Building a custom water storage system
Building a custom water storage system

Ensure your family's health and well-being while at sea by building a custom water storage system for your boat and generating fresh water from seawater.

Building a Custom Water Storage System

As you embark on your sailing adventure, one of the most important aspects to consider is your water storage system. Ensuring you have a reliable and efficient water supply is crucial for the health and well-being of your family while at sea. In this article, we will discuss the importance of a custom water storage system, the different types of watermakers and desalination systems available, and how to build your own custom water storage system to suit your needs.

Table of Contents

Why a Custom Water Storage System is Important

When living aboard a boat, access to fresh water is essential for drinking, cooking, and hygiene. While you can store a certain amount of water on board, it is not always feasible to carry enough for extended periods at sea. This is where a custom water storage system comes into play.

A custom water storage system allows you to generate fresh water from seawater, ensuring you have a constant supply of clean water for your family. By building a custom system, you can tailor it to your specific needs and preferences, ensuring it is efficient, reliable, and easy to maintain.

Types of Watermakers and Desalination Systems

There are several types of watermakers and desalination systems available, each with its own advantages and disadvantages. Let’s take a look at the most common options.

Reverse Osmosis

Reverse osmosis (RO) is the most popular method of desalination for boats. It works by forcing seawater through a semi-permeable membrane, which filters out salt and other impurities. The result is clean, fresh water that is safe to drink.


  • Highly effective at removing salt and impurities
  • Produces a large volume of fresh water
  • Compact and relatively easy to install


  • Requires a significant amount of energy to operate
  • Can be expensive to purchase and maintain
  • Membranes can be sensitive to fouling and require regular cleaning


Distillation involves heating seawater to create steam, which is then condensed back into fresh water. This process effectively removes salt and other impurities, leaving you with clean drinking water.


  • Effective at removing salt and impurities
  • Can be powered by waste heat from your boat’s engine or other sources


  • Requires a significant amount of energy to operate
  • Can be slow to produce fresh water
  • Larger and more complex systems compared to reverse osmosis

Solar Stills

Solar stills use the sun’s energy to evaporate seawater, which is then condensed back into fresh water. This is a passive process that requires no additional energy input, making it an eco-friendly option.


  • Environmentally friendly and energy-efficient
  • Simple and low-maintenance


  • Slow to produce fresh water
  • Dependent on sunlight, making it less reliable in cloudy or overcast conditions
  • May not produce enough water for larger families or extended trips

Building Your Custom Water Storage System

Now that you have an understanding of the different types of watermakers and desalination systems available, it’s time to start building your custom water storage system. Here are the steps to follow:

Step 1: Assess Your Needs

Before you can design your custom water storage system, you need to determine your water needs. Consider the following factors:

  • How many people will be on board?
  • How long will you be at sea between stops to refill your water tanks?
  • What is your daily water consumption for drinking, cooking, and hygiene?
  • Do you have any specific preferences or requirements, such as a preference for eco-friendly options or a need for a compact system?

By answering these questions, you can get a better idea of the type and size of watermaker you will need, as well as the storage capacity required.

Step 2: Choose Your Watermaker

Based on your needs assessment, choose the type of watermaker that best suits your requirements. Consider factors such as efficiency, reliability, ease of maintenance, and cost when making your decision.

Step 3: Design Your Storage System

Once you have chosen your watermaker, it’s time to design your storage system. This will involve determining the size and location of your water tanks, as well as any additional components such as pumps, filters, and plumbing.

When designing your storage system, keep the following tips in mind:

  • Choose materials that are resistant to corrosion and suitable for storing potable water, such as stainless steel or food-grade plastic.
  • Ensure your tanks are properly vented to prevent pressure build-up and allow for easy filling and draining.
  • Consider installing a water level gauge to monitor your water supply.
  • Plan for easy access to your tanks and watermaker for maintenance and cleaning.

Step 4: Install Your System

With your design in place, it’s time to install your custom water storage system. This may involve tasks such as cutting holes in your boat’s hull for tank access, installing plumbing and electrical components, and mounting your watermaker.

If you are not comfortable with these tasks, consider hiring a professional to assist with the installation. Proper installation is crucial for the safety and reliability of your system.

Step 5: Maintain Your System

Once your custom water storage system is up and running, it’s essential to keep it well-maintained. This will ensure it continues to operate efficiently and provide you with a reliable supply of fresh water.

Regular maintenance tasks may include:

  • Cleaning and replacing filters
  • Flushing and cleaning your watermaker’s membrane
  • Inspecting and cleaning your water tanks
  • Checking for leaks and repairing any damaged components

By staying on top of these tasks, you can enjoy the benefits of your custom water storage system for years to come.


Building a custom water storage system is an essential step in preparing for your sailing adventure. By choosing the right watermaker and designing a storage system that meets your needs, you can ensure your family has access to clean, fresh water throughout your journey. With proper installation and maintenance, your custom water storage system will provide you with the freedom and fulfillment that comes from embracing the open sea and spending quality time with your loved ones.