How to Measure Water Level in your Rain Barrels

We get this question a lot: How do I measure water level in my rain barrels?

If you've tried to guess how much water is in your rain barrels, you know that the "tap test" and "temperature feel" aren't as easy as we'd hope. Here are a few ways to pinpoint the water level in your BlueBarrel System™ to the tee!:


Tank Gauge

One of our most popular system accessories is the Tank Gauge by Rain Harvesting.

It monitors the water level in your BlueBarrel System™ with an easy-to-read dial. It is quick and easy to install, and uses a non-numbered "Empty-to-Full" scale so it will work with tanks of any size (up to 100" in height)...and BlueBarrel Systems with any number of barrels.

With the BlueBarrel System's unique under-plumbed design, your water level will be the same in all barrels, so you only need one Tank Gauge for each multi-barrel system. (With other multi-barrel designs, you may need a gauge on each barrel as each may have a different water level).

Find the Tank Gauge in our Online Store. You can order it along with your DIY RainKit™, or on its own under Tools & Accessories.


Liquid Level Sensor

Liquid Level Sensor

A more precise method is to use a Liquid Level Sensor.

This tool is a little more costly, but it works like a stud finder to call out the level in your barrels. It beeps and lights up with a level display of lights to pinpoint the water level in your tanks.

If you have separate tanks or systems on different downspouts, or if you're using valves close off parts of your BlueBarrel System (our design allows people to hold water in some tanks for emergency storage while draining others for irrigation), this tool is well worth it to get quick and accurate measurements on every barrel.

Find the Liquid Level Sensor in our Online Store. You can order it along with your DIY RainKit™, or on its own under Tools & Accessories.


Hand-Crafted Sight Level Gauge

Or you can go the DIY route. Here's a quick guide for how to build a sight glass, or sight level.

Clear Level Gauge

Because of the leveling function of BlueBarrel's unique under-plumbed design, all barrels in a BlueBarrel System will maintain the same water level. By installing a clear tube into the same plumbing line that connects the barrels, you can read your water level by observing the water level in the clear tube. Our customer, Randy, from Sacramento, CA shared photos of his creative self-made water level gauge.*

PLEASE NOTE: the top of the tube needs to be vented so that water can enter the tube without trapping air. And as with all openings on a rain collection system, the vents should be protected with 1/16" mesh to prevent mosquito breeding and entry of large particulates.


*As a quick caution - a clear level gauge is often the weakest part of a rainwater collection system. If it cracks or leaks, all of the water in your BlueBarrel System will be compromised. If you decide to craft your own level gauge, be sure you use durable materials that will give you a good fit and a tight seal! Make sure to keep a clear gauge shaded at all times, as exposure to sunlight will lead to algae growth. (Blue barrels are opaque and UV resistant, so no worries about algae in your BlueBarrel System otherwise!)

Check out this video for a water-level demo.
For photos of this installation and more, visit our online photo gallery!