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First Flush Diverters

First-flush diverters are important to tank water quality.

When it rains, water slowly builds up in the roof guttering system before it enters the downpipe. At this time the water is saturated with all the ‘nasties’- dirt, pollens, bird droppings etc. To ensure the quality of water supply from a water tank, we want to prevent these ‘nasties’ from reaching the tank.

With a first-flush diverter fitted, as water enters the downpipe, it first flows into the diverter tube. As the water rises in the tube, so does a floating ball, until the ball seals off the tube. This seals the polluted water in the diverter tube. The rest of the roof water, minus most of the ‘nasties’, is then automatically diverted to the water tank.

When the rain stops, the diverter chamber empties itself through the control valve at around 1 LPH. so that the diverter tube is empty for the next time it rains.

If the roof guttering is not fitted with a mesh, or the outlet is not fitted with a screened rain head, the water diverter will fill with leaves and debris very quickly and will have to be emptied more frequently by unscrewing the end cap on the diverter chamber. Fitting a Leaf Eater Rain Head will solve this problem.

In some areas of Australia it is law that first flush devices be fitted when rainwater is captured and stored in tanks.

Enviro Friendly Products offers a range of four excellent First-Flush Water Diverter Kits. All you have to do is fit the kit to an appropriate length of pipe. Full instructions come with each kit.