Irrigation

IRRIGATION (Reticulation)

Perhaps the most important aspect of your Greywater system is the Irrigation. Part of our Services is to supply, design and install Greywater Dripline.

Greywater is dispersed via Dripline. The reason for dripline is to avoid run-off and human contact of the water, reduce evaporation and plant disease, deliver the water directly to the root zone, and eliminate wind drift and “over-spray”. The same benefits of dripline are also there for Mains water or Bore water Irrigation (no staining to walls and fences also).

DRIPLINE

Greywater dripline is defined by its Lilac colour. It has a high flow rate, generally each emitter will distribute in the range of 6-9 litres per hour. These emitters are spaced at 300 mm intervals along the dripline and the dripline is in the range of 13-17 mm in diameter. Each emitter has a large internal filter to stop it clogging. Periodic flushing of the dripline is required to keep it clean. Depending on the plant varieties and soil types will determine how far we space the driplines from each other. Light sandy soils will drain the greywater away quickly compared to compacted heavy soils (loams and clay). The lighter the soil the closer the driplines should be. Plants with a high water requirement should have driplines spaced closer together than those with a lower water requirement. Consideration should be given to the extent of the root system – large canopies will generally have a large root system so don’t just simply dripline around the trunk.

INSTALLATION

Dripline Irrigation can be installed to your garden in many different ways. We generally transfer the greywater in 25 mm Lilac LDPE (Low Density Polyethylene) from the pump to the garden beds or lawn areas. In garden beds the dripline is placed on top of the soil and then mulched over. The mulching reduces evaporation and hides the dripline in the garden bed. For sub-surface, or irrigating lawn areas, we position the dripline in the soil approximately 100 mm below the finished grass level. For “under lawn” applications it is really only possible when putting in new lawns. We then wrap the dripline in geotextile. This prevents the possibility of the grass roots wanting to grow into the emitters and stops the chances of the emitters sucking soil into the filters as water drains from the dripline. Setting up Greywater Irrigation is different to Mains or Bore water dripline irrigation as we are dealing with different pump pressures, variable pump out volumes and ‘Grey’ water which will have some contaminants in it. The dripline can either be set up in grid lines for mass plantings or coiled around individual plants. As with all dripline reticulation systems we need to have vacuum points and flush points.

We recommend the AWWS Greyflow Greywater Products

• AWWS is a Perth based company with systems researched and developed for Australian conditions.
• AWWS systems have won a range of awards and are sold Worldwide.
• AWWS has an unsurpassed warranty and backup service.

Mark Harland & Water Capture have been a Member of GWIG (Greywater & Wastewater Industry Group) since inception.

Mark Harland is the Treasurer at GWIG.