{
 "tool": "pipe-flow",
 "toolVersion": "1.0.0",
 "methods": [
  "pipe-flow 1.0.0",
  "manning-uniform 1.0.0"
 ],
 "commit": "ab22876",
 "date": "2026-11-04",
 "summary": "13 of 13 cases (47 values) within tolerance against EPANET 2.2, Hydraulic Toolbox 5.5.3.0, FHWA HEC-22 4th ed. (2024).",
 "note": "Generated by _workspace/tools/hh_verification.mjs from the fixtures; commit = code verified.",
 "cases": [
  {
   "id": "E1-1",
   "what": "12-in pipe flowing full, Hazen-Williams C 130, head loss over 1000 ft at 3.2144 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 2,
   "maxDiff": "0.06 %",
   "pass": true
  },
  {
   "id": "E1-2",
   "what": "18-in pipe flowing full, Hazen-Williams C 120, head loss over 1000 ft at 10 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 2,
   "maxDiff": "0.07 %",
   "pass": true
  },
  {
   "id": "E1-3",
   "what": "8-in pipe flowing full, Hazen-Williams C 100, head loss over 2500 ft at 1.5 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 2,
   "maxDiff": "0.04 %",
   "pass": true
  },
  {
   "id": "E1-4",
   "what": "18-in pipe flowing full, Darcy-Weisbach, roughness 0.0005 ft, minor loss K 1.5, head loss over 1000 ft at 10 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 2,
   "maxDiff": "0.08 %",
   "pass": true
  },
  {
   "id": "E1-5",
   "what": "6-in pipe flowing full, Darcy-Weisbach, roughness 0.00015 ft, head loss over 500 ft at 1 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 3,
   "maxDiff": "0.08 %",
   "pass": true
  },
  {
   "id": "E1-6",
   "what": "24-in pipe flowing full, Darcy-Weisbach, roughness 0.004 ft, head loss over 2000 ft at 20 cfs",
   "reference": "EPANET 2.2 (owner-run 2026-11-02)",
   "compared": 3,
   "maxDiff": "0.08 %",
   "pass": true
  },
  {
   "id": "TB-C4",
   "what": "Circular, normal depth",
   "reference": "Hydraulic Toolbox 5.5.3.0 (owner-run 2026-11-01)",
   "compared": 13,
   "maxDiff": "0.15 %",
   "pass": true
  },
  {
   "id": "TB-C5",
   "what": "Circular, normal depth (two-depth range, warning required)",
   "reference": "Hydraulic Toolbox 5.5.3.0 (owner-run 2026-11-01)",
   "compared": 13,
   "maxDiff": "0.09 %",
   "pass": true
  },
  {
   "id": "TB-C6",
   "what": "Circular, discharge above the largest open-channel flow (refusal)",
   "reference": "Hydraulic Toolbox 5.5.3.0 (owner-run 2026-11-01)",
   "compared": 1,
   "maxDiff": "both refuse",
   "pass": true
  },
  {
   "id": "HEC22-E9.1-RCP",
   "what": "Circular, discharge",
   "reference": "FHWA HEC-22 4th ed. (2024) (published example)",
   "compared": 2,
   "maxDiff": "0.85 %",
   "pass": true
  },
  {
   "id": "HEC22-E9.1-CMP",
   "what": "Circular, discharge",
   "reference": "FHWA HEC-22 4th ed. (2024) (published example)",
   "compared": 2,
   "maxDiff": "0.82 %",
   "pass": true
  },
  {
   "id": "HEC22-E9.1-D-RCP",
   "what": "Circular, diameter flowing full",
   "reference": "FHWA HEC-22 4th ed. (2024) (published example)",
   "compared": 1,
   "maxDiff": "0.17 %",
   "pass": true
  },
  {
   "id": "HEC22-E9.1-D-CMP",
   "what": "Circular, diameter flowing full",
   "reference": "FHWA HEC-22 4th ed. (2024) (published example)",
   "compared": 1,
   "maxDiff": "0.24 %",
   "pass": true
  }
 ]
}