Building near pipes and drains

We maintain a network of pipes for sewer, stormwater and water to safeguard the community from disease and protect our environment and properties. When these pipes fail or require upgrading we require access to carry out the necessary work. Approval to build over pipes will not normally be given if the integrity of the system is compromised in any way.

Have a suitably qualified person prepare site and foundation plans of the building and accurately plot the pipes in relation to your building work. Our records should be treated as a guide only. If doubt exists, contact us as there are various methods available to locate the pipes. It is the property owner's responsibility is to ensure that these service pipes are not built over.

We generally require the structure to be located a minimum of the greater of the following two distances:

• 5m from the centre line of the pipe; or
• the depth of the pipe plus the diameter of the pipe plus 0.2 metres (e.g. 2m deep pipe, 150mm diameter requires distance of 2.0 + 0.15 + 0.2 = 2.35m) from the centre line of the pipe.

In exceptional circumstances we may allow buildings or additions to be built over or near pipes, In cases where approval is granted, costs to meet conditions must be met by the applicant and these can be significant.

If stormwater, water and/or wastewater pipes are under the ground where you want to build, you have three options:

• consider alternative locations within the property to site the building. This is the most desirable option because the pipes are not affected and there are no costs to you.
• divert the pipes around the building site. Diversion work must be completed before building work starts. Diversion is dependent on the alignments and grades of the existing pipe and is not always possible.
• as a last resort, you may be granted permission to build over the pipes, subject to a deed of covenant and a memorandum of encumbrance being registered against the property title. Permission to build over public pipes is granted only in exceptional cases and applications are assessed on a case-by-case basis. The applicant must meet all associated costs including the inspection of the condition of the pipe, and legal documents. Building may commence only when we are satisfied that there are sufficient safeguards in place to protect the pipes.

Ideally all pipe work should be within the road reserve, but this is not always possible. Under the Local Government Act, we have the right to have pipes on private property, and to maintain and protect them. Many pipes were installed within private property by the subdividers of the land and we inherited these pipes.

In New Plymouth District there are many kilometres of water, stormwater and wastewater pipes. Some of these pipes are within private property and although some are within registered easements, many older pipes are not but they are legally allowed to remain. We occasionally require access to these pipes for repair or replacement.