f. Turning Basin Criteria 2200 ft (optimal)/1650 ft (absolute minimum with full tug
support) radius. Tug availability should be considered. Minimum depth = 49.5 ft. at Mean Lower
Low Water (MLLW) and 45.5 ft at Extreme Low Water (ELW) with no waves as explained
g. Minimum Inner Channel Width (inside breakwaters) 600 ft. min. at toe of slope,
assuming no bends in the channel and no other traffic during transit. Narrower widths may create
maneuverability difficulties, increase risk of grounding, and increase sinkage thus reducing
efficient homeport operations.
a. Minimum slip width - 600 ft. with no other ships, 800 ft with CVN on opposite berth.
Add 100 ft to width if ships are berthed at the bow or stern also.
b. Minimum slip depth - 49.5 ft. min. at Mean Lower Low Water (MLLW) and 45.5 ft.
min at Extreme Low Water (ELW). The requirement at MLLW is based on preventing fouling of
sea chest intakes. The requirement at ELW is based on preventing grounding. Over time,
siltation occurs in most slips and should be quantified initially. The design depth should then be
deeper than the minimum to accommodate siltation. Siltation may be mitigated through advance
maintenance dredging or other means. These depths provide protection against condenser fouling
and grounding, and accommodate variability in displacement, list and trim. More detail is
contained in "ITG CVN Dredge Depth Criteria," NAVFACENGCOM, dated 4 March 1997.
The ITG includes NAVSEA ltr 11460 Ser 03D3/242, dated 3 Jan 95, "CVN 68 Class Water
c. Minimum slip length - 1300-1325 ft. min. This range in slip length provides adequate
space for bow and stern lines, provides a safety clearance fore and aft of 100 ft., and facilitates
emergency sorties without tug support. However, five to eight tugs should be available for
d. Arrangement CVN's are typically moored "starboard-side-to" to allow access to the
ship's three elevators for on/off loading.
Tides and Currents
a. Tides - avoid locations subject to tides greater than 10 ft. Location subject to tides
greater than 10 ft. are functional but incur increased operational costs due to increased line
tending, utility connection fatigue, and fender degradation.
b. Currents - avoid locations subject to average broadside currents greater than 3 knots.
Moorings on Naval vessels are typically designed to resist up to 3 knot current. Local eddies can
also make mooring difficult.