Collecting rainwater in a rain barrel for use later works great if you install the right system. Typically, they are attached to one of your downspouts and collect the rainwater so it can be used later for things like gardening or cleaning up patios. The water is usually dispensed through a spigot located at the bottom.

There are several different reasons why you might want to collect rain water from your gutters of your home.

If you live in an area of the country that tends to suffer from dry spells through various times of the year, you probably are subjected to outdoor water restrictions which can make gardening very difficult.

Second, if you concerned with lowering your water bill for yourself or simply conserving water for everyone else, there is no better way to do that than collecting rainwater that would otherwise simply wash away in the yard or a sewer drain.

So once you decide you want to create your own rainwater collection system, you have two options: buy a complete system or build your own.

Buy a Complete Rainwater Collection System

DIY Rainwater Collection System: How to Harvest RainwaterThere are commercially available rain barrels that can be purchased at some home improvement stores or ordered online that are a simple solution to get started. Each consist of an entry hole on top of the barrel for the downspout water, and some kind of spigot near the bottom that you can attach a hose and use the force gravity to propel the water through the hose. It will not shoot out in a jet blast but it will do the job for filling a watering bucket or spray nearby gardens or lawns. The only installation that is involved is cutting one of your downspouts with a hacksaw and redirecting the water to your barrel at the correct height.

Most commercial rain barrels cost over $100, but they are designed very well and blend in well with virtually any décor. These units can hold as much as 65 gallons of rainwater.

Some feature diverters that can be attached in the middle of the downspout to allow water to pass through to drain naturally, or be diverted to the rain barrel. Other more advanced version even feature a water pump to generate water pressure to spray further from a hose.

Others feature reversible tops that allow you to convert the top into a flower planter.

If you do decide to purchase a rain barrel with all of the necessary water kit accessories, make sure you chose a round barrel version. The square or rectangular shapes are structurally weaker than the round design and can have issues with splitting in the corners after it has been filled with water several times.

However, if you are looking for function over style and cannot find one to suit your budget, you can make your own at much less cost. All you need are a few materials and a little bit of time.

Kyoto RBSS-75 75-Gallon Rain Barrel, Sandstone-Finish
Amazon Price: $199.99 $194.00 Buy Now
(price as of Nov 8, 2015)

How to Build a Rain Barrel

DIY Rainwater Collection System: How to Harvest RainwaterIf you decide to make your own rain barrel, your major expense will be the plastic barrel itself. You can purchase 55 gallon food grade blue plastic barrels online for $49.99, however, check the local ads such as Craigslist if you are really serious about getting the best deal.

Or you could a 32 gallon or larger rubber trash can with a lid. It will function the same as an enclosed barrel. You will only need to make two cuts using a drill and a hacksaw to any rubber barrel you buy.

First, if you are going to purchase a regular heavy duty rubber trash can, you will need to alter the lid by cutting a small rectangular hole in it with a hacksaw to allow the rain water to be directed into it by the downspout.

Second, you will need to drill ½ inch or ¾ inch size hole at the bottom to allow a spigot to be threaded inside. I would suggest you opt for the ½ thread if possible.

You will need several pieces of materials to finish the job after the cuts. 

  • Downspout diverter
  • Water spigot
  • Teflon tape
  • Plastic mesh material

All three can be purchased for around $25 depending on the quality of the water tap you buy.

Carefully screw the spigot into the hole at the bottom of the barrel. Make sure you keep it straight so it will not leak. Then remove it, and apply Teflon tape around the threads and reinstall the spigot.

Next, mark a rectangle in the top of the barrel (or lid) that is wide enough to allow water from a downspout to enter. Drill two holes in each corner to allow a hacksaw to enter. Then proceed to saw around the outline of the rectangle and remove the plastic.DIY Rainwater Collection System: How to Harvest Rainwater

Place the plastic mesh over the hole and attach by drilling screws with large heads into the barrel (or lid) to hold it in place. This will keep leaves and other debris from falling in the barrel.

Measure the height of the barrel. Next cut several inches above that height on the downspout using a hacksaw. Insert the downspout diverter and place the barrel underneath so that any water will fall smoothly into the opening in the top.

Now all you have to do is attach a water hose and spray to the spigot at the bottom and wait for the rain.

Suncast RB50D 50-Gallon Rain Barrel
Amazon Price: $119.99 $51.65 Buy Now
(price as of Nov 8, 2015)

Is it legal to Collect Rainwater?

Believe it or not, it used to be in several states out west, if it was on Federal land, however, that applied to large scale farming activities. Those regulations have since been relaxed as water and drought becomes more of an issue in the western USA.

For the purpose of the rain hitting the roof of your own home on your own land, it is not illegal to capture rainwater, also called grey water, for later use. Some areas require that you get a permit before installing a

Can you Drink Rain Water?

I wouldn't. After all, it came off your roof shingles which contain a lot of dirt and grim, not to mention they are made from petroleum products and countless other chemicals. That is not what these systems are designed for anyway. Just use the gray water to wash off patios and water garden plants.


If you are handy with tools, creating your own rainwater solutions will not be a problem. There is nothing difficult about the process. You should be able to create your own for anywhere from a third to half the cost of commercially available brands that come with everything needed for the install.

The major expense will be the barrel that collects the rain. However, if you decide to use a heavy duty trash can with lid, those can be had for around $30. Other enclosed barrels will cost more, but deals can be found online on Craigslist

But if all of that is more effort that you want to put forward and you prefer to buy something with a more polished look, it is probably worth it for you to get the kind of all-in-one solution that will suit your needs. They definitely come in handy when you need to water a thirty lawn or garden.

Planter-Urn Rain Barrel - Terra Cotta
Amazon Price: $168.65 Buy Now
(price as of Nov 8, 2015)