How do you collect rainwater and what are the benefits? Whether you have an interest in water conservation or simply want to save a few dollars on your water bill, collecting rainwater for gardening may be the answer for you. Harvesting rainwater with rain barrels conserves potable water — that’s the water that’s safe to drink.
During the summer, much of our potable water is used outdoors. We fill our pools, wash our cars, and water our lawns and gardens. This water must be chemically treated to make it safe for drinking, which is great for you, but not necessarily great for your plants. Collecting rainwater for gardening can eliminate many of these chemical salts and harmful minerals from your soil.
Rainwater is naturally soft. The less water used from your local treatment facility, the fewer chemicals they have to use and the less money they have to spend on those chemicals. There are savings for you, too. Most home gardeners see a rise in their water bill during the summer gardening months and during a drought, many of us have been forced to choose between our garden and our water bill.
Rainwater collection can reduce your bills during the rainy months and help offset your costs during the dry ones. So how do you collect rainwater? The simplest method for harvesting rainwater is with rain barrels.
Using rain barrels involves no special plumbing. They can be purchased, often through local conservation groups or from catalogs or garden centers, or you can make your own. Prices range from around $70 to $300 or more, depending on the design and aesthetics. The price drops considerably if you make your own. Plastic barrels can be painted to blend with your house or landscape.
How do you collect rainwater for use in the garden? On the most basic level, there are five components. First of all, you need a catchment surface, something the water runs off. For the home gardener, that’s your roof. During a 1-inch (2.5 cm) rainfall, 90 square feet (8.5 sq. m.) of roof will shed enough water to fill a 55-gallon (208 L.) drum.
Next, you’ll need a way to direct the flow for rainwater collection. That’s your gutters and downspouts, the same downspouts that direct the water out to your yard or storm sewers.
Now you’ll need a basket filter with a fine screen to keep debris and bugs from your rain barrel, the next component of your rainwater collection system. This barrel should be wide and have a removable lid so it can be cleaned. A 55-gallon (208 L.) drum is perfect.
So now that you’re using rain barrels, how do you get the water to your garden? That’s the last component for collecting rainwater for your garden. You’ll need a spigot installed low on the barrel. An additional spigot can be added higher on the drum for filling watering cans.
Ideally, when using rain barrels, there should also be a method for directing overflow. This can be a hose connected to a second barrel or a piece of drainpipe that leads to the original ground pipe to lead the water away.
Harvesting rainwater with rain barrels is an old idea that has been revived. Our grandparents dipped their water from the barrels at the side of their house to water their vegetable patch. For them, collecting rainwater for gardening was a necessity. For us, it’s a way to conserve both water and energy and to save a few dollars while we do it.
Note: It is important that you safeguard rain barrels by keeping them covered whenever feasible, especially if you have small children or even pets.
In Rainwater Harvesting by Jeremiah Castelo Updated: March 28th, 2021 Published: January 4, 2021 Leave a Comment
R ainwater can be an excellent source of clean water when filtered through the proper channels.
For outdoor uses, simple pre-filtration devices such as mesh screens and downspout diverters are great for removing large debris particles.
For indoor uses such as bathing, cooking, and drinking, one would need a filtration system designed to thoroughly remove harmful contaminants.
This article will discuss the following:
It has been used as an environmentally friendly way of rainwater catchment for use in gardening as well as across landscaping.
Rainwater for gardening collection is a technique that has been widely practiced over the centuries.
In most locations today, you will find that most people build their houses with roof gardens that will absorb the rainwater.
Hence growing a layer of grass. If you don’t have a roof garden though, you can still collect rainwater and use it.
Rainwater collection is always easier with gutters around the roof. But, there are still methods that you can use to collect the water even without gutters. Some of these methods include:
On a rooftop, a catchment area is where there is a certain pathway that water follows. If you have a slanting rooftop, then you already know that all the water is directed downwards.
On the rooftop where two sections meet there will be the formation of a single catchment that will naturally force the rainwater to flow in a stream.
The best thing about these catchment areas is that they focus the water to flow in a certain direction just like the gutters.
This means that, if you look carefully, there will be a section of your house where the rainwater will be falling more heavily than the others.
In that case, you can use a drainage pipe or some collection vessels to collect as well as distribute the water. This is a better way of collecting water than just leaving it to fall at the corners of your house.
Diverters, on the other hand, are some type of metal sections that you can install either on your flower beds or just above your doorways.
They help to prevent these two parts from being hit by frequent rainfall. But you need to understand that diverters and gutters are two different things.
The diverters are just some short pieces of aluminium a few feet long. They are in most cases also fitted underneath the roof shingles hence forming what looks like a metal wall.
The diverters too tend to form concentrated streams of rainwater so you can take advantage of that by channeling the water and collecting it.
This may sound ridiculous to most people, but you can actually use the land itself as a way of channeling and collecting water.
You will do this by looking for the low-level areas in your location where rainwater tends to stagnate or collect when it rains.
Such areas are the best for placing a diverter pipe that can then be used to carry water away to your collection point.
If you don’t have the low-level points in your location, then you can build some natural and slightly depressed valleys as you landscape at the same time. This will help you to carry the water evenly throughout your garden.
Barrels are the most ancient yet the most popular method of water collection.
Rainwater barrels come in different types and you will easily find them in landscaping and gardening centers in your location.
The deal with barrels is that you just stand them in your garden and they collect water as the rain falls.
When using barrels, you don’t need gutters or rooftops to be able to collect water.
In some cases, you will find that the barrels are connected to some underground pipes that direct water to a certain area.
Since there are many styles of barrels that you will find in the market, be sure to find one that fits in the landscaping plan that you are working with. You can also improvise homemade barrels with locally available materials in your home.
Rain Water Barrels
Those who have been practicing rainwater harvesting without a doubt understand how critical it is to have a high-quality barrel. In very many instances, people have bought poorly made barrels that have ended up leaking the water from the bottom.
Image credits: Virginia State Parks staff [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]
⦁ Overflow protection:
During very heavy rainfall, there is a chance that your rainwater barrel may end up collecting more water than you anticipated.
That is why you need an overflow valve to divert as well as regulate all the excess water when the barrel is already filled to the brim.
This overflow valve can either be connected to a storage tank or additional rainwater barrels.
This feature may lack in some barrel designs but most of the modern designs come with an overflow protection valve.
⦁ Mesh Screen Filter:
This is another important feature that should never miss in a good rainwater barrel. This mesh screen helps in keeping leaves, insects, and any other form of debris from entering in the storage section.
At the same time, where there is stagnant water, it is a good breeding place for mosquitoes to lay their eggs.
You may also find some barrels that come with a completely covered top with just an opening that channels water in the barrel.
This is an outlet that helps to dispense water from the rainwater barrel to the outside environment. You can attach a garden hose or even just fill the water into a basin.
A great spigot should be made from brass so that you can prevent rust.
More to that, you should ensure that the spigot is located at the bottom part of the barrel. This makes it easier to empty the contents of the barrel through the help of gravity.
All in all, you may find barrels that come with a threaded bulkhead where the spigot should be attached.
Materials for Making a Rain Barrel
Image Credits: Tsanghexshing [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
Barrels come in a wide range of materials. While the plastic barrels are the best, it is important to know about the rest so that you can be able to make a good selection when buying one.
⦁ Plastic Resin
These are the most common types of barrels and that’s for a good reason. That is because they are easy to clean and very light in weight.
More to that, they are not biodegradable meaning that they cannot break down as a result of bacteria action.
And as much as the plastic resin is UV protected, the rain barrels should be kept out of the sun for longevity.
⦁ Stainless Steel
This type of barrels has a couple more advantages when compared to the plastic ones.
And for that reason, they are used to store a large amount of water for longer periods of time.
You will find them being used as industrial tanks or even cisterns for supplying water in a community.
The stone and clay barrels tend to be smaller as they are very bulky. In most cases, they are only used for decorative purposes rather than for water conservation.
All in all, they can still be used to collect rainwater. However, you must choose a fixed location for the barrel where it won’t be moved as they can be very heavy.
These ones too have been used throughout history for a wide array of purposes.
And that includes collection and storage of water. Wood barrels are very attractive but they tend to be very demanding in terms of maintenance.
That is because wood is biodegradable and it not taken care of it can grow mold and harbor insects as well. It is actually advisable that you invest in treating your wood barrel before using it for harvesting rainwater.
Image Credits: USDA NRCS South Dakota [Public domain]
When it comes to water storage, there are very many myths that surround this a particular topic.
Therefore, in this section, I will give you all the factsabout water storage.
To start with, stored rainwater does notexpire or go bad.
However, it canbecome chemically or biologically contaminated.
The contamination may give the water a certain unusual taste but that’s no expiration.
Actually, the taste can be easily removed by purifying and rotating the water.
This means that, if you have stored water that started out as clean in a cool, dry and dark area, then it can be stored indefinitely.
However, you need to ensure that there are no harmful chemicals nearby, harsh fumes and it is not placed directly on concrete.
All in all, you need to rotate this water from time to time. But that’s just for the sake of your peace of mind.
More to that, when storing your water, you need more than just a filter. A purifier too would do some good.
For instance, chlorine dioxide is a great alternative for killing all types of micro-organisms that dwell in water like parasites and bacteria.
That is why chlorine dioxide is great for treating barrel water before storage or any other water that has been collected from a natural source.
The purifiers alone still cannot remove all the turbidity in the water. That is why it is recommended to use both a filter and a purifier to ensure ultimate cleanliness of your water.
While the collection of rainwater might seem like a normal thing, you will be surprised to learn that it is illegal in some states. The link provides 18 States.
If you live in Colorado especially, you can relate to what I’m talking about.
The water laws in Colorado are so strict that even rainwater collection is virtually prohibited.
That water that patters off on your porch is not yours at all. This makes it very difficult for a regular homeowner to set up any kind of a rainwater harvesting system.
Currently, in the United States of America, there are strict laws and regulation that have been put across nine states in regard to the collection of rainwater.
All in all, the severity of those laws tend to differ in each of the states.
For instance the Colorado Rainwater regulation law passed in 2016 allows homeowners to collect only two barrels.
That is roughly a total of 110 gallons and this should only be on their rooftops. Therefore, before you set up your rainwater barrels, be sure to confirm with the authorities if it is legal to collect rainwater in your state.
As we have seen in the article above. Rainwater for gardening is great for plants and soil health.
Besides being the preferred source of water for plants, it is a healthier option too.
That being the reason, you need to collect, store and keep clean water in order to aid your plant to achieve optimal growing conditions.
All in all, you need to be careful with the storage and collection method you choose.
That is because some like open barrels if left untended to, they can become a breeding ground for mosquitoes.
Also, it is necessary to clean the collection and storage means once in a while to ensure that the water you collect remains clean and fit for use over a long period of time.
Gardening fever gardening for beginners! A beginner friendly site for both the novice and beginner.
Even many experienced gardeners have trouble comprehending just how much water soil can hold. Except in areas with consistently high rainfall, your garden soil’s moisture level will seldom be at “field capacity.” That’s the term scientists use to describe the maximum amount of water a soil can hold. When it rains or when we irrigate, gravity pulls the water down into the soil. After a heavy rain, some of the water may move all the way down to the water table or the bedrock, but a large amount of it is held by capillary forces that cause water to coat each soil particle and partially fill the spaces between particles. (An example of capillary action is the way a paper towel absorbs liquid.) That capillary water is what your crops use as they grow.
Each soil’s field capacity varies depending on how much sand or clay is in it. One cubic inch of coarse sand may contain 125,000 particles, while the same amount of the finest silt could contain 15.6 trillion particles! Soil particles have an astonishing amount of surface area. One cubic inch of an ordinary soil (with a mix of sand, silt and clay particles) could have a surface area of 25 square feet.
What those numbers mean is that many soils can hold 2 to 3 inches of water in each foot of soil depth, and garden soils that contain lots of organic matter can hold even more. Crop roots can reach down 4 feet — sometimes even 8 feet deep — to tap this capillary water. To be sure crops get the water they need, gardeners would ideally want to keep their soil moisture near field capacity to a depth of at least 4 feet. During peak growth, crop transpiration together with surface evaporation can draw as much as a half-inch of water per day. The more water you’ve stored in your soil, the less you will need to provide supplemental irrigation.
To understand how soil moisture levels vary in your area, check out the soil moisture maps from the National Weather Service. These maps will tell you whether soil moisture levels in your region are above or below normal at any particular time.
Here are some non-potable outdoor rainwater collection systems, from the super simple to slightly more complex:
Perhaps the cheapest and easiest way to get started, this uncomplicated setup requires a 32 gallon plastic trash can with lid, a brass faucet with two threaded washers, and a flexible gutter downspout.
Get the tutorial here.
A bit more aesthetically pleasing, this rain barrel how-to includes some extras like adding a mesh screen to the downspout and including a hose attachment to handle any overflow during heavy rains.
Get the tutorial here.
For a discrete rain collection setup, the rain barrel is enclosed within a study, wooden shell.
It’s a two day project that will cost around $150.
Once completed, slap a coat of paint on it to make it blend even more with its environs.
Get the tutorial here.
When you lack a suitable catchment surface, this standalone rain barrel design incorporates a tarp on top to catch the rain, similar to an inverted umbrella.
Get the tutorial here.
In this DIY, a series of PVC pipes are used to connect two or more rain barrels, with overflow piping and garden hose attachment for irrigation.
Since the pipes are drilled into the underside of the barrels, and the barrels sit atop a wooden stand, most of them are neatly hidden from sight.
Get the tutorial here.
Using a recycled intermediate bulk container (or IBC), this project increases rain collection volume to 275 gallons, all in one container.
Watch the accompanying videos to see how it’s done, as well as the final update where they added two more IBCs in an enclosure that helps the setup blend into the building.
Get the tutorial here.
When you would prefer to build “up” rather than “out”, this system situates the rain barrels so they lay horizontally, allowing them to be stacked on top of each other, supported with a wooden frame.
Get the tutorial here.
Best for large gardens that have a high water demand, this 2,500 gallon set up is located next to the barn and includes extras like a water pump, overflow system, and first flow diverter that flushes the first few gallons of collected rain to prevent dust and dirt from accumulating in the cistern.