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Gear Test: WaterWitch bilge alarm

We all know it’s crucial to keep the water on the outside of the boat, so it’s important to be aware of the water level in the bilge.

We all know it’s crucial to keep the water on the outside of the boat, so it’s important to be aware of the water level in the bilge. Installing at least one high-water alarm in the bilge obviously is a must, but a single monitoring point doesn’t always indicate a deteriorating condition until it has become a major concern. For example, the limber holes that allow free water transfer between bilge compartments can become plugged.


When a high-water bilge alarm activates aboard my trawler, I want to know which hatches to pull up the first time, without trying to determine at which end of the boat to begin. The WaterWitch WW600 Multi-Bilge Alert can monitor up to six separate bilge compartments when automatic bilge pump switches, such as the WaterWitch Model 101, or conventional float switches are installed. The WW600 alerts you to high bilge water both audibly and visually on its panel face through a series of warning lights. The electronic panel includes a test button, six backlit compartment indicators, and a 1/4-inch hole for the audible alert tone. The WW600 also incorporates an intelligent mute switch that allows you to temporarily silence (but never permanently disable) the audible alarm feature of the panel.

Using the well-written and illustrated instructions, the WW600 is easy to install and operate. Installation requires a cutout measuring 2-3/4 inches high by 3-3/4 inches wide; the finished faceplate dimensions are 3-1/4 by 4-1/2 inches. While the panel is only 2 inches deep, including wiring terminals, WaterWitch recommends a mounting-depth clearance of 3 inches to allow for gentle wire bends and proper terminal connections. Electrical connections are made to the unit’s threaded brass studs, which are clearly marked, and should be made with closed-end ring terminals.

When power is applied to the system, the alarm pulses four times and the panel flashes, indicating that the unit is functioning. It then goes into standby mode. When there is an alert condition, the corresponding compartment light goes, and the alarm pulses for as long as the condition exists. The audible alarm is produced by a stainless steel piezo buzzer that registered 78 decibels three feet from the panel. Unfortunately, depending on the panel location and ambient sound level on board, the alarm may be difficult to hear.

The Inteli-Mute system is a feature that separates the WW600 from other bilge alarms. It activates once the mute button is pressed and eliminates the risk of accidentally leaving the system muted. Inteli-Mute silences the audible alarm while leaving the backlit mute button flashing as a visual reminder and the compartment indicator illuminated. The system then waits five minutes to check if an alarm condition still exists. If it does, Inteli-Mute reactivates the audible alarm warning. If the cause of the alarm no longer exists, the system resets. If a second alarm condition is detected while the system is muted, Inteli-Mute reactivates the audible alarm to warn of the new condition.

In addition to the internal alarm, the WW600 has an auxiliary output rated at 5 amps that can be used to power external lights, flashers, additional audible alarms or remote vessel monitoring systems for relaying the alert condition.

I wired several styles of pump switches to the WW600, including the WaterWitch Model 101 automatic bilge pump switch. The WW101 has no moving parts. When it senses water across its stainless steel contacts, it transmits electrical impulses to activate the pump or alarm. I prefer this style switch to conventional float switches, not only for their reliability (lack of moving parts) but the fact that hydrocarbons (oil and fuels) won’t activate it. The WW101 switch has a versatile mounting tang that allows convenient installation on virtually any bilge pump or compartment location. As expected, all the switches worked well with the WW600 alert panel.

I found the WW600 to be well designed and constructed and easy to install. It functions as advertised and will certainly be included on my “must have” list. The WaterWitch WW600 Multi-Bilge Alert is available with black or white panel faces, in both 12-volt DC and 24-volt DC configurations. The 12-volt model lists for $146.22, while the 24-volt model lists for $154.22. The Model 101 bilge pump switch lists for $29.99. All products are available directly from WaterWitch at , or at most major chandleries.