Plumbing and pumps are the systems that work hardest and are seen least. One day a bilge pump saves the boat; a badly installed sanitation system is felt every day.
Bilge
- An electric pump and an independent manual pump.
- Float switch and alarm; a high-water alarm.
- Strainer at the intake and check valve; the discharge looped above the waterline.
- Capacity: ISO 15083 for bilge pumping systems.
Sanitation
- Odour-resistant sanitation hose.
- Holding tank vent and filter.
- Y-valve and routing; use in line with discharge rules.
- Pump and macerator.
Fresh and seawater
- Pump and accumulator; frequent cycling when leaking.
- Strainer and valve at seawater intakes.
- Hose and clamp materials.
When renewing
Hoses are renewed system by system and dated; every joint below the waterline is double-clamped. Pumps are mounted where they can be reached, with room for servicing.
Choosing hose
Not every hose aboard does the same job. Seawater lines need reinforced hose suited to seawater; drinking water needs food-grade hose; sanitation needs odour-resistant sanitation hose; fuel needs certified fuel hose. The wrong hose soon hardens, smells or leaks. On renewal, each line's hose is chosen for its job and marked with the renewal date.
Choosing pumps
Bilge pump capacity is chosen for the boat's size and bilge volume, but real capacity falls with hose length, lift and bends. So pump and line are assessed together. Alongside the electric pump, a manual pump that works when power fails is a basic safety measure.
High-water alarm
Even with a working float switch, a separate alarm when bilge water rises gives early warning if the pump cannot keep up or has failed. It should be audible at the helm and in the sleeping areas.
Sanitation and rules
Emptying the holding tank follows local rules. In a marina a pump-out station is used; whether discharge at sea is allowed, and at what distance, varies from region to region. The Y-valve's position and locking matter for compliance.
Acceptance
After renewal, every line is checked for leaks under pressure and running; pumps are run and the alarm tested.
Records
A simple diagram of the plumbing, with valve positions and hose dates, goes into the handover file; it makes fault-finding and the next renewal far easier.
Access
Pumps and strainers are mounted where they can be reached and cleaned without removing joinery.
At lay-up
At lay-up, fresh water and sanitation lines are drained or protected against frost; at the start of the season they are refilled and checked again for leaks, with every clamp looked at once more.
On survey, each pump is run, the float switch lifted by hand, hoses checked for hardness and clamps for condition, and joints below the waterline checked for double clamping.
Sanitation on survey
In the sanitation system, odour, tank venting and the Y-valve's position are examined, and findings are written into the report with their grades. Because plumbing works out of sight, regular checks and records are the habit that most decides how long the system lasts.
A diagram and a dated hose list are the two documents that make every future plumbing job faster, cheaper and less likely to be done wrong by the next tradesman who opens a locker.
Replacing hoses on a schedule, rather than when they fail, turns an emergency into a routine job done in comfort at the yard.
Date every new hose when fitting it.
A marker pen and thirty seconds per hose is all it takes, and it tells the next owner or surveyor exactly how old every hose aboard really is.