PHONE: 09 813 0909


Before you put in a retention/detention tank it is important you know the difference. Both collect rainwater and storm water. A retention tank is to keep the water for use at a later date, whereas a detention tank eventually drains the water after it is collected.

Civil Underground has the expertise to advise you on the tank/s required, if any permits are required and if the tanks meet engineering requirements such as AS/NZ 2032-4 pipework or the Environment Protection Authority code of practice for hazardous substance tanks.

Working hand in hand with the client our experienced team will first evaluate your home’s environment and from there optimal recommendations will be made.

The installation process while on many occasions is not overly complex it is important that the tanks are correctly sited and on testing they meet all manufacturer’s requirements as to best practice operation.

The overview is that Civil Underground will ensure that the installations operate to peak performance and will result in cost savings. The water in the retention tanks can be used for watering gardens, cleaning cars and such like.

The site of the tanks is most important and Civil Underground will ensure the tanks are sited to ensure that as the water from the detention tanks will be correctly released into the ground at a rate that prevents flooding.

Civil Underground staff are focused and committed to health and safety and will be NZQA certified in matters such as confined space, working at heights, first aid. Civil Underground is fortunate to have a Health and Safety advisor with 15 NZQA certifications and is a qualified NZQA health and safety tutor.

We insist that we will not walk away from any site until you and Civil Underground are completely satisfied with the work done.



PHONE 09 813 0909

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