Septic LPP Orifice Flow and Squirt Height

Per-orifice flow, total orifice count, and system flow for a low-pressure-pipe or mound distribution lateral via the orifice-discharge equation. Orifice size, spacing, and layout come from the permitted onsite design.

Run the calculator

Formula and source

Per-orifice flow (gpm) = 19.63 x Cd x d_in^2 x sqrt(h_ft) (Cd 0.6 gives the familiar 11.79 coefficient); system flow = per-orifice flow x orifices per lateral x laterals.

Standard orifice-discharge equation; university onsite-wastewater extension low-pressure-pipe design guidance, by name.

Audience

This tile is built for plumbers and the adjacent professions in the Plumbing and Gas group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

Related tiles

Posture

Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.