Site Analysis

Understanding all the features of a site, using and protecting the best, and minimising the impact of the worst.

Services and infrastructure

Before any design or construction work can begin, the services available on the site must be determined.

  • Services to urban sites will typically include sewer and stormwater drainage, mains water supply, power, gas and telecommunications services.
  • Rural sites will generally have power and telecommunications services, but may not have a mains water supply, gas, sewerage or stormwater services.
  • Remote sites may have no economical access to any services.

On this page:

  • options for services
  • health effects from electromagnetic radiation
  • underground network utility services
  • legal site issues
  • locating information.

Options for services

When assessing a site for building, the source of services must be determined.

Service Possible sources/options
Potable water supply Mains supply
A spring
A stream
A combination of sources if one source is unlikely to be sufficient for the expected demand
Electricity Mains supply
On-site generation, which may be one or more of:
• photo-voltaic
• wind generation
• micro hydro generation
• fossil fuel generator
Gas Reticulated
Sewage disposal Mains sewer – if a sewer main connection is available, the wastewater system must be connected to it
On-site wastewater treatment system
Stormwater disposal Stormwater drainage system
On-site disposal to an existing waterway, a storage tank (rainwater) or a soak pit
Telecommunications (telephone and internet) Landline connection
Cellphone connection

Health effects from electromagnetic radiation

Some people are concerned about living close to mobile phone towers and similar facilities. Considerable research has been done but not established a clear health risk.

The American Cancer Society has said “At ground level near typical cellular base stations, the amount of RF [radiofrequency] energy is thousands of times less than the limits for safe exposure set by the US Federal Communication Commission (FCC) and other regulatory authorities.”

The World Health Organisation has said: “there is no convincing scientific evidence that the weak RF signals from base stations and wireless networks cause adverse health effects.”

The biggest practical impact from building a house close to a mobile phone tower maybe the home’s reduced attractiveness for potential buyers when the owners want to sell.

Underground network utility services

In some generally urban locations, a site may be crossed by underground services such as water, gas, stormwater and sewer lines. These are likely to impose limitations on the design such as where the building may be built on the site and how close the building may be to the services.

Verify actual locations and invert levels of buried services. Do not rely on local authority drawings as they may not be accurate.

Legal site issues

Before beginning design work for a building, check the certificate of title for limitations from easements, covenants or restrictions on the site. A right of way should be registered on the title.

Locating information

Information regarding the infrastructure services and main utility service locations of a site are available on the property information memorandum (PIM) or land information memorandum (LIM). Local authority records such as building consent application documents and Code Compliance Certificates may provide additional information.

Gas and power and telecommunications companies should have information about the location of underground services.

Another service offering information on the location of underground utilities is Some utility companies refer people to this site.


Updated: 29 August 2017