About us

Sources & Methodology

Where our facts come from, how we check them, and how our calculators and cost ranges are built.

Source hierarchy

How we weight sources
PrioritySourcesUsed for
HighestManufacturer manuals and specifications (currently Franklin Electric, Amtrol, Pentair and Grundfos); federal and state agencies (USGS, EPA, CDC, state health and water agencies)Settings, limits, procedures, safety warnings; public-health and ownership facts
HighIndustry organizations and trade publications (Water Systems Council, NGWA's Water Well Journal, The Driller); engineering standardsMethods (tank sizing, drawdown), practice guidance
SupportingEstablished cost and home-improvement publishers (for example HomeGuide, This Old House)Published cost ranges, always attributed and dated
Discovery onlyForums, videos, social media, other websitesFinding the questions people ask — never the sole source for a technical or safety claim

How we verify

  1. We read the source itself — the PDF manual, the agency page — not a summary of it.
  2. We record the date we checked it and the specific facts we used.
  3. If we can't open a source directly (for example, a page blocked in our region), we don't cite it.
  4. Where manufacturers differ, the guide says whose instructions it follows and tells you to follow your own equipment's manual.

Calculations

Our calculators use published methods and basic physics, and each tool page shows its formula: precharge rules from Amtrol, Pentair, Franklin Electric and Grundfos; tank drawdown from Boyle's law as presented in The Driller; minimum run times from Water Well Journal; the 2.31 feet-per-psi conversion used in manufacturer literature; and the U.S. Standard Atmosphere for elevation. Tables marked as "our calculation" apply those same published formulas. When there's no sourced method for something, we don't make one up.

Cost data

Cost ranges are national figures published by cost-guide companies. We show who published each range and when, use one publisher consistently within a calculation, and never present a published range as our own survey or as a quote.

Documents we currently rely on

Manufacturer

Industry organization

Trade publication (NGWA)

Trade publication

Government

Cost publisher

Search documentation

Ad platform documentation