Building consents for private sewage pumping stations

Set out below are the general requirements for two types of pumping systems, ie storage type pumping systems in ground and dry mounted pump systems above ground. The following information must be supplied with your building consent application if you require these types of systems:

Storage type pumping systems in ground

• Two copies of the manufacturer’s installation instructions along with two copies of site and drainage plans of the proposed layout will be required with the building consent application.
• The volume of storage shall be a minimum of 1m³ (220 gallons) for each unit served above the alarm float. This allows one days emergency storage.
• Engineering calculations, pump duty criteria and long section plans are required for each application for consent. For a single unit installation, one macerator or two standard pumps is acceptable.
• Two submersible macerator pumps are required for stations serving more than one unit. The levels of the pump station and the sewer to which it is to be pumped, and manufacturer’s pump specification brochures and curves are required with the application clearly showing all pipe sizes.
• Each installation shall have overflow (blockage) relief to prevent surcharge to within the building. The overflow relief point shall be strategically sited to ensure that any discharge does not create a nuisance and the discharge point shall remain visible and accessible.
• An approved alarm shall be fitted (a red light located in the kitchen is an approved alarm). The alarm is to turn on when the pump chamber level exceeds 25mm over the pump cut in level.
• Alarm lights are to show in at least two units where multiple units are served.
• The chamber housing the pump/pumps must have a sealed lid to prevent the ingress of surface water and be vented to atmosphere to comply with the NZ Building Code.
• A solenoid valve isolating all fixtures discharging to the system is to be fitted to activate in the case of power failure or blockage.
• A formal contract is required between all parties, and this agreement is to be registered on the title of the property where multi-unit development occurs. Pump discharge is to be via an access chamber prior to connection to council’s sewer line to provide access for cleansing and maintenance.

Dry mounted pump systems above ground

• Two copies of the manufacturer’s installation instructions and a site and drainage plan of the proposed layout will be required with the building consent application.
• Where dry mounted pump systems are installed, a solenoid valve is to be fitted to the incoming water supply main to interrupt the water supply in the event of a fault or high level condition in the unit or power failure.
• An approved alarm shall be fitted. (A red light located in the kitchen is an approved alarm). The alarm is to be activated when the above conditions prevail.
• Toilets and hand basins that discharge into a small tank with an installed pump (ie saniflo, sanitop, sanipaks or similar) will only be permitted where there are alternative wc and basin facilities within the same house on gravity connections.