MIL-HDBK-1005/7A
4.7.6.1
Pressure. Provide pipe and fittings of a class
suitable for the operating pressure, plus an allowance, based on
detailed analysis, for water hammer. Assume a fouling factor in
pipeline friction based on local experience. Where local data
are unavailable, use a friction factor of n = 0.017 or Hazen -
Williams coefficient of c = 100.
4.7.6.2
Materials . Materials for water mains should be
selected from the following:
a) AWWA C104/A21.4, ANSI Standard for Cement-Mortar
Lining for Ductile Iron Polyethylene Encasement for Ductile Iron
Pipe Systems . AWWA C110/A21.10, ANSI Standard for Ductile Iron
and Gray-Iron Fittings, 3 in through 48 in, for Water and Other
Liquids .
b) AWWA C950, Glass-Fiber-Reinforced Thermosetting
Resin-Pressure Pipe.
c) AWWA C900, Polyvinyl Chloride (PVC) Pressure Pipe
4 in. through 12 in., for Water, and 40 CFR Part 141.50.
1) AWWA C906, Polyethylene Pressure Pipe and Fittings
4 in. through 63 in.
Materials for exposed pipes under piers should be
either flanged ductile iron or cement mortar lined, steel pipe;
AWWA C205, Cement -Mortar Protective Lining and Coating for Steel
Water Pipe--4 in. and Larger--Shop Applied. Steel pipe is
preferable where insulation is required. Pipe shall have a 250
psi rating and be properly coated for corrosion protection.
4.7.6.3
Valves. Use butterfly valves having a 250psi rating
constructed of materials resistant to corrosion by the source
water. Refer to AWWA M44, Distribution Valves: Selection,
Installation, Field Testing and Maintenance.
4.7.6.4
Construction . Check loads at joints, bends, fittings,
valves and other necessary locations, and provide necessary
tie-downs and blocking.
a) Location. Where pipes run under or inside of
structures, provide access manholes in the structures.
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