Think twice before you dig

Think twice before you dig - that's the message that Land Information New Zealand (LINZ) is sending to contractors to encourage them to keep an eye out for survey marks when working in the ground.

Survey marks are used for surveying of property boundaries, engineering, road building, mapping and resource management projects. They are most commonly seen on the roadside, but can be located anywhere on public or private land.

These small metal marks might not look valuable, but they're a vital part of New Zealand's infrastructure, says Deputy Chief Geodesist John Ritchie.

Their value is in their location, and it can costs thousands to repair or replace them if they're damaged or lost. This adds to the cost of construction and development, and undermines the work required to reinstate property boundaries.

John says that damaging or destroying a mark is also against the law, meaning that anyone who does so can be fined.

Thankfully there's an easy way to check that your work wont do this is a one-stop shop website for making sure its safe before doing anything that might disrupt infrastructure in the ground.

The website includes information on survey marks, power cables, water pipes and other underground infrastructure. It removes the need for contractors to contact the owners of this infrastructure individually, and gives advice on next steps if work is likely to cause damage.

If notified of work that is likely to disrupt a mark, LINZ will provide information on marks that require protection, John says.

In some cases it may be possible to re-design your work-site to avoid at-risk marks. If that's not an option, contractors will need to contact a licensed surveyor to carry out the required protection work.

Whatever the solution its easier and less costly if we know first. So please help us to protect this important infrastructure think twice, and visit

For more information on survey marks contact:

Land Information New Zealand:;

New Zealand Institute of Surveyors:

or a survey company in your area.

To access the beforeUdig service: