CHAPTER 8. SHIP-TO-SHORE DISCONNECTION
8.1.1 HOSE FLUSHING. Before a vessel gets under way, it places its CHT
system in the holding mode and stops pumping ashore. The steps necessary
for disconnecting sewage hoses begin by flushing the hoses with salt water.
This function is performed by admitting high-pressure salt water from the
ship's fire-fighting system into CHT discharge piping. Salt water then flows
through the ship's piping to the open discharge riser, through the hose, and
into the sanitary sewer.
The flow of salt water dilutes and flushes away sewage remaining in
piping and hoses after pumping ashore has stopped. The volume of salt water
flow should be high enough to flush the hoses full bore, and the flushing
should continue for at least 10 minutes. By the end of that time, the inte-
rior surfaces of the hoses should have been flushed by several thousand gal-
lons of salt water. Experience at San Diego shows that a significant reduc-
tion of bacteria counts results from a proper salt water flushing operation.
8.1.2 FLUSHING PROCEDURES.
a. Surface Vessels. All class ships in the Navy other than the DD963
have the hose flushing capability. The following steps are carried out by
ship and shore crews for proper flushing of sewage hoses before disconnec-
(1) The sewage discharge hose(s) remains in place throughout the
salt water flushing procedure; the pier sewer riser valve remains open, and
the CHT riser discharge valve aboard the vessel remains open.
(2) The ship crew aligns the CHT system for sewage holding and
secures sewage pumps; 40 psi salt water is then admitted to the CHT discharge
piping from the ship's fire-fighting system for flushing out piping and hoses
with salt water.
(3) The ship's crew flushes the sewage hoses with salt water under
full pressure for 10 minutes, or until the shore crew requests that the
flushing be stopped. The shore crew observes the manner in which the flush-
ing water is passing through the hose during the procedure. If a full bore
discharge is not obtained, the shore crew closes the pier riser valve until
a full bore flush is achieved. Flushing of the hoses can be noted by feeling
hose pulsations during the operation.
(4) At the conclusion of the 10-minute period, the ship's crew
secures the salt water flush aboard vessel and closes the riser valve on the
ship's CHT discharge; this completes the flushing procedure.
a ship does not have the capability of flushing its
discharge line and
the transfer hose with salt water for a minimum of 10
minutes, the shore
crew should recover the hose, connect it to the nearest
salt water outlet,
and flush the hose into the harbor with a full bore high
pressure flush for