Can I build over the septic tank or land application area?
We advise that you do not build over your septic tank as you need to have readily available access to the tank for inspection and maintenance purposes. The structural integrity of a building can also be compromised if sited too closely to a septic tank.
You cannot build over your land application area. A key to the successful function of land application areas is the evaporation of moisture from soil to the atmosphere. If you build over the land application area you reduce the amount of solar exposure and airflow which reduce evaporation. Potentially leaving you with an overloaded and failing system.
As this is a matter of property title you will need to enquire with the Statutory Planning department to request an alteration. Wastewater envelopes are sited based on the information gathered during a land capability assessment to make sure wastewater can be retained within the property. It may not be possible to relocate the wastewater envelope.
Once Statutory Planning receives the application it will be forwarded to the Public Health Department for consideration.
The Public Health Department will consider if the request conforms with domestic wastewater regulatory requirements. Ie. will the proposal retain all wastewater onsite while meeting setback and environmental conditions?
In addition to required building permits, you must submit an application to the Public Health Department if altering a building connected to your septic system. This is because the alteration may increase the load on the system and cause it to fail.
Some tell-tale signs include:
- A smell associated with the septic tank or effluent application area, often like rotten eggs.
- The ground around the effluent application area is soggy or is pooling water.
- There is lots of green grass on or around the effluent application area. There is a line of dense green grass trailing downhill from the application area.
- The toilet or sink drains are slow to clear, make gurgling noises when draining or keep backing up.
Why can’t I just have a septic tank and aggy trenches?
This system produces effluent to a primary standard. There are many circumstances where secondary treatment standard is required, some of these are:
- Small land area that restricts the size of the effluent application area.
- A concentration of septic systems within close proximity, ie. subdivision.
- Close proximity to a waterway.
- The soil on your property will not be able to cope with effluent of this standard.