WikiEngineer :: Water-Resources :: Hazen Williams Roughness Coefficient

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^[1]
	C
type of pipe or surface material:	range	clean	design

mineral
concrete	85-152	120	100
cement-asbestos	140-160	150	140
vitrified clays	100-140		110
brick sewer			100

iron
cast, plain	80-150	130	100
cast iron, old, unlined	40-120
cast (10 years old)			107-113
cast (20 years old)			89-100
cast (30 years old)			75-90
cast (40 years old)			64-83
cast, tar (asphalt) coated	50-145	130	100
cast, cement lined	130-150	150	140
cast, bituminous lined	130-160	148	140
cast, mitumastic	140-150
cast, sea-coated			100
Ductile Iron Pipe (DIP)			140
Ductile Iron, cement lined			120
galvanized, plain			120
wrought, plain	80-150	130	100

steel
welded and seamless	80-150	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
concrete lined steel forms			140
coal-tar enamel lined	150-154
miscellaneous
copper and brass	120-150	140	130
wood stave	110-145	120	110
transite
lead, tin, glass	150-120	140	130
Polyethalene (PE and PEH)			140
plastic (PVC and ABS)	120-150	140-150	130
fiber			140
fiberglass	150-160	150	150
fire hose			135
wooden or masonry pipe (smooth)			120
concrete lined wooden forms			120

Note: C values for sludge are 20-40% less than the corresponding water pipe values.

G. Williams & A. Hazen; "Hydraulic Tables, The elements of gagings and the friction of water flowing in pipes, aqueducts, sewers, etc.", 1914 - (Public Domain Version Available) or (via Google Books)