Introduction: Bottom Filled Rain Barrel
Rain barrels can be great source of water for your lawn and garden. They can also cause a great deal of damage if they do not have a reliable water overflow. The water overflow in this design happens inside the downspout diverter. Once the rain barrel is full, additional rain water will overflow inside the downspout diverter and continue down the downspout. This system will fill rain barrels to a predictable level but not overflow the barrel. If you have ever needed to go out and check your rain barrel during a heavy rain storm because you were worried about it overflowing this design is for you.
Step 1: Filling the Rain Barrels
When the rain barrels are not full the water in the diverter’s reservoir drains down the hose. The water level in the hose equalizes with barrel because water seeks its own level.
Step 2: Full Rain Barrels
When the rain barrels are full the downspout diverter's reservoir overflows into the downspout. The water level in the barrel is at the same height as the top of the diverter's reservoir.
Step 3: Working Example
It looks odd to have the downspout diverter below the top of the rain barrel but this is critical to the design. I have used a collapsible section in the downspout to allow adjustment of the diverter height, this directly affects the max filling level in the barrel. It also seems little strange to fill the barrel using the small hole at the bottom but that is also critical to the design and works better that you may think.
Step 4: Downspout Diverter
You will need a downspout diverter that has a garden hose connection to provide a good seal when the barrels are full. Water needs to fill the reservoir in the diverter to the level that will overflow to the downspout below so you need a very good sealed connection to the barrel. Many downspout diverters use their own tubes and clamps that do not have good seals, they should not be used in this configuration.
I have also found that the connection between the diverter and the downspout above the diverter needs to be sealed with some tape. The connection does not need to be super water tight but does need to prevent water from escaping due to the restriction that the diverter has on the downspout. This happens during a heavy down pour.
Step 5: Simple Reliable Garden Hose Connections
Regular garden hose is designed to for pressures exceeding 100psi. In this application the pressure is unlikely to exceed 1psi so it provides very reliable connections between the barrels and the downspout diverter. The connection from the diverter requires a hose with two female connections, I used a connection hose from a washing machine because it is a good length and it has two female ends. I used the cheap rubber connection hoses that came with the our washing machine. You will also need a small extension hose to connect the tee to the rain barrel.
It is also handy to use a hose tee with shutoffs so you can isolate barrels, watering hose or the diverter. Multiple barrels can be added using additional tee connections. Larger 5/8" hose connections may increase the water capturing efficiency but you will need all of the components including the connection to the barrel to be 5/8" in order to achieve the added efficiency. I am sure the small diameter of the hoses I have used restricts the fill rate somewhat but after a rain event the barrel is usually full.
Step 6: Advantages
- Barrels will not overflow
- Barrels do not need a large hole in the top for water intake
- Barrels do not need a large hole in the side for overflow
- Easy to expand to use more barrels (add tee and extension hose)
- Can be implemented with common garden hose hardware designed for higher water pressure (reliable)
- Rain barrels can be positioned away from the downspout with a long hose running on the ground.
- Water is not exposed to mosquitoes
- The tee has a built in valves that can be used to isolate barrels
The bottom filled design takes away the need to have an always down pathway like a stream from the downspout to the rain barrel. Rain barrels no longer need to be located near downspouts so they can be positioned out of sight and away from buildings. Rain barrels can be positioned at a higher point on the property by moving the diverter higher on the downspout eliminating the need for a stand. Each barrel requires only a small hole at the top to allow air in and out and a male hose connection at the bottom. This greatly reduces what needs to be done to a barrel to use it as a rain barrel.
7 months ago
do the barrels need a hole at the top to allow air to escape?
Reply 7 months ago
Yes the barrels are open at the top.
10 months ago
Thanks for the great article -- better than most I've read or viewed on barrels. Two questions:
- What is the advantage of a bottom connection as opposed to a top? What do I gain from inflow to the bottom? If from the bottom, doesn't the weight of the water in the barrel push a little against the inflow, decreasing water captured? I'm not saying there isn't an advantage, but I don't know what it might be.
- Instead of using a diverter in the downspout, why not just drill a hole in the gutter and connect the hose there, with a screen over the hole? When the barrel is full, the water will just flow over the full hole and go to the downspout. Also, any diverter will decrease the easy flow of water down the downspout, won't it? In a heavy rain, I don't want water to overflow the gutter.
Reply 10 months ago
In very heavy rain some of the water may bypass the barrel because of restrictions in the diverter or hoses but it bypasses in the downspout and exits away from the house. With top filled barrels overflow pipes are often nonexistent or smaller than the in feed so in heavy rain the barrel will overflow. The animated GIF image shows how it is impossible for this design to overflow which is the main advantage. I have been using this setup for a number of years trouble free.
3 years ago
Where did you get your barrels? Round, green barrels are hard to find/come by ...
Reply 3 years ago
These barrels are made in Canada and are quite common in Southern Ontario. I got mine used.
3 years ago
Have 2 55-gallon rain barrels. Have a diverter that can overflow in 3x4 pipe and connected with hose to top of first barrel. Do I want to connect together on bottom or top. For best pressure seems like bottom would be best. Right now have about 8" difference in height...should they be even? One barrel is sealed and one is not - which goes where? Want the best pressure and to fill without overflowing the barrels. Seems to me should be same height (?) with connection on bottom and intake hose positioned slightly lower than top of barrels so only fill that full??? Any help appreciated!!! THANKS!
Reply 3 years ago
Q - Have 2 55-gallon rain barrels. Have a diverter that can
overflow in 3x4 pipe and connected with hose to top of first barrel. Do I want
to connect together on bottom or top. For best pressure seems like bottom would
A – All connections to the barrels should be at the
bottom.The pressure you get from the
barrel increases if you elevate the barrel with a stand.
Q - Right now have about 8" difference in
height...should they be even?
A – The tops of the barrels must be even.
Q - One barrel is sealed and one is not - which goes where?
A – Drill a hole at the top of the sealed barrel to allow
air in and out.
Q - Want the best pressure and to fill without overflowing
the barrels. Seems to me should be same height (?) with connection on bottom
and intake hose positioned slightly lower than top of barrels so only fill that
full??? Any help appreciated!!! THANKS!
A – This system depends on water seeking its own level,
there is no need to connect the rain diverter anywhere but the bottom of the
rain barrel.The weight of the water in
the hose coming from the diverter will push the water into the barrel from the
bottom to maintain level.Once the water
level in the barrel is full it will overflow inside the diverter because the
diverter is beside the barrel not above the barrel.It seems odd but it works very well.
4 years ago
It was time for an upgrade. Same setup but now with a second barrel.
Question 4 years ago on Step 1
Do you have a vent at the top of the rain barrel. Your drawing makes me wonder how the barrel doesn’t get air/vapor locked. To push water in or out you have to let the oposite out. Kind of like holding your finger over the end of a straw then poking it into a liquid
Answer 4 years ago
The top of the barrels is open to the atmosphere, not sealed at all.
6 years ago
I have been using rain barrels for years, the remote placement this system offers is very clever and solves many issues that spout located barrels pose.
Great instructable, thanks!