RV Water Tank Guide: The 3 Main Water Tanks

Posted by RVCampersUSA on Nov 2nd 2016

If you're new to RVing, you'll want to familiarize yourself with the 3 main RV water tanks pretty quickly. Get started here.

3 main rv water tanks

RVs have several different water tanks, each of which is intended for a specific purpose. Whether you're thinking of buying or renting an RV, it's important to familiarize yourself with these water tanks. Otherwise, you may end up creating a haven for bacteria and bad germs in the process.

The 3 Water Tanks in RVs

While there are a few exceptions to this rule, most RVs have three water tanks: clean water (also known as potable water), black waste water, and gray waste water. Failure to properly maintain any of these three water tanks can lead to trouble later down the road.

Clean Water Tank

The clean water tank is typically the largest of the three tanks. It's often made of corrosion-resistant metal, although some may feature a plastic like polyethylene.

When filling your RV's clean water tank, you should use a certified potable water hose. This white-colored hose is recommended to avoid cross-contamination with waste water. As such, the potable water hose should ONLY be used with the clean water tank and not the black or gray water tank.

Black Water Tank

The black water tank is where waste water from the toilet drains. You should never attempt to drain your RV's black water tank in a non-approved dumping site. Not only this is bad RV etiquette, but it could land you with a hefty fine, as most places have laws requiring RV operators to dump their black water in designated areas.

Furthermore, you should leave the black water tank drain valve closed until it approaches its maximum capacity. The general idea is to allow the solids ample time to break down so the water can be emptied more easily when you finally open the valve.

Gray Water Tank

The third type of RV water tank, gray water, is waste water that comes from the bathroom and kitchen sink. It's stored in a separate tank because it doesn't contain human waste.

Hopefully, this guide will give you a better understanding of the different water tanks used in RVs. Most RVs have three basic water tanks: one for the clean (potable water), another for the toilet water (black water), and a third for the gray water (kitchen and bathroom sinks). Refer to your RV's owner manual for more information about its respective water tanks and how to properly maintain them, click here for tips.