UFC 4-150-02
12 May 2003
3-8.7.4
Super Shore Power. SCDB lists "super shore power" requirements for
nuclear submarines. Super power is required for the ship's testing, checkout, and
refueling operations. These super shore power requirements are in addition to the
normal power requirements. Provide super power from a separate substation that
supplies no other loads. Portable substations connected to temporary service outlets
are recommended for this service. Extend primary service and provide connections for
these portable substations. The special requirements for submarine piers given in
subparagraphs 3-8.7.1, 3-8.7.2, and 3-8.7.3 above do not apply to super shore power.
3-8.8
Ground System. Provide a ground system at piers, wharves, quaywalls,
and other waterfront structures that measures not more than 5 ohms for all permanent
electrical equipment. Ground systems should be in accordance with NFPA 70 except
where it is required or recommended to be otherwise in this UFC or by the project
documentation. Stranded-copper-wire ground conductors, sized in accordance with
NFPA 70, should be used to interconnect equipment enclosures and the ground
system. Several methods of ground systems are typically used on Navy piers and are
identified below as examples. These methods tie into an "onshore ground rod system"
at the head of the pier. Where an "onshore ground rod system" is not applicable, an
"alternative ground" system as indicated below, must be utilized.
3-8.8.1
Water Piping Ground. The metallic water piping on a structure can be
used as a ground for electrical-equipment enclosures on the structure. However, the
effect of this usage on the cathodic protection system (if present) for the water mains
must be explored. If adverse effects are possible use a different method.
3-8.8.2
Pier Structure Ground. The pier structural steel system may be used as
part of the grounding system for electrical equipment enclosures on the structure. This
method, utilized on the double-deck Pier 6 Replacement Project in Norfolk, connected
exothermically welded # 4/0 bare copper conductors from the structural steel rebar to
threaded 13 mm (1/2 in) inserts. These inserts were located near the electrical
equipment, as required, throughout the pier on the ceiling or walls. Ground bars or
individual ground conductors were then attached to the inserts.
3-8.8.3
Alternative Ground. Where it is not practical to properly maintain an
"onshore ground rod system" adjacent to a pier, provide metal plates laid under water
and on the bottom of the associated body of water. The conductor connecting these
plates should be at least No. 2 AWG stranded copper wire. In addition, ground systems
for waterfront structures that have gasoline piping systems should be designed in
accordance with MIL-HDBK-1022A.
3-8.9
Pier Lighting. Information on pier lighting is available in UFC 4-151-10,
General Criteria for Waterfront Construction.
3-8.10
required. Coordinate with the cognizant NAVFAC EFD/EFA OR USACE DISTRICT.
Design in accordance with MIL-HDBK-1004/6, Lightning Protection, and NFPA 780,
3-65
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