5 Ways To Harvest Rainwater For Your Permaculture Garden

Water is by far the most valuable resource in a Permaculture Garden. There are no gardens, no grazing, no trees, and hence no sustainability on any farm or homestead if there is no water. Harvesting, diverting, storing, and reusing as much water as possible is usually emphasized in permaculture design, whether above or below ground in some reservoir.

Water Collection Barrels

Each Permaculture garden has its requirements when designing a Rainwater Harvesting system. Watershed collected from roofs, mountains, tarps, or anywhere else must be redirected and stored above or below ground in barrels, swales, keyline design, rock trenches, gabions, and dams.

The five ways of harvesting rainwater we will be looking at can accommodate any size, requirement, or budget when planning your Permaculture Garden. We’ll also look at some rainwater harvesting regulations since some states prohibit rainwater collection.

5 Ways To Harvest Rainwater For Permaculture.

Rainwater is such a valuable resource when you have a Permaculture garden. Every time it rains, you might think, “how can I capture all this water and somehow save it for those dry days.” Check out how you can do it below:

The Rainwater Barrels System

The Barrel System is probably the most common way to collect rainwater. Most people today live in a house with a roof that can be used to harvest rainwater. A carport or shed roof can also be used for this purpose.

This system (of rainwater harvesting) puts a barrel at the bottom of the rooftop and lets the rainwater fall into it. It is more efficient when there is a gutter system attached to the roof with which it can easily direct the water into the barrels.

These barrels can be above ground or below ground, depending on the circumstances and requirements of the owner. Each of these methods has specific pros and cons to consider.

When employing this approach, keep in mind that the initial rainstorm of the season (first flush) will not be pure water since it washes your roof clear of all old dirt and debris. Allow this First Flush water to drain away from your barrel system to avoid contaminating the water supply.

When using water from this system for human consumption, purify the water first using one of these three systems.

  • UV Filtration System: The ultraviolet (UV) light wavelength disrupts the DNA of living creatures and infectious microorganisms to prevent infections and inhibit reproduction.
  • Pulsar Quantum Water Filter: US Water Systems created this filter, which employs a positively charged surface on the filter material to trap electrons in microorganisms. On touch, the activated Silica ceramic surface kills.
  • Filters Utilizing Gravity: This filter does not require any energy and is one of the most cost-effective filters available. To use it, pour water into the container from the top and filter down. The downside of this filter is that you have to add water to the system to be filtered manually.
Rain Water Collection

Harvesting Rainwater With Swales

A Swale is a simple trench widely used to water crops in Permaculture. They are dug perpendicular to contour lines to capture water flowing downhill. Plant trees on either side of the swale to aid water retention, topsoil erosion, and nutrient loss, and over time the water in the swale will seep into the ground, building up soil fertility.

When the season is over and the swales are dry, use the water collected in the barrel system to irrigate your garden. By combining these two systems, you maximize your water collection efforts.

Using Keyline Design To Harvest Rainwater

Keyline design is a more advanced landscaping method used in Permaculture to catch as much rainfall as possible. It employs an in-depth examination of the land’s Keylines to determine the best spots for efficient water gathering.

The placement of roads, homes, fences, sheds, animals, and gardens are all meticulously laid out around water gathering spots. Therefore, only people committed to the Permaculture way will use keyline design for farms or homesteads when designing and creating the layout.

Rock Trenches And Gabions For Harvesting Rainwater

Desert-like places where rainfall is scarce use rock trenches to harvest rainwater. These areas receive most of their rainfall quickly and in a short season, and rock trenches are the most significant way to capture, redirect and dam up this water.

Gabions are wire baskets filled with rocks to build a wall-like structure to restrain the water flow. Smaller, moisture-absorbing stones fill these Gabions, allowing some water to filter through while redirecting the rest. After the rain, these stones release the moisture back into the ground. Gabions aid in preventing topsoil erosion.

Harvesting Rainwater With Dams

Building a dam or many dams on a piece of land is an excellent technique to gather massive amounts of rainwater. This option is not for everyone because this requires a more considerable amount of land, such as a farm. The overflow of one dam might become the inflow of the next, enhancing rainwater collecting during the rainy season.

There are factors to consider while designing and constructing a dam on your property:

  • watershed
  • upstream
  • downstream
  • inflow
  • overflow
  • seepage
  • wall/slope stability
  • silt retention

This list is by no means all you need to consider.

Properly monitor the dam’s health to not pose a hazard to the animals and people in the vicinity.

Small Dam

Planning Your Rainwater Harvesting System.

When you initially begin harvesting rainwater, it is critical to understand where your water is coming from (watershed) and flowing too. Begin at the top of the highest point and work your way down to the bottom. The ultimate goal is to collect the water, slow it down, divert it to where you want it to go, and eventually allow it to permeate back into the ground gently.

It’s worth noting that there will nearly always be overflow. Most of the time, rain comes down quickly and furiously, seeking the quickest path. Planning for drainage or flood is so critical while designing your system. Please don’t allow the overflow to go to waste; devise a method to capture it as well.

To maximize your collected water resource, use an organic ground cover to act as a so-called sponge to soak up or hold the water. Plants, trees, grass, or mulch are good ground covers to capture and retain moisture.

Is Harvesting Rainwater Regulated?

Rainwater is a valuable resource, and once it falls on your land, it is yours to use as you see fit. Colorado and Utah are the two states in the lower 48 that are currently tightly restricted to prevent homeowners from gathering and using rain that falls on their property.

However, in most states, rainwater harvesting is either unregulated or actively encouraged by the state government to measure water conservation, stormwater management, and water availability.

Common-Law Surrounding Dams

The owner bears the obligation to keep the dam safe. A dam failure that results in an uncontrolled reservoir discharge can have disastrous consequences for people and property downstream.

Tens of thousands of dam owners in the United States face responsibility for the water contained behind their dams. Maintenance is critical to preventing collapse and reducing the owner’s liabilities.


Permaculture design emphasizes collecting, holding, redirecting, and reusing rainwater as much as possible. These five ways of harvesting rainwater can accommodate any size, requirement, or budget for capturing and storing the precious rainwater above or below ground in some reservoir for the distribution system.

Plan your Rainwater Harvesting system from the watershed to where the water will eventually end up in your garden; consider rainfall, reservoir, overflow, health risks, upstream, downstream, and complying with local regulations.


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    Author, blogger, podcaster, homesteading and permaculture enthusiast. I have a passion for sharing what I learn and helping others on their journey. If you're looking for me, you'll usually find me in the garden.

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