Convert Feet of Water to Hectopascals
Convert Feet of Water (ftH₂O) to Hectopascals (hPa) instantly and accurately.
Conversion Formula
hPa = ftH₂O × 29.8906692
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.
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.
Quick Reference Table
| Feet of Water (ftH₂O) | Hectopascals (hPa) |
|---|---|
| 1 ftH₂O | 29.8907 hPa |
| 2 ftH₂O | 59.7813 hPa |
| 5 ftH₂O | 149.453 hPa |
| 10 ftH₂O | 298.907 hPa |
| 25 ftH₂O | 747.267 hPa |
| 50 ftH₂O | 1494.53 hPa |
| 100 ftH₂O | 2989.07 hPa |