Rainwater Harvesting Barrels: A Comprehensive Guide

One of the most accessible methods is rainwater harvesting, and at the center of this practice is the rainwater harvesting barrel. This essential tool can save water, reduce utility bills, and support sustainable landscaping practices.

This comprehensive article will explore what rainwater harvesting barrels are, their benefits and types, how to use them, and what to consider before buying one. A comparison table is included to help you find the best option based on your needs.

What is a Rainwater Harvesting Barrel?

A rainwater harvesting barrel, commonly known as a rain barrel, is a specially designed container used to collect and store rainwater that flows off rooftops through the building’s gutter system and downspouts. Instead of allowing this water to run off into the storm drains—often carrying debris, pollutants, or causing erosion—it is diverted into a barrel where it can be stored for later use. Typical applications include watering gardens and lawns, cleaning outdoor surfaces or tools, washing vehicles, and, in more sophisticated systems, flushing toilets or supplying greywater systems within homes.

Rain barrels are available in various shapes, sizes, and materials, each suited to different preferences and environments. The most popular options are plastic barrels, which are lightweight, affordable, and corrosion-resistant. Wooden barrels, often repurposed from whiskey or wine casks, provide a rustic, aesthetic appeal but require more maintenance to prevent leaks and rot. While less common, metal barrels are incredibly durable but may require coatings to prevent rust, especially outdoors in wet climates.

To ensure functionality and safety, rain barrels typically include several vital components. A spigot or hose bib is installed near the bottom of the barrel, allowing users to easily access the stored water for watering cans or garden hoses. An overflow valve or outlet is positioned near the top of the barrel to manage excess water when the barrel reaches capacity—this prevents flooding near the home’s foundation. Most barrels are also fitted with a mesh screen or filter at the intake point, which serves two primary purposes: keeping leaves, twigs, and debris from entering the water supply, and preventing mosquitoes and insects from breeding in the stagnant water.

Overall, a rainwater harvesting barrel is a simple yet effective tool for anyone looking to reduce their environmental footprint, lower their water bills, and take advantage of a natural, renewable water source right in their backyard.

Why Use a Rainwater Harvesting Barrel?

The benefits of using rainwater harvesting barrels are both ecological and economic:

Environmental Benefits

Water Conservation: Reduces dependence on municipal or potable water for outdoor use.
Stormwater Management: Decreases the amount of stormwater runoff, which can carry pollutants into local waterways.
Drought Resilience: Provides a backup source of water during dry periods.

Economic Benefits

Lower Water Bills: Using rainwater for irrigation can significantly reduce utility costs.
Incentives: Most regions offer rebates or incentives for installing rain barrels.

Garden and Landscape Benefits

Chlorine-Free Water: Rainwater is free of salts, minerals, and chemicals, making it better for plants.
Soil Health: Soft water reduces soil compaction and helps maintain healthy soil biology.

Types of Rainwater Harvesting Barrels

Choosing the right rain barrel depends on location, usage, and preferences. Below is a breakdown of the most common types:

Plastic Barrels

These are the most widely available and affordable.

Wooden Barrels

Often made from repurposed whiskey or wine barrels, these provide a rustic aesthetic but require more maintenance.

Collapsible Barrels

Ideal for seasonal use, these are made from heavy-duty fabric and can be folded away when not in use.

Decorative Barrels

These barrels are designed to blend in with landscaping, often mimicking urns or stone textures, while functioning just like standard barrels.

Modular Systems

These consist of several interlinked barrels or tanks that expand your collection capacity and are suitable for larger gardens or homes.

Key Features to Consider

When selecting a rainwater harvesting barrel, look for the following:

Feature	Description
Capacity	Ranges from 40 to 100+ gallons. Choose based on roof size and water needs.
Material	Plastic is the most common; wood is aesthetic but requires more maintenance.
Screen Filter	Prevents leaves and mosquitoes from entering.
Overflow Valve	Helps redirect excess water when the barrel is full.
Spigot or Hose Bib	To access stored water, check for hose compatibility.
Linking Kit	Allows multiple barrels to be connected for more capacity.
UV Protection	Prevents algae growth inside the barrel.

Installation and Maintenance

Installation Steps

Choose a Location: Ideally, under a downspout and near the water’s edge.
Level the Ground: Place the barrel on a firm, level surface; a stand may be required.
Attach Downspout Diverter: Cut and modify your downspout to direct water into the barrel.
Secure Barrel: Ensure it is stable, especially when full.
Connect Overflow Valve: Set up an overflow hose or pipe to redirect excess water away from foundations.

Maintenance Tips

Clean Gutters Regularly: Prevents clogging and ensures cleaner water.
Inspect the Screen: Check for tears or blockages to remove insects and debris.
Drain in Winter: Avoid freezing damage by emptying the barrel before cold weather.
Clean Barrel Seasonally: Remove sediment buildup with a vinegar or bleach solution.

Use Cases for Collected Rainwater

Rainwater collected in barrels should not be consumed unless properly filtered and treated. However, it has many practical uses:

Irrigation: Water your lawn, garden, and potted plants.
Cleaning: Wash garden tools, bikes, or outdoor furniture.
Refilling Ponds or Birdbaths: Provides a chemical-free water source for wildlife.
Flushing Toilets: In homes with greywater plumbing systems.

Legal Considerations

In most areas, collecting rainwater is legal and even encouraged. However, some regions have regulations regarding:

Storage Capacity Limits
Water Usage Restrictions
Permit Requirements

Always check with your local municipality or water authority to ensure compliance.

Comparing Popular Rainwater Harvesting Barrels

Here is a comparison table featuring popular rain barrels based on capacity, material, price range, and notable features:

Model	Capacity	Material	Price Range	Notable Features
Good Ideas Rain Wizard 50	50 gal	BPA-free polyethylene	$90 – $130	Rustic look, brass spigot, UV resistant
FCMP Outdoor RC4000	45 gal	Recycled plastic	$80 – $110	Dual overflow ports, flat-back design
Enviro World Rain Barrel	55 gal	HDPE Plastic	$85 – $120	Child-proof lid, screen guard, overflow hose
RTS Home Accents Barrel	50 gal	Molded plastic	$100 – $150	Wood grain texture, durable spigot
Algreen Castilla	50 gal	Resin	$120 – $180	Decorative urn design includes a diverter
Vingli Collapsible Barrel	66 gal	PVC Fabric	$40 – $60	Foldable, portable, large capacity

DIY Rain Barrel Systems

Building a do-it-yourself (DIY) rain barrel can be a cost-effective and gratifying experience for individuals who enjoy hands-on home improvement and sustainability projects. It also promotes reuse and recycling, especially if you can repurpose materials you own or obtain for free.

Supplies Needed

The most basic components for a functional DIY rain barrel include:

Item	Purpose
Food-grade plastic drum (50–60 gallons)	Acts as the main water storage container. Must be safe and free from toxic residues.
Faucet or spigot	Allows easy access to the stored rainwater.
Inlet screen or mesh	Prevents leaves, twigs, and insects from entering the barrel.
Overflow pipe or hose	Directs excess water away from the house when the barrel is full.
Drill and sealant	Used to create holes for fittings and seal any gaps or joints.

You may also want optional items like a stand or elevated platform to improve water pressure when using a hose and to make accessing the spigot more convenient.

Step-by-Step Guide to Building Your Rain Barrel

Once you have all your supplies on hand, follow these simple steps to construct and install your DIY rainwater harvesting barrel:

Prepare the Barrel
- Clean your plastic drum thoroughly, especially if it previously contained any liquids, even food-safe products. Rinse it with warm, soapy water and let it dry completely.
Install the Spigot
- This ensures you can draw water while leaving some sediment undisturbed at the bottom.
- Fit your spigot into the hole using a watertight sealant or rubber washer. You may need a threaded bulkhead fitting for extra durability and leak prevention.
Create the Inlet
- Cut a large opening or circular hole in the top of the barrel where your downspout will direct rainwater.
- Cover this opening with a fine mesh screen, securing it tightly to prevent mosquitoes, insects, and large debris from entering. You can use a bungee cord or weather-resistant tape, or construct a wooden frame for a cleaner look.
Add the Overflow Mechanism
- Drill a hole a few inches below the top edge of the barrel and insert an overflow pipe or hose. This ensures that excess water is directed away from your home’s foundation once the barrel fills up, preventing flooding or erosion.
- The overflow outlet can be connected to a second barrel, rain garden, or directed downhill into your yard.
Set Up Your Rain Barrel
- Choose a level location near the downspout. It’s best to place the barrel on a raised platform made from concrete blocks, bricks, or a custom wooden stand. This improves water pressure for hose use and makes the spigot more accessible.
- Redirect your downspout to flow directly into the mesh-covered inlet on top of the barrel. This may require cutting the downspout and using an elbow joint to guide the flow.
Test for Leaks and Functionality
- Fill the barrel partially with water and check all connections for leaks. Tighten fittings or apply additional sealant as needed.
- Once everything is secure and functioning, you can start collecting rainwater.

Cost Considerations and Benefits

DIY rain barrels can be significantly less expensive than commercially available models. Depending on features and design, a store-bought barrel with all the fittings might range from $80 to $200. In contrast, a DIY version could cost as little as $15 to $40, primarily if you can source a used food-grade drum from local businesses such as bakeries, food distributors, or car washes (often for free or at a very low cost).

Beyond the financial savings, building your rain barrel also allows you to personalize the aesthetics. You can paint the barrel, decorate it to match your garden, or camouflage it with landscaping features. Plus, the satisfaction of creating a sustainable solution from scratch adds another layer of reward to the project.

In short, a DIY rain barrel is a simple and accessible way for homeowners to embrace eco-friendly practices, conserve water, and gain independence from municipal water supplies for outdoor use.

Pros and Cons of Using Rain Barrels

Understanding the advantages and disadvantages helps you decide if a rain barrel system is right for you.

Pros

Low-cost and simple to install
Reduces utility bills
Promotes sustainability
Improves garden health
Minimizes runoff

Cons

Limited capacity
Requires maintenance
Risk of algae or mosquito growth
Water may freeze in cold climates
Non-potable unless treated

Expanding Your System

If you find that one barrel isn’t enough, you can easily upgrade:

Add More Barrels: Link multiple units together.
Install a Pump: For better water pressure when using hoses or irrigation.
Integrate with Irrigation Systems: Drip irrigation can be connected directly to rain barrels with proper planning.

Final Thoughts

Rainwater harvesting barrels offer a practical, affordable, and eco-friendly solution to many common water challenges. Whether you’re a homeowner, gardener, or simply environmentally conscious, installing a rain barrel can help you make the most of every drop of water on your roof. Take the first step today, and start harnessing the power of rain—nature’s free water source.