Backyard Rain Harvesting Project

Capturing the rain is a great way to save water and irrigate your garden. If you already have rain barrels, just follow these simple steps and you’ll be ready for the next downpour.

By Fred Wulff

Harvesting rain water is a great way to help conserve water. And, for me, it was another step toward making my dream of a permaculture backyard. The barrels for my rain harvesting system were purchased through SAWS and they were a great choice because they came with all the required fittings and attachments as well as a screened lid.

This project can be completed in less than a day if you have all your materials ready. I wanted to have my rain barrels elevated enough so I could store hoses or other hose attachments together. I also diverted my downspout away from the corner of the house.

Tool List

– Shovel

– Saw (circular or hand)

– Hammer

– Screwdriver (electric preferred)

– Level

– Utility Knife

– Hack Saw (for cutting the gutter)

– Pop rivet tool (securing gutter)

– Safety Equipment (glasses, gloves, closed toe shoes)

Material List

– SAWS Rain Barrels, 2 ea

– Cinder Blocks, 8″x8″x16″, 10 ea

– Pressure Treated 2″x4″x8′, 8 ea

– Wood Stakes 1″x2″x2′, 5 ea min.

– Nails, 16 Penny 3.5″

– Deck Screws, 3″

– Weed Blocker Material, porous

– Gravel, 2ea 5 gal buckets

– Pop rivets or sheet metal screws

– Downspout elbow


1.Design: I knew I wanted my barrels to be side by side so one would overflow into the other. I began by choosing a site with a downspout from the roof, then measuring my barrels and building the deck to know how much of an area I would need to prepare for the placement of the system.

2. Decking: Keep in mind, once filled with rain water, each barrel could weigh about 417 pounds. I built the decking to support and distribute the weight accordingly. The drawing below is the plan I used to build the deck. Note the center support beam that will rest on the center cider blocks during installation. The frame is attached with 16 penny nails. The decking is attached with deck screws.

3. Site prep: Choose an area with an existing downspout and, if needed, remove the downspout. Make sure the site for the barrel is level. Measure out the area and remove the grass. Level the dirt as best as you can by eye. Then, using a left over 2″x4″ with a level on top, I added or removed excess dirt to ensure the site was level from front to back and side to side. Make sure the dirt is packed down hard once the leveling is complete and check for level again.

4. Support structure: Cut and place weed blocking material into the prepared site. Lay out the cinder blocks to support the decking. I opted for two blocks high to have room for storage. After the blocks are properly spaced and placed, drive the wood stakes (rebar or other stakes could be used) into the ground inside the openings to help keep the blocks in place. I used a left over cedar fencing board (not listed in materials) in front as an edge stop. Pour gravel between blocks and spread evenly.

5. Decking installation: The decking is placed on top of the cinder blocks. Ensure the decking is not touching the house and is equally spaced. The center beam and sides should rest firmly on the cinder blocks. Check for level again.

6. Barrel installation: Prepare the barrels by installing the spigots. Place barrels on the decking so that one of the barrels will be aligned with the downspout. Next, connect the two barrel overflow ports with one of the accompanying hoses. Use the utility knife to cut excess hose. Connect one end of the hose and attach the metal clamp to secure it to the overflow port and tighten the clamp. Slide on the other clamp and connect the other end of the hose to the second barrel, then tighten the clamp. Cap off one of the other end overflow ports and attach the second hose to the remaining overflow port.

7. Downspout reinstall: After the barrels are installed, measure the length of downspout you need. Cut with the hacksaw and reinstall your gutter using rivets or sheet metal screws. I finished off the install with a downspout elbow that let me direct the water straight down into the barrel. Home improvement stores also sell flexible downspout attachments you could use.

This has been a great project. I’m already using the rainwater collected for my garden and plants!

Fred Wulff is a former middle school science teacher for Northside Independent School District.

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Our Guest Authors are fantastic former SAWS employees, incredible interns and community leaders in the local landscaping world. They are all as passionate as we are about saving water with beautiful, diverse landscapes.
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