A property drainage plan records what a council or water authority holds about the drainage serving a particular property. Depending on the authority and the age of the building, records may include private wastewater pipes, stormwater drains, connection layouts or as-built and as-laid drawings. In many cases the drawing sits inside a wider property file rather than existing as a standalone plan, and not every property has one. Drainage Plans NZ helps you identify and request the recorded drainage information held for your address.
What a recorded drainage plan may show
Depending on the authority and the records retained, a drainage drawing may show the layout of private wastewater pipes, stormwater drains, gully traps, inspection points and the point where private drains connect to the public network. Some drawings are as-built or as-laid records prepared when the drainage was constructed; others are simpler sketches attached to a historic permit or building consent. A drawing may be included within a property file rather than supplied as a standalone plan.
As-built, as-laid and historic drainage drawings
You will see several terms used across New Zealand councils. An as-built or as-laid drainage plan records drainage as it was actually constructed, which can differ from the approved design. Older properties may only have a drainage sketch from the original building permit. Whatever the format, these records describe what was documented at the time — they are not a current survey of the pipes in the ground.
Who requests property drainage records
Homeowners request drainage records before renovations, extensions or landscaping that could affect buried pipes. Plumbers and drainlayers use them to trace private lines when investigating blockages or planning new connections. Builders and developers check them before earthworks, and property buyers use them as part of pre-purchase due diligence — always subject to the accuracy and completeness of what was recorded.
Drainage plan vs wastewater network map
A private drainage drawing concerns recorded drainage at a specific site. A wastewater network map principally identifies public utility assets such as mains and manholes; it is not automatically a record of all private pipes. If you need the public network picture instead, see our wastewater network plans and stormwater network plans pages.
How to request a plan through Drainage Plans NZ
Search and select your property address using the address search on this page. We identify the relevant council or water authority from the property location and show you the available request categories with pricing before you confirm. Record availability must be verified for the individual property — we never promise that a document exists until the authority's records have been checked.
Why a council may hold no plan
Record holdings vary by authority and property age. Drainage laid before modern consent processes may never have been drawn, some records remain on paper and were never digitised, and some drawings have been lost or were never submitted. Not every property has a retained drainage drawing, and a property file may contain only limited information.
Important limitations
Do not rely on recorded plans to excavate. Pipes may have been altered, extended or replaced since the drawing was made, and recorded positions are not guaranteed to be accurate. Obtain appropriate utility locating and professional advice before any work begins, and follow before-you-dig procedures.
Drainage Plans NZ is an independent third-party document sourcing service, not a council or utility. Records vary and availability must be verified for each property. Plans and network maps are not a substitute for on-site locating or before-you-dig procedures.