UFC 4-150-02
12 May 2003
2-4
PROTECTION
2-4.1
Protection of Mains and Laterals. Mains and laterals serving utility
connections must be protected from damage by waves, wind, floating debris or ice, and
tidal immersion. Where these lines could be subjected to such damage, they must be
placed in the utility corridor of a double deck pier, place in the trenches or tunnels of a
single deck pier, or special construction techniques must be used to provide a barrier.
Electrical conduits may be embedded in new concrete structures. It is preferable to
place electrical duct banks, manholes, and pull boxes such that they are cast integrally
with the pier deck and at least 0.6 m (2 ft) above the mean high water level. There are
cases where conduit and piping mains and laterals (except for POL systems) may be
hung exposed from the bottom of pier decks in protected locations. This is not a
preferred situation and is discouraged. In such cases, it is necessary to coordinate with
the structural design to secure inspection ladders and deck inserts, and to facilitate
installation of access platforms for maintenance purposes. New mains placed on
existing piers may be placed on top of the pier deck if other construction techniques are
impractical and if approved by the cognizant NAVFAC EFD/EFA OR USACE
DISTRICT. However, the use of utility trenches is highly preferred. Trench covers may
be concrete, steel plate, grating, or a combination of these, and as dictated by structural
loading, maintenance, and cost considerations. Coordinate design with structural
requirements. Note that permanently fixed covers (concrete and steel) create confined
workspaces. This is a significant operational problem (regarding inspection and
maintenance) that is generally undesirable and should be avoided if possible.
Identifiable markings should be located on the trench entrances. Corrosion protection
requirements are defined in the following paragraphs. Requirements for POL systems
are defined in paragraph 3-5 and refer to MIL-HDBK-1022A, Petroleum Fuel Facilities.
2-4.1.1
Above-deck Lines. At most types of berthing facilities, clear deck space
is at a premium, rendering above-deck mounting of utility services inappropriate,
operationally difficult, and generally unacceptable. A notable exception to this general
rule applies to dedicated fueling facilities. In these cases, above-deck mounting of fuel
lines is often the most functional solution because it allows for the proper and safe
access and maintenance of the fuel lines. See MIL-HDBK-1022A for additional
information and criteria.
2-4.1.2
Under-deck Lines. Except as noted above, utility service pipelines
should be not be located on the operating deck. At single deck piers, utilities should be
contained in trench structures, shielding the enclosed pipes from exposure to saltwater
and spray. Utility trench covers are of three basic types: solid, solid with personnel
access, and open gratings. Solid covers are generally used over most of the trench
length. Solid covers with 760 mm (30 in) diameter manhole covers should be located
over those portions of utility trenches containing valves, expansion mechanisms, or
branch connections which require easy access for inspection, maintenance, and repair.
Gratings may be substituted for solid trench covers with personnel access wherever
ready visibility of the respective utilities is required, or where ventilation of trench is
advisable (steam line drip assemblies). Unless specifically curbed against vehicular
traffic, covers must be designed for the same uniform loads and wheel loads as the
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