First Flush Delta In-Ground

Standard large format First Flush Diverters require you to use large diameter pipe (eg, 300mm / 12"). It can be difficult to source in smaller lengths and can be expensive.

The Delta's unique manifold design uses lengths of 100mm or 4" pipe instead, so sourcing the pipe to make the chamber is easier. It means you can assemble your First Flush Diverter quicker, to get the job done.

Each 1 meter of length in the Delta = 73 L diversion.
Each 1 yard of length in the Delta = 17.5 gal diversion.

By setting the regularity of your first flush diversion, you can optimise how often your First Flush Diverter drains.

Do you want the best quality water possible? Set it to a regular reset interval of three days or less.

Do you need to maximise the volume of water your capture? Increase the reset interval to two weeks or more.

Want to start off with a great compromise of water quality and quantity? Try five days.

This First Flush Delta In-Ground comes with most fittings you need to set the system up. Just your own T-piece according to your setup and add the pipe to create the storage chamber.

In-Ground diverters periodically drain the water-filled pipes in your “wet” rain harvesting system to prevent anaerobic fermentation and stop fermented water contaminating the rainwater in your tank. This drained water can then be released or used to water your garden.

Traditional First Flush Diverter valves have a tendency to clog over time - they only have a tiny hole so it is inevitable. The release valve on the Delta First Flush includes a unique funnel design and a much larger draining hole, which means that water drains as it's supposed to and there is far less chance of the unit becoming clogged.