Convert Hectopascals to Feet of Water
Convert Hectopascals (hPa) to Feet of Water (ftH₂O) instantly and accurately.
Conversion Formula
ftH₂O = hPa × 0.03345525633
About Hectopascals
A hectopascal (hPa) = 100 Pa = 1 mbar - the WMO-official SI-compatible meteorological pressure unit since 1986, replacing millibar with no numerical change. All modern surface observations (METAR, SYNOP), digital barometers, aviation weather, and weather apps report in hPa. QNH altimeter settings outside North America are in hPa. ICAO standard sea-level pressure is 1013.25 hPa. Continental high-pressure record exceeds 1084 hPa; Typhoon Tip (1979) holds the low record at ~870 hPa. 1 hPa = 100 Pa.
About Feet of Water
One foot of water column (ftH₂O) ≈ 2,989 Pa - the US customary equivalent of cmH₂O used in civil and hydraulic engineering. Municipal water supply systems are designed for 40-80 psi head ≈ 92-184 ft; fire suppression sprinkler systems require minimum 7 psi ≈ 16 ft. Well pump specifications, sump pump head ratings, irrigation mainline pressure, and drainage calculations all use feet of head. 1 ft of water = 12 in WC = 0.4335 psi ≈ 2,989 Pa.
Quick Reference Table
| Hectopascals (hPa) | Feet of Water (ftH₂O) |
|---|---|
| 1 hPa | 0.0334553 ftH₂O |
| 2 hPa | 0.0669105 ftH₂O |
| 5 hPa | 0.167276 ftH₂O |
| 10 hPa | 0.334553 ftH₂O |
| 25 hPa | 0.836381 ftH₂O |
| 50 hPa | 1.67276 ftH₂O |
| 100 hPa | 3.34553 ftH₂O |