Maintenance Of Fresh Water

Fresh Water Loading and Supply Arrangements :

Fresh water obtained from shore mains supply or water barge should be transferred by a designated fresh water hose. Hoses should be durable, with a smooth, impervious lining, and equipped with fittings, including adapters to permit connection to the shore potable water hydrants and filling connections to prevent their use for loading other liquids. Hoses should be:

1. clearly marked (generally colored blue)

2. stowed in a locker clear of the deck

3. drained and capped at both ends after use

4. flushed through and discharged to waste before loading

Often ships use quayside hoses, in which case a designated crew member should ensure that such hoses are in good condition and that they are routinely disinfected, safely stowed and capped in a clean environment.

Every potable water tank should have a filling line to which a hose can be attached. This line should not be cross-connected with any line on a non-potable water system. Each line should be clearly identified as such and painted blue with a screw cap or plug fastened by a short chain so that the cap does not touch the deck when hanging free.

Persons inspecting or working in fresh water tanks should wear clean protective and footwear which has not been used for any other work area and they should not be suffering from any skin infection or communicable disease.

Monthly / Accordingly to Manufacturer	Filters Clean / Change UV exposer area clean
3 monthly	Shower heads ( Particularly in accommodation that has been out of use for an extended period ). Clean in a 50 ppm chlorine solution.
6 monthly or more frequently if required	Flush and fill with 50 ppm chlorine solution and allow to stand for at least an hour before emptying and stowage.
6 monthly	To be thoroughly pumped out and where necessary hosed prior to refill.
12 monthly	To be opened up, emptied, ventilated and inspected and thoroughly cleaned, recoated as necessary, aired and refilled with clean fresh water chlorinated to a concentration of 0.2 ppm free chlorine. The cleaning process should include disinfection with a solution of 50 ppm chlorine.
Periodically ( General recommendation – annual inspection)	Calorifiers : To be opened up, inspected, scaled and cleaned. Before draining temperatures should be raised to 70 C for at least an hour to ensure destruction of bacteria which may have colonized the lower and cooler zone of the unit.
Refit or Dry Dock	The system ( from machinery space to furthest outlets ) should be charged with super-chlorinated fresh water at a concentration of 50 ppm for a period of 12 hours then completely flushed out and refiled at 0.2 ppm residual free chlorine.
Interval not greater than 5 years	Pressure tests on all FW tanks ( After the pressure test, the system to be thoroughly flushed with potable water)

Note : It is the summery of fresh water maintenance from MSN 1845.