COVID-19 Community Resilience & Permaculture Course

Session 10:
Water Management

In this session, we will show you what you can do to manage water and keep water on your side. In permaculture, we understand water as an energy flow that we want to keep on land as long as it benefits our system. That’s why Permaculture design tries to harvest, retain, and rescue as much water as possible before it is lost from the system.  After this session, you will 

• understand why is water so important?

• be introduced to the main facts about water

• learned about the 5-S of Water management

• get an idea why soil is the largest storage.

Watch the video, read the text, and finish the learning exercise to complete this session of our Permaculture & Resilience free online course.

Video: Session 10 -Water Management-

Why is water so important?

Access to water and water management is always the number one priority for any permaculture system. Water is essential for everything so it is very important to know where your future water will come from. When looking at what characteristics of your land are hard to change, the number three factors would bee topography,  access, and water. During your design process - especially in the survey and analysis phases it is important to have an extra eye on water. Water comes with a lot of destruction and needs to be managed in times of heavy rains or floods. During other times water is desperately needed for life to develop. This makes it the number one priority for your design! 

Plants can not live without water, this is true. And it illustrates the issue from a more general perspective. In each and every climate and region, you have native plants that are used to coping with the framework conditions surrounding them. You will see a selection process happening during longer periods of droughts, where some species will not be able to adapt and new species will develop and take over. This is kind of normal but also shows how important resilience for an ecosystem is. The status of resilience in each ecosystem will determine how well the entire system will be able to cope with a longer absence of water. 

Water and its impact on your design

Accessibility to water will limit your possibilities as a designer to the native species and make the establishment of new and more diverse systems complicated and slower. You might see it as one of your limiting factors, or you might understand it as your way of restoring the ecosystem and accept the challenge of long periods without rain. As permaculture people, we do not look only for the land that is super easy to work with, we actually look for land that people don’t want to work within a conventional way. These are the areas that need special care and permaculture knowledge to thrive again.

Facts about water

Most of the earth's surface consists of water. This means there is much more surface area covered by water than there is land. How can it be that water is so important for permaculture design if it is available in such quantities? Well,97% is saltwater so the majority of global water is not directly beneficial for most land-based plants, animals, and land-based life in general. The remaining 3% is freshwater and, again, not all of this amount is accessible. Out of the remaining 3%, 68.7% is ice or permanent snow, 31% is groundwater, and 0.3% is lake and river water. Bringing it back to the entire amount of water on earth, we have 97% salt water, 2% frozen, and 1% available freshwater. This is the reason why permaculture design projects result in low impacts on natural resources by trying to mimic more closely the natural water cycle process reusing and cycling water again and again through the ecosystem.  

5-S of Water Management in Permaculture

How can we manage to keep all or at least as much water as possible on our land? Where can we put it? Most important before defining your water management strategy is checking on your climate conditions and your limiting factors when it comes to water. You want to create a system that takes as much water as possible without harming your ecosystem. So if you have heavy rain or even flooding over a long time you also need to have strategies in place to mitigate the uprooting of tree roots or other damaging effects of water. The 5 S of water management helps you to figure out the right water management strategy for your project. So keep in mind: Slow it! Sink it! Spread it! Store it! Share it!

 
Slow it!

Since water comes with a lot of energy, you want to slow it down first. You want to manage the energy to reduce the loss of topsoil and reduce other destruction that water can cause in the first place. Slowing water down also helps your ecosystem to take more of your water into natural storage. The slower the water is passing through your land, the more time and space your ecosystem has to take as much as needed. Swales are permaculture classic to slow down water -P. A. Yeomans' keyline design first used them in Australia in 1940 by. In short, it is a system of amplified contour ripping that controls rainfall-runoff and enables fast flood irrigation of undulating land. 

Swales in Permaculture

Swales capture water in the landscape - slowing runoff and creating passive irrigation.  They are shallow trenches dug along the land’s contour. The downhill side of the trench is supported by a mound reusing the soil from the trench. All points along a contour line are exactly the same height above sea level. Therefore, a trench along the contour captures water in the landscape, slowing (and spreading) it across the contour line. This action reduces erosion and retains water where it is needed.

In contrast to Keyline design and swales where earthworks are needed, you can also work with plants like living mulch, trees, and other ways of slowing down the water more naturally. The use of native plants, in particular, can provide much-needed habitat, slowing the water and acting as biofilters for harmful pollutants all at the same time. Be sure to place plants best suited to wet conditions in the center, moving from seasonally wet preferences into dry conditions towards the edges for best results.

Sink it!

Once you slow down water it is about getting most of it into the ground. Swales work again to increase your land capacity to absorb water and recharge the aquifers. Working with the soil is a pretty appropriate method to increase the absorption capacity of your land. Water can easily sink into healthy soil rich in organic matter. 

Spread it!

Diversion drains are used to channel water from one location to other parts of your land and/or to storage locations. They are gently sloping drains used to lead water away from valleys and streams and into storages and irrigation systems, or into swales for absorption. Storing it first in one place and then using an irrigation system is another method to spread your water not only in terms of space (spreading it over your land) but also in terms of time.

Store it!

You have different ways of storing water. The first one is soil storage by planting trees, mulching, integrating trace elements, and following non-destructive agriculture. Soil can contain many times the water of open storages or streets and is the most natural way of storing water. It is also increasing the resilience of your ecosystem like the natural water available for plants increases. Ponds or dams are an alternative option to store water in large quantities.

A third one would be tank storage, where you harvest rainwater from your roof areas, roads, etc. If done in the right way, you can create your source of drinking water. You can also use it for watering plants. If you are living in a more urban area, rainwater catchment is your number one strategy. As most rain water is going directly into the sewage system, you are saving and reusing it. Rainwater catchment will also reduce your utility bills as you can use it for watering your plants. 

Share it!

Permaculture is following the 3 ethics of earth care, people care, and fair share. By filling the aquifers you are sharing your water with your neighbors and with the ecosystem surrounding you. Therefore it is always essential to store as much water as possible in the soil and the aquifers to recharge groundwater and use water in a sustainable way. As you share it with others by storing it in the soil, it is also important to have additional storage capacities on your land. 

Water management in short

Water access is such an important function. So, of course, you want to have it backed by more than one element. When it comes to water I would go for at least three elements to ensure your access. And always remember the 5 s of water management. Slow it! Sink it! Spread it! Store it! Share it!

Learning exercise

Observe your land and get an idea of how you could ensure that most of the water hitting your land can cycle within your ecosystem following the 5-S of water management.