About SepticCompass

SepticCompass is a free set of calculators for the questions septic-system owners and home buyers actually ask: what will it cost, what size do I need, and how often must I pump it.

Most septic information online is either a contractor's sales page or a thin paragraph that gets summarized away. We took a different approach: each tool is built on published, citable engineering — the EPA Onsite Wastewater Treatment Systems Manual (around 150 gallons per bedroom per day, 48-hour retention), the standard percolation-to-loading-rate formula, IPSDC-aligned code minimums, and the Penn State / Ohio State Extension pumping-frequency tables. We show the formula and the assumptions on every page, so you can see exactly how the number was derived.

The goal is a fair, independent baseline. Contractors sometimes oversize systems or quote a wide range; knowing the underlying standard lets you ask better questions and recognize a reasonable quote.

SepticCompass is part of the Compass family of practical homeowner calculators. The cost coefficients and state data are version-controlled and dated, and we refresh them periodically.

Questions or corrections? Email hi@septic-compass.com.