High Volume Rain Barrel

Step 4 Connecting the barrels to the downspout

We had a leftover downspout diverter from the Fiskars Rain Barrel http://www.rain-barrel.com/tuscanyspicegranite.html that we installed at the front door. I used this to supply water to the barrels.

If you choose to use a downspout diverter, there are a number of models available on the internet which connect in different ways. While purchasing one will add approximately $30 to the cost of your project, it will also allow you to use your existing downspout system for handling the rainwater when the barrels are full. See http://www.rain-barrel.com/how_it_works.html for a video explanation of how they work in general.

The most common way for filling the barrels is to cut a hole at the top and install a screen over it to keep out debris and mosquitos. As stated above you must also plan for run-off once the barrel is full. As I already had the spare downspout diverter, it allowed me be create a completely contained system. The only holes drilled into the barrels are a series of 5/32" (smallest drillbit I had with me) holes in the top of the barrels to balance the air pressure in the barrels as they fill and empty.

These are the parts I used for connecting the barrels to the downspout, all from my local Ace Hardware:
1 3/4" MIP to 5/8" barb adapter
4' of 5/8" ID (internal diameter) clear tubing
**This hose fit into the opening of the downspout diverter and also allowed for a larger volume of water to enter the barrels at one time.

Installation:
1. I used a 3/4" spade bit to drill out the bottom of the one of the internal threaded bung plugs, being careful not to damage the threads.

2. I screwed the bung plug back into the barrel so as to use my homemade wrench to ensure it was tight.

3. I screwed the 3/4" MIP to 5/8" barb adapter into the threads of the bung plug.

4. I attached the tubing to the barb and secured it with a clamp.

5. I followed the instructions with diverter to install it into the downspout and then connected the clear tubing to it.

Comments

[Eric T]

If you thredd a steel pipe niple into those bung plugs "caps". The plastic plug breaks out. No drilling is required. = Less chance for blood :)

[nuttman]

From the picture, it looks like the rain diverter is slightly below the top of the barrels. Is this correct? With the holes for balancing air pressure, I would think the diverter must be below these; Water overflow would come out the top of the barrel through the holes, rather than backing up the diverter. I've been thinking about taking 1/2" PVC pipe and making a "periscope" out of the tops of the barrels for balancing air pressure. The diverter could be mounted slightly higher than the top of the barrel, and the periscope would extend above the diverter. Any thoughts on this? Do you have water come out of the top holes when the barrels fill completely?

[thebigbarn]

It can be a little deceiving. Inside the diverter is the overflow lip. The port for the tubing to connect to is below that. Therefore it appears as though it were lower when it is not really. It is balanced so that I have the barrels almost completely full. I have not had water come out of the air holes on the top. I'm sure the 1/2" PVC periscope would do the job for balancing the air pressure, but I think it is more than you need. The 8-12 5/32" drilled holes are working fine for regulating air pressure when filling and emptying the barrels. If you proceed using that design, you should make sure that you have a screen on the PVC to make sure that you're keeping out mosquitoes and other "undesirables".

[nuttman]

Screening is a must! Anyway, my point was that anyone using a diverter such as this (mine is a RainReserve) must be aware of the mounting level in relation to the top of the barrel. Too high, and water will want to overflow through the top of the barrel rather than back up the tube to the diverter as intended. (In a heavy rain, I'll bet the pressure of the water trying to get out through the little holes may still back up to the diverter.) The vent pipe idea (or "periscope") simply allows for some leeway in the mounting height of the diverter. As long as the end of the vent pipe is above the overflow mouth of the diverter, there should be no problem. It's all about water seeking its own level. I think this is what's great about these projects. There's so many ways people can customize them. Thanks for all the great information and details you provided about yours!

[wingrider78]

Hey there...how many of those 5/32" holes did you have to drill to allow the barrels to fill and empty smoothly??  I have purchased a diverter and am just waiting for it to come now so I can build the system in your instructable...I can't wait :)

[thebigbarn]

From memory, I think 8-12.  You can test by drilling some holes and then letting out some water into a watering can.  If you can hear air being sucked in through the holes after you have closed the valves, then you need more holes.

[qman007]

Is there any reason you didn't use a 3/4" drill bit and use the existing threads that were in the cap?

[thebigbarn]

I don't understand your question.  Instructions 1 & 3 in this step outline doing just what you asked.