Jack Meyer, Houston, TX USA asks:
Questions: My wife and I are planning to make the leap in 10 to 12 years after our daughter is out on her own. In the meantime, I intend to educate myself as much as possible. As I go through the mental exercise of how a boat should be set-up, I wanted to ask you if you think it necessary to have two water makers. I believe in keeping things as simple as possible, and would prefer to only have one watermaker, but if they break down frequently, it would make sense to have a backup. I was just wondering what your real life experience is concerning this issue.
Thanks
Jack Meyer

Scott Flanders from Egret responds:
Jack, I believe if you looked deep into the heart of most every cruiser with a watermaker you'll find a love/hate relationship. For coastal cruising with a couple you don't need one. Every week or two it is easy to go to a dock and fill up. If you do choose to go this route (of not getting one) have the manfacture install the plumbing and wiring to the space where you can later install a watermaker. You'll pat yourself on the back time and again if you don't have to do a complete installation down the road. We put a watermaker in during commissioning. We used it little except for Bahamas cruising the first two winters (where it was necessary). Once leaving the States we have used it extensively, pickling it during our two winters in the Med.

In ten years watermaker technology will probably advance little. RO (reverse osmosis) technology is a relatively simple process of pumping seawater aboard with an inlet pump to supply the high pressure pump that in turn sends it through the membranes. You retain about 10% fresh water, discharging the balance. The complexity of watermakers is the electronic devices to 'simplify' usage. When the electronics hiccup its a problem. We bought a very simple system for Egret, a Matrix Emerald 600 system. 25GPH. Even that simple system has an electronic solenoid valve that sends RO water to the tank after it determines the PPM (parts per million) levels are adequate. Our valve failed after five years. We now have re-plumbed the system to a manual system sending ALL RO water directly to the tank. We have used the watermaker enough we are very familiar with how long it takes to get 'pure' water and don't feel it is a problem to send the very slight amount of 'not to standard' water directly to the tank.

We backflush with water from our tank every 4-5 days while on anchor here in Ushuaia's polluted harbor. Before we use the watermaker again we'll remove the watermaker hose to the fresh water tank manifold and let it run into the shower for 5 minutes or so before hooking it back up to feed the fresh water tank. We also have a hand held PPM meter so we're not flying blind (we bought ours from WW Grainger). Nordhavn furnishes a very good stainless steel water manifold with valves (including spare valves) to isolate water in/out when you are working on whatever. Our manifold is located under a hatch in the master stateroom across from the head/shower.

A secondary advantage of a watermaker is it loads the generator while you are charging the batteries. In the cold water here in the Deep South, without the watermaker we can't bring the generator to load using just the reverse cycle air conditioners. We waste water (looooong hot showers, etc) in order to be able to use the watermaker nearly every day outside the harbor.

Bottom line: Save your money and installation space unless you plan to build a very large boat and install a single, simple watermaker. Spend your money for a second, smaller radar, GPS, autopilot, spares and so forth. Ciao.