We all know those smells and how they affect our time on the boat. No one wants to spend quality time working on your boats head (toilet for you land lubbers!) We’d all much rather be on the water enjoying the day.
Head odors can be caused by a number of things. The biggest culprits are; Using raw water for flushing, old permeated hoses, lack of airflow in the holding tank, mixing of waste products, lack of beneficial bacteria in the holding tank, not pumping out the holding tank often enough and mechanical issues with the head.
Unfortunately many of use have an electric flush head that draws raw seawater from a through hull located somewhere on the boat and uses that water to flush the head. This introduces all kinds of bacteria and elements to the sanitation system that can and will cause odors. If you have this setup, there are a few tricks you in order to help keep the smell down.Flush using freshwater once a day. I use the shower head to fill the head and flush it every time I shower on the boat. Flush or use the head daily, this helps keep the water from becoming stagnant in both the pickup hose and the hoses that lead to your holding tank. The longer the raw water sits without being oxygenated the more anaerobic bacteria grows and creates odors. This odor is typically a sulfur like smell. You can disconnect the raw water intake and with proper check valves and anti siphon devices hook the head intake to your freshwater tank. Another option is to replace the electric flush head with a vacuum flush system that uses freshwater only to flush the head. A concern with this set up is contaminating your freshwater system with wastewater from the toilet, either through failure of a check valve or from a siphon created when the water tank is lower than the head. There are industry standards regarding hooking up a fresh water tank to a sanitation system. Another concern with tying into the freshwater system is over using your fresh water for flushing the toilet. In some areas and for some long range cruisers water is an important and expensive commodity. Adding freshwater flush capability will improve many foul odor issues drastically.
Sanitation hoses are another common area odors originate from. Make sure you have marine grade impermeable sanitation hose installed on your boat. Even impermeable hose will allow odors to leach out after a few years of use. I’ve read recommendations that say to replace your sanitation hose with high quality hose every 4-5 years. Waste sitting in low spots along the hose can and will permeate through the hose. One account I read from a boat owner claimed just replacing the hose eliminated almost all the waste odors from her boat. To test if your sanitation hose is causing odors on your boat wet a clean rag with very hot water and wrap it around a low section of hose and leave it on the hose until it cools. Remove the rag and sniff it. If you smell any bad odors on the rag it’s time to replace the hoses.
The boating community is never short of debate and differing ideas on what works no matter the topic. The next item on our list is a hotbed of debate amongst many boaters. A holding tank with poor airflow will be a hotbed of odors from anaerobic bacteria that thrive in low oxygen environments. To tackle this you want to make sure your vent lines to the holding tank are adequate and unclogged. Vent lines can become clogged from the waste itself when the tank is overfilled or from spiders or other things crawling into the vent and setting up a home. A good charcoal filter on the vent line also helps with odors outside of your boat. Now, the debatable item. A newer trend is to install an aerator pump to the holding tank and aerating the waste 24/7. From what I’ve researched and read most people claim aerating the waste tank eliminates most of the odors emanating from it. The detractors claim it is unnecessary and a waste of battery power. Either way large 1 inch vent hoses or an intank aerator both will help encourage aerobic bacteria to form and digest the waste in the tank. Aerobic bacteria are good for the health of the sanitation system. Using bleach or other products that kill germs may reduce the level or kill off all the good bacteria in the system.
Anyone that has a composting head will tell you they are great until you mix the urine and feces. Poop by itself in the composting head doesn’t smell all that bad but if you mix urine into the equation you end up with horrible smells. Anyone that has used a camp toilet or composting toilet in years past can relate to the horrible smells. New composting toilet designs keep the pee from the poop. They use a urine diverter to store the urine in a separate detachable container from the main waste receptacle. Installing a composting head in most cases and when used properly will eliminate most head odor issues. I am considering replacing my head with a composting head for these reasons.
Waste shouldn’t be in your holing tank long enough to set up shop and start stinking. Pump the holding tank out frequently and before leaving the boat sit unattended for any length of time. The simple act of having the tank pumped and flushed will drastically reduce odors plus who wants all that stuff sitting around anyhow. After pumping the tank out flush the tank with water a few times and pump it empty. Adding a few capfuls of liquid fabric softener to the tank while washing it out will help make it so waste doesn’t stick to the sides and bottom of the tank.
A poorly maintained head and tank can also contribute to odors. Duckbill or joker valves need replacing and can be damaged by using household chemicals to clean the head. Seals and tank fitting can leak into the bilge and cause boat wide odors. Check and maintain your head and tank, inspecting the system often. Never use bleach or other caustic chemicals to clean the head or tank as they can breakdown seals and parts. If needed vinegar is a decent alternative to bleach.