Rainwater Harvesting: Using Rain Barrels for Drip Irrigation

Rainwater Harvesting: Using Rain Barrels for Drip Irrigation

Nov 2nd 2023

The rain has filled your barrels, so what do you do now? Rainwater irrigation is fantastic because it conserves resources and is great for the environment. The Rainwater is pure, whereas other water sources may contain chemicals and salts. The pH of Rainwater is ideal, and it delivers nitrates to soils and plants in the right amounts. So, how do you transport the water from your full rain barrels to your parched garden?

The stored water can be distributed using gravity if the system is set up correctly. When it comes to water usage, drip irrigation is the most effective method. It is the most energy-efficient when gravity is used for distribution.

Benefits of Using Rain Barrel Water for Garden Beds

  • Using rainwater reduces the dependency on conventional water supplies, leading to significant savings in water bills.
  • Rainwater harvesting reduces runoff, thereby minimizing soil erosion and flooding. It also decreases the demand for municipal water supply, reducing the energy used for water treatment and distribution.
  • Rainwater is free from chlorine and other chemicals present in tap water, making it more beneficial for garden beds.

Rainwater Harvesters Is a Sustainable Water Solution

Rainwater harvesting is an age-old practice dating back thousands of years. The primary aim is to collect, store, and use rainwater that falls onto roofs or other catchment areas. This technique becomes more relevant today as water becomes scarcer.

Rainwater harvesters usually comprise catchment areas like roofs gutters to direct the flow of water, filters to remove debris, and storage systems like cisterns or rain barrels. The stored water can be used for various purposes, from flushing toilets to watering plants. However, an exciting and sustainable use of this harvested water is for irrigation systems, specifically drip irrigation systems.

Drip Irrigation Systems

Traditional irrigation systems like sprinklers are notorious for wasting water. They distribute water over a broad area, much of which evaporates before reaching the roots of plants or simply runs off. This is where drip irrigation systems come to the rescue.

Drip irrigation uses a network of tubes, pipes, and valves to drip water slowly, ensuring minimal wastage and maximum utility. Two popular components used in these systems are the drip emitter, soaker hoses and 1/4" soaker driplines. While drip emitters release water at specific points to individual plants, soaker driplines allow water to ooze along their length, ensuring an even distribution of water to a row of plants. For a more precise watering use 1/4" soaker dripline. Unlike soaker hoses, these driplines have emitters built in at designated spacing's and provide water where it is needed.

For those interested in the soaker driplines, you can find a variety of options, including the 1/4" soaker dripline, at this link.

Combining Rain Barrels and Drip Irrigation

The use of a rain barrel is one of the most common ways households store harvested rainwater. These barrels provide an immediate water supply that can be directly integrated with drip irrigation systems.

Pressurized Water Requirement

For effective operation, drip systems require pressurized water. While conventional water sources offer this pressure naturally, rain barrels do not. Therefore, the use of a pump becomes essential. Installing a pump will ensure the water from the rain barrel is pressurized sufficiently to flow through the drip system efficiently. You can create pressure by elevating your tank, most drip irrigation systems require a minimum pressure of 15 psi.

Implementing a Pressure Regulator

Given that pumps can sometimes over-pressurize the water, it's crucial to use a pressure regulator. This device ensures that the water's pressure remains within the required limits for the drip system to function correctly, protecting the drip emitter and 1/4" soaker driplines from potential damage.

Connecting the Rain Barrel to Drip Systems

Once pressurized, the water can easily flow from the rain barrel through a hose or pipe connected to the drip system. Filters should be installed at the barrel's outlet to prevent any debris from entering and potentially clogging the drip system.

Maintaining the System

Routine maintenance is essential to ensure the smooth operation of the integrated system. Regularly check the rain barrel for any sediment buildup and clean it as needed. Additionally, inspect the drip systems for any blockages or leaks.

A DIY Guide to Drip Irrigation

Those who have recognized the benefits of rainwater harvesters will likely find the concept of combining rainwater harvesters with effective irrigation systems intriguing. With the help of a rain barrel, you can ensure that your flower beds are always well-watered thanks to its efficient design. The results can be magnificent when used in conjunction with soaker driplines or other drip systems.

Setting Up the System

The set-up process is simple, but knowing how much pressure you have available is important.  If you have less than 10 psi available, you will be limited by the type of driplines or emitters you can use and how big of an area you can water. Using manual valves and smaller row lengths is suggested if you are unable to create pressure with a pump.

Lay Out the Hose in Your Garden Beds

Start by positioning the soaker hoses close to each plant, about 6 to 12 inches from the base. For areas on slopes, ensure the hose runs across the slope and not up and down. With perennial beds, space the hoses 18 inches apart (for sandy soils) or up to 24 inches apart (for clay soils). For annuals, since their roots are shallower, place the hoses closer at around 12-18 inches apart. Use your stakes to secure the hose in its position. Add manual valves to your rows, this will allow you to control the water flow and pressurize your system. Use high flow emitters to quickly distribute water to your plants.


For trees, circle them using the 1/4" soaker dripline. From there, add a circle of soaker hose every 2 feet inward. Make sure you water the areas directly below the tree's foliage. On mature trees, avoid watering closer than 3 feet to the trunk.

Garden beds, Planters, and Pots

Large pots, barrels, and window boxes benefit from 1/4" soaker driplines. Remember to water them regularly, especially during dry seasons. Use the 6" spaced 1/4" soaker driplines for fast water delivery. For medium to large garden beds use Drip Tape. Lay out the drip tape and use a barb with valve to start each row. Drip Tape can work at pressure as low as 4 psi making it ideal for low pressure gravity systems.

Watering Times

Initiate your watering routine by letting the drip irrigation run for about 40 minutes weekly or 20 minutes twice a week, especially for sandy soils. To check if the plants receive adequate water, dig a hole with a trowel to see if the root zone is moist. Once you've determined the optimal watering duration, you can incorporate a timer for consistency. The zero pressure battery timer is a great option, it requires no pressure to function unlike other with pressure requirements.

Bottom Line

Using Harvested Rain Barrel is a great way to help the environment. It's simple to do and the water you collect can be used to water your garden.

You can explore various design options to further enhance your soaker hose system. Click here to get the perfect Soaker Dripline for your system from DripWorks and ensure quality!