Greywater central  | Greywater how-to books & videoCommon greywater mistakes  | Greywater policy center | Grey water Q&A

Flow Splitters (aka ABS double ell, twin elbow, twin 90°) for Branched Drain Greywater Systems

Special plumbing fittings which reliably split a gravity flow of unfiltered greywater into two streams, for use in Branched drain greywater systems, customized with access for inspection and cleaning.

$24 — Flow splitter, 2"
$19 — Flow splitter, 1.5"


Branched drain greywater systems provide reliable, economical sanitary, low maintenance distribution of household greywater to downhill plants without filtration or pumping.

The key component is the flow splitter. These flow splitters are ABS plastic double ells which we have drilled, tapped fitted with an inspection/ cleanout plug.

Complete design and installation instructions for flows splitters are found in our  Create an Oasis with Greywater-book

Typically, systems use at most one 2" flow splitter for the first split, after which the pipe is reduced down to 1.5" (for better flow, less plastic, easier geometry, and better economy). A system may use up to fourteen 1.5" flow splitters. This will split the flow in sixteenths, which is the maximum without the addition of a "dipper" distribution box to add surges to the flow (described in the book).

Note: Sorry we can't offer a better price on these--our costs just go up and up and our margins on them are quite low.

$24 — Flow splitter, 2"
$19 — Flow splitter, 1.5"

See also: