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These days, boats are not just used for transportation. Many people use boats as their primary home, which begs the question: Where do houseboats dump sewage?
Most boats will have their sewage pumped out of their septic tanks when they dock at the marina, for a fee. Others may throw their sewage into the ocean or waterways, in compliance with the country’s laws.
When it comes to living a life of freedom in a houseboat, dumping sewage is not something that you want to think about. However, it is necessary. Just consider what would happen if you were expecting guests on your houseboats only to realize that your sewage facilities are full.
Since I have been using a houseboat as my primary home for over a decade, I feel I am uniquely qualified to answer the question of what to do with your sewage when you live on a boat, in compliance with the Environmental Protection Agency. Let’s discuss it in detail.
Pumping Out Sewage at a Sewage Station or Marina
The most common way for houseboats to empty out their sewage tanks is to get them pumped out when they dock at a marina or sewage station. Since most houseboats are used for recreation purposes, they will need to only empty their tanks at the end of the season.
If a bigger family is living in a houseboat or if you use the houseboat as your primary residence, the sewage tank will need to be cleaned out on an as-needed basis.
Most marinas have specifically designated spots where houseboats can park and get their septic tanks pumped out. These marinas charge a small fee for the service. Depending on how much your kitchen and bathroom facilities are used, you will need to determine how soon you will need to empty them.
When to Empty Your Tanks?
Some people only have to empty their tanks once a season while others will need to empty their sewage tanks every few weeks or once monthly. The frequency varies from houseboat to houseboat and depends on the usage of the sewage facilities, so you will need to determine what works best for you.
I strongly recommend that you have a fixed schedule to arrive at a marina or sewage station once you find out how long it takes to fill up the septic tanks. A good idea to calculate this is to figure out the average number of days it takes to fill the tank and then empty them two or three days before they become 100% full. This way, you can be sure you always have working facilities, even if you are expecting guests and have used the bathroom and kitchen facilities more than usual.
You do not want to end up with an overflowing sewage tank and have to clean up the mess!
Dumping Sewage Into the Ocean
The second place to dump your raw sewage is in the ocean. There are many countries that have a law against dumping sewage into rivers, lakes, and other inland waterways. However, you can still dump untreated sewage into the ocean if you are over three miles offshore.
What If I Have to Dump My Sewage Within Three Miles?
Any sewage that needs to be discharged within three miles offshore needs to be treated using a US Coast Guard-approved marine sanitation device. There are three types of MSDs: Type I, Type II, and Type II. Typically vessels that are up to 65 feet in length require only Type I MSD devices.
Type I MSD devices pulverize the solid waste and expose the waste to disinfectants, like chlorine tablets. These disinfectants can reduce the level of bacteria in the waste to below the acceptable limits under the Clean Water Act. Some devices are specially designed to create antiseptics from the saltwater so you do not have to add any disinfectants separately.
What If I am in a No-Discharge Zone?
A No-Discharge Zone is an area in the water where boats and ships cannot discharge treated or untreated sewage. If your houseboat is in a no-discharge zone, you absolutely cannot flush out your septic tanks there. Doing so can result in a hefty fine. You need to secure your MSD to prevent discharging the wastewater and sail your boat into waters where sewage dumping is allowed or dock yourself at a marina.
Although it seems quite disgusting that you can dump untreated sewage into the ocean just a few miles offshore, the movement of the water does not allow this waste to float back to the shore. In addition, the sewage is either decomposed by bacterial activity or is eaten.
Even large commercial vessels are allowed to throw some of their sewage into the oceans, albeit with several restrictions.
Dumping Sewage into Waterways
It is prohibited to dump black water into rivers, lakes, and inland waterways; however, houseboats that do not venture out into the ocean are allowed to dump grey water into the waterways.
Grey water is water used for washing dishes, doing laundry, or showering. This water can be dumped in specific places so you should keep it separate from black water since the restrictions for the latter are stricter.
If your grey water comes into contact with black water, you cannot dump it in any waterways, except at least three miles offshore or at a marine or sewage station. If you violate this EPA standard, you can be fined up to $2,000 for each violation. This means if you even get caught once, you will have to pay out money that would have been better put to use dumping your sewage at the marina over several years.
Should Houseboats Dump Sewage In the Water?
Ultimately, the sewage from houseboats needs to go somewhere. For houseboat owners, I recommend that they should have two separate septic tanks for grey water and black water. Doing this can allow you to go longer between sewage dumps and pumps and can help you better abide by the law set out to conserve the aquatic ecosystem.
Where it is allowed, you can dump grey water into the rivers and lakes. This can help you save time and money from having to dock at a marina and have your septic tank pumped out. In addition, grey water is not as dirty as black water and is even often cleaner than the water your houseboat is sailing in, so dumping that in waterways will not harm the environment.
For discharge of black water, we recommend that you wait until you arrive at a marina or sewage station that has the right equipment to empty your black water tank.
Keep in mind, though, that in many areas of the world, the laws about dumping black water are quite different. If you are venturing outside of the USA, make sure you understand the laws of that country pertaining to sewage disposal as well as other boat-related activities.