Safe Drinking Water Offshore

---

We are often asked to comment on the design, construction or repair of potable water systems on ships and offshore structures. Discussions inevitably lead to the review of guidelines and standards commonly applied drinking-water quality.

There is a wealth of information published by various organisations. Nearly all guidelines and standards have a set of common principles regarding the management of drinking-water systems. One of the most useful summaries comes from the Australian Drinking Water Guidelines:

Ensuring drinking water safety and quality requires the application of a considered risk management approach.

The greatest risks to consumers of drinking water are pathogenic microorganisms. Protection of water sources and treatment are of paramount importance and must never be compromised.

The drinking water system must have, and continuously maintain, robust multiple barriers appropriate to the level of potential contamination facing the raw water supply.

The multiple barrier approach is universally recognised as the foundation for ensuring safe drinking water. No single barrier is effective against all conceivable sources of contamination, is effective 100 per cent of the time or constantly functions at maximum efficiency.

Robust barriers are those that can handle a relatively wide range of challenges with close to maximum performance and without suffering major failure. Although it is important to maintain effective operation of all barriers, the advantage of multiple barriers is that short-term reductions in performance of one barrier may be compensated for by performance of other barriers.

Providing a disinfectant residual throughout the distribution system can provide protection against contamination and limit regrowth problems.

Prevention of contamination provides greater surety than removal of contaminants by treatment, so the most effective barrier is protection of source waters to the maximum degree practicable.

System operators must maintain a personal sense of responsibility and dedication to providing consumers with safe water, and should never ignore a consumer complaint about water quality.

System operators must be able to respond quickly and effectively to adverse monitoring signals.

Supporting Documents

• Guide to ship sanitation, 3rd Edition, 2001, World Health Organization.
• Guidelines for Drinking-water quality, 4th Edition, World Health Organization.
• Safe drinking-water from desalination, 2011, World Health Organization.
• Safe piped water: managing microbial water quality in piped distribution systems, 2004, IWA Publishing on behalf of the World Health Organization.
• Water safety plans: managing drinking-water quality from catchment to consumer, 2005, World Health Organization.
• ISO 15748-1:2002(E), Ships and marine technology; Potable water supply on ships and marine structures; Part 1: Planning and design.
• Australian Drinking Water Guidelines 6, 2011, Version 3.3, Australian Government.
• Safe, sufficient and good potable water offshore, 3rd Edition, 2013, Norwegian Institute of Public Health

Marine Plant Systems services our equipment brands.  Service scope includes installation assistance, commissioning, troubleshooting, inspection, maintenance and calibration verification.  

Contact us to learn more about our sales and service capabilities.