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First Flush devices have been popular in rainwater systems in other country's for a number of years. They are practical, efficient and yet very simple. Our Rain Flush device doesn't require a lot of maintenance.  A simple cleaning of the collection chamber several times a year will normally suffice. Buying a commercially made first flush device can be an expensive addition to your system. While there are several good ones on the market that will do the job they are restrictive because of their cost and factory configured sizes.

Having seen the need for a product that is inexpensive, effective and doesn't have to travel half way around the world, we started to work on a design of our own version of a first flush. Our criteria was to make it as simple, inexpensive and versatile as possible, while making sure that it would last indefinitely. The product we have ended up with meets all of that criteria. Our Rain Flush Kit will allow you to use locally available components for the bulk of your system while we supply you with the few items that aren't so easy to find at your local hardware store. We'll get into that a little farther down the page. But first, let's take a look at how a First Flush device works.

While it's raining

The image on the right shows how a first flush device works to separate the first water that comes off out of the gutter when it starts to rain. The water pours in the 4" chamber. As the water rises, the ball floats up in the chamber until it seals the opening at the top. The opening in the top of the chamber is such that a 1" air gap is created between the dirtier water in the chamber and the cleaner water flowing by to the water storage area.  The larger your roof area is, the larger the collection chamber is. The one in the image is short for illustration purpose.

 When the rain stops

This image shows what happens once the rain stops. Once the water flow ceases, the ball sinks back down to rest on top of the elevated strainer pipe within the 4" chamber. Water is released from the chamber through the strainer pipe at a slow adjustable rate so that when it stops raining the ball will drop to the lower portion of the chamber ready to take in more of the dirty water. Once it starts raining again, the process starts over and the ball raises to the top after collecting the dirty water. The base of the chamber is open-able for cleaning.

This is a pretty simple process. When combined with several of the other passive filtration systems that we recommend for the D-I-Y Rainwater Harvester, you can have an inexpensive, low maintenance system in no time at all.

This is what we supply with this kit

• An NSF safe ball for a 4" system.

• A sturdy washer for a tight seal.

• A pressure rated internally threaded bulkhead.

• Adjustable Stand Pipe with Stainless Steel Strainer Screen.

• The kit comes with complete instructions and parts list  to build a 1st Flush Device.

ONLY $24.98