12 December 2001
"Ship motions analyses of the remaining home ports and shipyards will be
completed...after receipt of funding." The motion analyses that NAVFAC
prepared for Mayport and San Diego predicted days of access and
generated nomographs for other locations. For channels subjected to
significant waves, engineers and planners must evaluate these wave
effects on ship motions.
Therefore, as provided for in Appendix B, facility engineers and planners
should determine dredge depth requirements by including the additional
considerations of design water level, channel width and ship speed
impacts, dynamic effects of sea chest intake fouling, and wave effects.
Additionally, they should include effects from sedimentation and dredging
The requirements provide consistency and reliability in the determination
of acceptable dredge depths for channels and berths used by active Nimitz class
aircraft carriers. The NAVFAC Criteria Office will address reserve status condition of
CVNs when required. Deviation from minimum criteria requires a waiver from the
NAVFAC Criteria Office which will be coordinated with cognizant Major Claimants,
Naval Sea Systems Command, and Chief of Naval Operations.
Ideally, engineers and planners should base ship channel designs on
physical model testing, risk analysis, and ship simulator analysis. However, time and
funding constraints may prevent this process. In any event, the requesting activity
should determine the required dredge depths for Military Construction Projects. Dredge
depth requirements for Nimitz class aircraft carriers depend on the type of waterway to
be dredged. Four categories exist based on the magnitude of wave-induced and
speed-induced ship movement:
Outer channels entrance channels or waterways subject to significant
wave action, that is, wave energy resulting in vertical ship motions greater
than 0.5 ft. under design conditions.
Inner channels interior protected channels or waterways subject to
minimal wave action, that is, wave energy resulting in vertical ship motions
less than 0.5 ft. under design conditions.
Berths water areas where ship velocity approaches zero, such as
anchorages, slips, and pier and wharf berths that are subject to minimal
wave action under design conditions; generally includes turning basins
except as noted below.
Special berths defined as berths subject to significant wave action under
The following definitions apply: