Roughness and Hazen Williams Coefficients for various pipe materials (carrying water):
One of the values of using the Hazen Williams Equation is that the value C, does not depend on Reynolds Number.
Below you will find a table of various Hazen William Coefficients: grouped by pipe type:
| Table 1: Hazen Williams Constants | |||
| C | |||
| type of pipe or surface material: | range | clean | design |
| mineral | |||
| concrete | 152-85 | 120 | 100 |
| cement-asbestos | 160-140 | 150 | 140 |
| vitrified clays | 110 | ||
| brick sewer | 100 | ||
| iron | |||
| cast, plain | 150-80 | 130 | 100 |
| cast (10 years old) | 113-107 | ||
| cast (20 years old) | 100-89 | ||
| cast (30 years old) | 90-75 | ||
| cast (40 years old) | 83-64 | ||
| cast, tar (asphalt) coated | 145-50 | 130 | 100 |
| cast, cement lined | 150 | 140 | |
| cast, bituminous lined | 160-130 | 148 | 140 |
| cast, centrifugally spun | |||
| Ductile Iron Pipe (DIP) | 140 | ||
| galvanized, plain | |||
| wrought, plain | 150-80 | 130 | 100 |
| steel | |||
| welded and seamless | 150-80 | 140 | 100 |
| interior riveted, no projecting rivets | 139 | 100 | |
| projecting girth rivets | 130 | 100 | |
| projecting girth and horizontal rivets | 115 | 100 | |
| vitrified, spiral-riveted, flow with lap | 110 | 100 | |
| vitrified, spiral-riveted, flow against lap | 100 | 90 | |
| corrugated | 60 | 60 | |
| miscellaneous | |||
| copper and brass | 150-120 | 140 | 130 |
| wood stave | 145-110 | 120 | 110 |
| transite | |||
| lead, tin, glass | 150-120 | 140 | 130 |
| plastic (PVC and ABS) | 150-120 | 150-140 | 130 |
| fiberglass | 160-150 | 150 | 150 |
| wooden or masonry pipe (smooth) | 120 | ||
Note: C values for sludge are 20-40% less than the corresponding water pipe values.