5 Important Benefits Of Rainwater Harvesting

Collecting rainwater can help solve the water scarcity if you are not connected to the utility water system.

When living off the grid, you will be relying on water sources such as boreholes, rivers, and lakes if you live near such water bodies. However, these might be inconvenient in some cases.

Rainwater harvesting is a sustainable water management practice that everyone can implement. All you need are the water storage containers and use the most appropriate method to collect water.

The water storage containers should be sized according to your household water requirements.

In this post, we will highlight the benefits of rainwater harvesting, how to do it, and discuss rainwater collection systems.

We will also walk you through the steps of filtering, treating, and storing rainwater. Keep reading so you do not miss out on anything!

5 Benefits Of Rainwater Harvesting

5 Benefits Of Rainwater Harvesting

Rainwater harvesting or rainwater collection has many benefits to different households. It is the solution to water scarcity problems, and it also helps control water-borne diseases and revitalize groundwater.

With enough water from the rains, you can grow crops and water your animals all year round.

For many years, people have preferred rainwater for drinking to other sources of water. Whether you need water for laundry or other household uses, rainwater is the best option.

Collecting enough rainwater for your off-grid lifestyle comes with the following benefits:

Solve The Scarcity Of Water

Water can be scarce during dry seasons when boreholes and small streams dry up. That forces people to walk long distances, searching for water for drinking, cooking, and other household uses.

You can solve this problem by collecting enough rainwater during the rainy season for future use.

Serving The Needs Of Drinking Water And Daily Life

Rainwater is classified as soft water. It is free from minerals that do not lather with soap and other detergents.

In many cases, you only need to filter and treat it. You can drink the treated rainwater and also use it for laundry and other things around your home.

Grow Plants And Livestock

As an off-gridder, you need to have a vegetable garden and keep livestock. That might not be possible without water.

Rainwater is ideal for irrigating your crops and watering your animals even in the dry season. You can grow vegetables all year round if you collect enough rainwater, giving you a constant fresh food supply.

Prevent Water-Borne Diseases

Boreholes, streams, and lakes are the alternative water sources, but they are prone to water-borne diseases. When living off the grid, diseases are the last thing you want to hear.

Treated rainwater helps you control or prevent water-borne diseases, thereby keeping your family healthy.

Revitalize The Groundwater Level

An increase in water demand has made people resort to underground water to meet their daily needs.

This has led to the depletion of groundwater. Rainwater collection means less demand for underground water, thereby improving its quantity and quality.

5 Steps To Use Rainwater

5 Steps To Use Rainwater

To use rainwater, first, check the local regulations. Once done, determine the amount of water to meet your needs and use an appropriate rainwater harvester to collect just that.

You might need to learn how the chosen method works. The last steps are filtration and treatment, after which the water is ready for use.

Many people make mistakes by not following the steps of collecting safe rainwater for drinking and general use. Let that not be you. Follow these steps:

Step 1: Check Local Regulations And Guidance

There might be local laws and regulations that govern how rainwater should be collected in your area.

Check them out and ensure that the water harvesting method you will be using is permitted to avoid clashing with the authorities.

Step 2. Determine The Amount Of Water Will Need

For families, we have a table on how many gallons for a single family. On average, each person uses about 37 gallons of water daily. The daily water requirements by different households are outlined in the table below.

Size of HouseholdGallons Needed
3 People111
5 People185
7 People259
The daily water requirements by different households

About 70% of total daily water usage is for indoor use. Outdoor water usage stands at about 30%, but it can be higher in dryer areas and homes with water-intensive landscapes.

Please note that your daily water consumption can significantly increase if you use it for irrigation or watering livestock.

Step 3. Learn How A Water Harvester Works

There are different types of rainwater harvesters. You should learn about them and choose the one that meets your needs or is reliable in your area. More on rainwater collection systems in the next section.

53 Gallon Portable Rain Barrel Water Tank

Step 4: Water Filtration And Treatment

Rainwater only needs to be filtered and treated to make it safe for drinking and other uses. You do not need to worry about water softening because rainwater is classified as soft with zero hardness.

Check the section on how to filter rainwater for more information.

Filtering removes any suspended particles such as plant materials. Treating, on the other hand, kills water-borne disease-causing organisms. This makes water safe for both human and livestock use.

Step 5: Test & Give It First Drink

Once rainwater is filtered and treated, it is ready for drinking. Enjoy the taste of rainwater and remain healthy.

4 Different Systems To Collect Rainwater

4 Different Systems To Collect Rainwater

There are four commonly used rainwater collection systems. You can choose to use a rain barrel, rooftop rainwater, rainwater harvesting through solar panels, and using water cisterns.

The system you choose depends on your budget, location, and the type of house you have. Generally, your living conditions and intended use of water will influence your choice.

Rain Barrel

Rain barrels are containers used for collecting and holding rainwater from the roof. This water can be later used outdoors or indoors.

The size or number of rain barrels you need depends on the household water requirement. The more people you have in your family, the more water you need.

Rain barrels vary in price depending on the material used in making the barrel and barrel capacity. You can expect to pay between $70 and $300 for a single container. If buying many of these containers, then the seller can/may give you a discount.

Surface Runoff Harvesting/Rooftop Rainwater Harvesting

Rooftop rainwater harvesting involves using gutters and downspouts to channel water from the roof into a storage container.

The water storage container can be a rain barrel or water tank. The entire system is called a water catchment system.

On average, you might pay $2,500 for a rooftop rainwater harvesting system.

An extensive water catchment system can cost you more than $21,000 if you need high-capacity tanks and a water disinfection system also attached to it.

Rooftop water harvesting is the commonly used method because of its high efficiency. It also helps in reducing surface runoffs on your property.

That will help you control soil erosion and avoid dampness around your home.

Rainwater Harvesting Through Solar Panels

This method is feasible if you already have a solar panel array to power your off-grid home. Apart from harnessing solar energy, you can also use photovoltaic panels for collecting rainwater.

PV panels are glass-clad, meaning they offer you the best surface for collecting rainwater. The water collected is safe enough for use in laundry, irrigation, flushing toilets, among others.

Like rooftop rainwater harvesting, you will also need water barrels or water cisterns to store the collected water for future use. That means you will have a higher upfront cost if you do not have the solar panels on your rooftop.

The average cost of solar panels is $2.72/W. For a 5kW system, you might pay a total of $13,600 for the solar panels and installation charges of between $11,560 to $15,640.

In total, it will cost you between $25,000 to $30,000 to buy and install a solar system of that capacity. You can then factor in the cost of water storage containers.

Water Cisterns

Water Cisterns

Water cisterns are water storage containers that can be above the ground or buried underground. Their market prices are almost the same as the prices of water barrels.

Water cisterns are priced between $0.50 and $4.00 per gallon. An above-the-ground 1,000-gallon galvanized steel can cost about $2,000.

And underground, 5,500-gallon concrete water cistern price ranges from $17,000 to $21,000 to install. The cost is high because of the excavation involved.

If operating on a tight budget, then you should opt for above-the-ground water cisterns. They will cost you between $70 and $250 to install, much like the water barrels.

Water cisterns offer a long-lasting solution to rainwater harvesting. They are efficient and convenient. However, the upfront cost is high.  

FCMP Outdoor Wood Grain Rain Barrel

How To Filter The Rainwater?

Water filtering and treatment make it safe for drinking, thereby promoting good health. Apart from the contaminants and disease-causing organisms removed from water, the process can also improve the water taste.

Good-tasting water is enjoyable to drink and quenches thirst more effectively.

Boil The Water

Water boiling helps to remove temporary water hardness and kills germs. It is the traditional method of water treatment still in use in many homes.

If you do not want chemicals such as chlorine bleach, then boil your water to a temperature of about 100 degrees Celsius (212 degrees Fahrenheit).

Disinfect The Water With Chlorine Bleach

Chlorine bleach is the modern alternative to boiling water. To save on fuel used for boiling water, you can buy this chemical and use it to get rid of germs in the water.

The collected rainwater will be clean and pure after the process.

The table below gives you details of the number of chlorine bleach drops you need for a given quantity of water.

You might be forced to double this if water is physically cloudy or colored. Once the chlorine bleach is added to water, stir thoroughly to mix and let the water settle for 30 minutes before use.

Volume of WaterAmount of 6% Bleach to Add*Amount of 8.25% Bleach to Add*
1 quart/liter2 drops2 drops
1 gallon8 drops6 drops
2 gallons16 drops (1/4 tsp)12 drops (1/8 teaspoon)
4 gallons1/3 teaspoon1/4 teaspoon
8 gallons2/3 teaspoon1/2 teaspoon
Volume of Water and Amount of Bleach to add

Run The Water Through An Activated Carbon Filter

The activated carbon filtration method removes unwanted tastes, odors, micropollutants, chlorine, radon, fluorine, and other elements from water. This method uses the adsorption property of the contaminants.

The efficiency of the activated carbon filtration method depends on the water composition, operating parameters, and the nature of activated carbon used. Learn more about activated carbon filtration.

Ultraviolet Light

Ultraviolet light is used for killing disease-causing organisms in the water. The method involves passing rainwater through chambers and systems that remove organic matter.

The ultraviolet light then destroys the genetic material of microorganisms, preventing them from multiplying.

There are also DIY water filter systems for off-grid living. You can explore each of them to identify the one you can implement in filtering rainwater.

How Long And How Can You Store Rainwater?

Rainwater has an indefinite shelf-life. However, you need to properly store it away from algae and mosquitoes using the appropriate water storage containers.

The recommended materials for water storage containers include concrete, fiberglass, metal, and plastic.

How do you stop algae and mosquitoes from ruining your water? Algae does not grow in darkness.

So, they are easy to eliminate by limiting the amount of light entering your water storage container. Alternatively, you can bury it underground.

A backyard water storage container can become a breeding ground for mosquitoes. Apart from transmitting malaria, you do not want to have them in your water.

Sprinkle a tablespoonful of oil on your water in the tank if you are draining from the bottom. The oil floats on the surface to cover your water and will not be in the portion you are using.

If you are planning to store rainwater for long, you should filter and purify it before storage. That ensures you destroy any microbial life in it. You then put the filtered and purified water in a sterilized container.

Fun Facts

Drinking Rainwater

It’s the rainy season where I live. My father loves to drink rainwater. I’m not like that.

But “Sir” and I have one thing in common: we like to use rainwater to make tea. Told you that using boiled rainwater to make tea will bring a very delicious taste!

Our rainwater collection system is simple. It is the collection of rainwater from the gutter. We never collect water from early bouts of the season.

You know, the rainwater was not clean at that time. The trick here is, collect rainwater in the middle of the season. Clean and fresh.

Do not mix rainwater and other water sources you have

FAQs

Is collecting rainwater safe to drink?

Rainwater can be contaminated by suspended elements in the air, including industrial emissions. It is not safe for drinking unless you filter and purify it using the recommended methods.

Which states is it illegal to collect rainwater?

In most of the states, homeowners are not regulated on rainwater harvesting. The only states with strict laws regarding rainwater collection are Colorado and Utah.

How do you clean rainwater for drinking at home?

Rainwater filtration and treatment methods vary depending on your finances. Some are expensive to install but are the most efficient. You can use UV filters, active carbon filters, chlorine bleach, or simply boil the water.

Can you purify rainwater?

Yes. Rainwater can be purified or filtered for drinking and other domestic use. All you need is a clean catchment surface such as rooftops to collect the water from. Water purification simply means making it safe for human consumption. You can do that by using ultraviolet filters or any other system.

How do you sanitize rainwater?

Rainwater sanitization is the same as water purification. The goal is to eliminate disease-causing microorganisms from your water. Chlorination, ultraviolet light irradiation, and heat treatment are the commonly used methods you can try.

Is rainwater clean or dirty?

Rainwater can be clean or dirty, depending on the collection method. Buildings, trees, containers, and elements in the air all determine the state of rainwater. Even visibly clean water is not pure and should not be used for drinking.

Do I need to filter rainwater?

Yes. You need to filter rainwater if intending to drink it or use it for cooking. On the other hand, you do not have to do it for domestic and outdoor use. You might also need to filter rainwater for watering animals.

Wrapping Up

Harvesting enough rainwater for your family will help you solve the water scarcity problem.

You only need to choose the appropriate method or system of collecting it before it disappears underground. However, you should always filter and purify rainwater.

We are grateful for stopping by to read this article at the Em Offgrid. We hope you found the information useful in solving your problem. You can also view our other posts on off-grid survival tips and other related topics.