Downspout First Flush Water Diverter Kits

Want cleaner cistern or rain barrel water?

Image logo First Flush Roof Wash Diverter - Rain Harvesting of Australia

First Flush Water Diverters improve water quality, reduce tank maintenance and protect pumps by minimizing the first flush of water, which may contain contaminants from the roof, from entering the tank.

Instead of flowing to the water tank, pollutants are diverted with the initial flow of water into the chamber of the water diverter. The first flush water diverters utilize a dependable ball and seat system - a simple automatic system that does not rely on mechanical parts or manual intervention. As the water level rises in the diverter chamber the ball floats, and once the chamber if full, the ball rests on a seat inside the diverter chamber preventing any further water entering the diverter. The subsequent flow of water is then automatically directed along the top of the "T" to the collection tank.

There is an additional filter supplied with this First Flush Diverter Kit. It sits inside of the standpipe. This mini filter helps keep the line open so that the water in the standpipe may drain out slowly through the bottom. Yes, the speed at which the water leaves the standpipe is adjustable with drip regulators. Attach a drip hose to the bottom fitting and use this water too.

This chamber and filter will need to be cleaned. Unscrew the bottom fitting and everything will fallout of the chamber, including the filter and plastic ball. Carefully clean everything, put the green ball back inside the standpipe and screw bottom fitting into place.

You will need to supply the 3, 4 or 12" diameter PVC standpipe; fittings from the downspout to the First Flush Diverter; drain hose for the bottom drain; fitting from the "T" of the First Flush Diverter to the to water containment unit.

Downspout First Flush Water Diverter Kits
How an Installed Downspout First Flush Device works
First Flush Rain Harvesting

Watch the general explanation video clip about First Flush Rain Harvesting Water Diverter Filter

Here is another great video with more detailed information

If you need to divert a large volume of water from entering the cistern, review the page for the larger 12" kit.

Planning a large underground cistern? You might consider this In-Ground First Flush Diverter.

Downspout First Flush Diverter KITS


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