BluenGrey specalises in wastewater plumbing for absorption trenches, evapotranspiration beds and effluent irrigation.
Why do I need a wastewater disposal area?
If you have an aerated wastewater treatment system (AWTS) or a septic tank, the wastewater will need to be disposed of onto a designated area of your property.
This area is often called a 'disposal area' and it is usually specified in the Geotechnical Report for your property. If you don't have a Geotechnical Report, also known as an On Site Wastewater Management Report, get in touch with us and we can help you arrange one.
Learn more about Geotechnical Reports in our New Systems FAQ.
What are the types of effluent disposal methods?
There are several options for how wastewater is irrigated or disposed of on your property; which is most suitable will be based on your Geotechnical Report. If your effluent irrigation or absorption trenches are failing or need to be improved or installed, we can help. With our experience in wastewater, we can ensure that your wastewater is managed safely and efficiently on your property.
Absorption trenches
A shallow, underground trench that can vary in design, width and length depending on the type of soil and the size of your house. Wastewater flows downhill from the septic tank to the trench. A collection well with a pump can be installed if the trench location is higher than the septic tank.
- Common disposal method for septic tanks and AWTSs.
- Sites with limited space available for effluent disposal.
- Good for free draining sub soils.
Typical absorption trenches are 600mm or 1200mm wide and up to 15m in length.
Evapotranspiration beds
Used when soil conditions are less suitable for absorption trenches and there is limited space. Typically, they are a rectangle area of ground that is excavated up to 600mm deep, filled with gravel and plumbed to disperse the water evenly. The top soil is moulded over the top of the bed and planted with grass and other plants.
- Common disposal method for septic tanks and AWTSs.
- Sites that prevent use of irrigation due to lack of space.
- Sites that prevent the use of absorption trenches due to clay soils.
- Good for small sites.
Typically they are a rectangle area no more than 4m wide and 20m long of ground that is excavated, filled with gravel and plumbed to disperse the water evenly. The top soil is moulded over the top of the bed and grass and other plants are used to encourage vegetation growth in this area.
Sub surface effluent irrigation
Effluent grade poly pipe buried underground, with evenly spaced drip emitters which allow a pre determined amount of wastewater into the soil across a wide area.
- Common disposal method for AWTSs.
- Property owners wanting the wastewater underground so that they do not have to see it or have exposure or contact with wastewater.
- Soil types that benefit from shallow irrigation and steep blocks.
- No damage to sprinklers or mowers, vehicles, tractors or animals.
Surface spray irrigation
Surface spray irrigation can be simply a line of above ground purple pipe and sprays.
- Common disposal method for AWTSs.
- Sites that have ground slope less than 20 degrees.
- Properties that have rocky ground (unable to bury poly pipe underground).
- Properties that have a larger area for above ground surface sprays.
- Soil types that benefit from surface spray.
Resources & FAQ
Useful guides and Council information, and answers to the most common questions we get asked about AWTS and septic tank systems.
Need a specialist in wastewater plumbing for your absorption trenches, evapotranspiration beds or effluent irrigation?
Get in touch with our friendly and knowledgeable team to organise an on-site inspection today.