and accompanied by large volumes of water. Where possible, arranging a detention tank clean in advance avoids possible flooding problems and costs less than an emergency clean.

Need Help With Detention Tanks?

Enquire Now Call Us
0800 475 008

The Drain Ninja recommendation of the month:

We recommend a septic tank service after a pump out to ensure the system works as per council requirements.


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