Table of Contents
What You Will Do
- Understand the water cycle and how to apply water conservation measures to your design.
- Learn strategies for water harvesting, cycling, and storage.
- Map and design water flow in the landscape and in your home water cycle.
Big Water: The global cycle
This section by Amy Stross
Water is the single most essential element to all life on earth. There are no organisms that can live without water. It is important to understand how finite this resource is, as well as the factors that are threatening it.The earth’s hydrological cycle describes the continuous movement of water on, above, and below the surface. Understanding how water moves throughout the earth helps us visualize where water is being wasted and find ways to manage this precious resource.
Can you define the water cycle, condensation, evaporation, and groundwater?
Do you know how much water you use in a day? The average American uses 88 gallons of water per day, (if you don’t include indirect, industrial use, which pushes the number way higher.)
Consumer culture also impacts water quality by creating scarcity, pollution, environmental degradation, and corporate control.
Everything from clothes and cars to industry affects the quality and availability of freshwater.
In the U.S. alone, vast underground aquifers that have taken more than 2 million years to develop are depleting faster than the water can be replaced. (source)
There are a lot of politics at play here that have resulted in nearly half the global population lacking access to safe water. The bottom line is that, in the western world especially, we must find ways to respect and conserve this vital and sacred resource as if our lives depended on it, because they do!
Take a moment to read this article before continuing the module.
Watch this 2-minute animated graphic about the hydrological cycle.
Only .5% of all the water on earth is freshwater that is available to us. In other words, our most precious and important resource is also amazingly finite.
What is a watershed?
A watershed is the entire geographic area that drains into the same river or stream. (In the UK they call this a “catchment area,” and watershed is something different.) It is important to understand our place within our local watershed in order to select appropriate water management strategies. Watch this very short video on watersheds.
Knowing where your site is located in the watershed helps you contextualise your design and develop responses specific to that location. If you live higher in the hills or mountains of a watershed your incoming surface water will likely be cleaner than someone downstream, but all water flowing off your property will influence the environment and people downstream. The water will move faster off steeper land. A property lower down in the watershed will have picked up more particles and potential contaminants.
- Can you identify the major and micro-watersheds that you live within?
- Can you find old maps of rivers for your area?
- If you use municipal or city water where in the system are you?
- Which reservoirs supply your drinking water and what watershed are they in?
- Where does the surface rain water and waste, sewer water go after it has left your property?
How does moving water shape land?
As a designer, it’s helpful to understand how water shapes and changes landscapes. This can be learned through observation, and through studying patterns.
Can you identify how streams are different as they flow through mountains vs. how they flow through flat areas?
Deforestation and pavement: their effects on the water cycle and what we can (must) do about it.
All of our daily activities and choices affect the quality of water and subsequently the health of the ecosystem.
The challenge is in identifying how we directly and indirectly affect water quality, and discovering alternative ways to interact with this precious resource.
In this section, we will look at two of the ways through which water purity is threatened, deforestation and pavement, and how we may be able to help.
Forests provide ecosystem services such as storing carbon, cycling water, and providing habitat. But what happens when large swaths of forest are cut down all at once for things like lumber, development, or the creation of products?
The most immediate effect of deforestation is loss of habitat. A forestry expert quoted by the Natural Resources Defense Council describes clear cutting as “an ecological trauma that has no precedent in nature except for a major volcanic eruption.”
Habitat loss is obviously a terrible result, but unfortunately, the consequences only compound from there. As you may recall, trees are essential to the water cycle. Trees absorb rain through their roots and produce water vapor that is released into the atmosphere.
Without trees to encourage an intact water cycle, drought occurs.
Without an intact forest ecosystem to store greenhouse gases, climate becomes less predictable over time. In times of heavy rains, flooding takes valuable topsoil and dangerous pollution and deposits them in groundwater and bodies of freshwater.
With this deposition of sediment, the health of bodies of water declines, and we need more expensive and resource-intensive municipal treatment plants to recirculate sub-par drinking water.
As ecological designers, we must focus on personal practices that can reduce the incidence of deforestation and a disruption of the water cycle:
- Go paperless whenever possible.
- Reduce your overall consumption of consumer goods.
- Buy recycled products and reuse/recycle them.
- Buy FSC certified products.
- Find out about the business practices of the companies you buy from.
- Plant as many trees as you can, as often as you can.
Pavement panacea
The degenerative process is compounded in urban areas, where not only have the trees been long removed, whole cities have been paved over.
Pavement presents a relatively new challenge in human history. Never before have we had so much of the surface area of earth covered with an impermeable substance. During a rain event, we now efficiently whisk away millions of gallons of rainwater that previously infiltrated the soil right where it fell, hydrating forests and recharging groundwater.
In an intact, natural area only 10% of the rain during a rain event results in runoff while 25% deeply infiltrates into the ground. Conversely, in an urban, paved environment, 55% of the rain becomes runoff and only 5% will deeply infiltrate.
Medium water: harvesting and storage for communities and broadscale farms
Water is the most important concern when reading the land and designing solutions for a site. We should always tackle water problems as close to where they originate and as high in the landscape as possible. We look for small scale solutions that are the most practical and energy efficient for a given situation.
Whether it’s water from a municipal source or the rainwater that comes off your own roof, look for ways to reduce water velocity, allow infiltration, and reduce erosion. An easy way to remember our goals for water management in the landscape are the three words slow, spread and sink. In this article, you’ll learn about techniques for managing water within communities, home gardens, and larger landscapes.
Municipal stormwater.
In populated areas, managing stormwater has become a highly regulated, highly engineered, and expensive enterprise. Yet, the level of success (success = clean drinking water and intact watersheds) overall does not match the effort or expense.
In fact, clean water infrastructure in the United States was rated a ‘D’ from the American Society of Civil Engineers in 2013. (source)
Today, paved areas and stormwater conveyance systems move polluted and sediment-filled stormwater faster than ever—unimpeded—into rivers, lakes, and streams. So much for nature’s way of using soil and plants to slow and filter rainwater!
In fact, stormwater runoff is now the number one source of water pollution. Just as alarming is that since rainwater isn’t allowed to sink into the ground, the water table isn’t replenished and thus the water cycle is struggling to remain intact.
At the municipal level, low impact development (LID) strategies are showing promise, even if that progress is painstakingly slow. However, there is hope! Brad Lancaster, author of Rainwater Harvesting for Drylands and Beyond, was able to change the laws that shaped how water could be harvested in his hometown of Tucson, Arizona.
The U.S. Environmental Protection Agency (US EPA) acknowledges the benefit of LID strategies to “…treat stormwater as a resource rather than a waste product…” and “…maintain or restore a watershed’s hydrologic and ecological functions.”
This sounds good in theory, but delivering this goal will take quite an overhaul of existing practices. The success of these strategies will be dependent on the speed with which they can become standard practice.
Here are some of the EPA-approved LID techniques and a short definition of each:
- Rain garden: An infiltration basin. A shallow depression in the ground that catches water from an impermeable surface such as a roof, driveway, parking lot, or even rain barrel overflow. It is planted with deep-rooted perennials that can handle temporary flooding.
- Bio-retention facility: More or less a large-scale rain garden designed by engineers.
- Vegetated rooftops: Green roofs take advantage of an underutilized surface to catch and slow water and sometimes to grow edible crops.
- Rain barrels/Cisterns: Used on a home-scale, rain barrels or cisterns catch and store some of the water coming from a roof. They can be especially useful when connected to the home water cycle. See the Rainwater harvesting section below for more about rain barrels/cisterns.
- Permeable Pavement: Porous pavement allows water to percolate and infiltrate the soil below it.
These types of community based solutions can only have an effect if we couple them with personal and community-scale conservation measures. We must all do our part and encourage conscientious water use at all levels. The result of this paved panacea is often flooding in and around the urban stormwater systems and the waterways that they supply. This rapid shedding of water also carries with it roadway toxins and pollutants that overwhelm riparian ecosystems.
Stormwater runoff is the number one source of water pollution.Problems like this can seem too big to conquer. However, the ability of our ecosystems to self-regulate and maintain freshwater purity is in jeopardy. We must take any action we can, both as individuals and as communities.
We can seek to conserve water in our personal lives and create lasting water management systems within our own landscapes and communities, By designing landscapes that cycle the rainwater back into the system, we can nourish our plants and avoid pollution.
Little water: Closing the loop with your home cycle
The home water cycle begins in the house! Over-engineered, energy intensive, municipal systems pump drinking water into the house, where it is used one time in kitchens, bathrooms, and laundry rooms, then swept away to the sewer.
Graywater and Blackwater
Greywater is the water that comes from bathroom sinks, showers, tubs, and washing machines. Although it would be considered a pollutant if discharged into local waterways, greywater can be a valuable fertilizer for plants. By filtering greywater through plants and soil, it is cleaned before reaching local rivers, lakes, or streams: nature’s water treatment strategy.
Reusing greywater for irrigation gets us one step closer to a closed-loop home water cycle by reconnecting our backyard gardens with the larger water cycle of our bioregion.
One question that often comes up is: “Is it legal to reuse greywater where I live?” This map of the U.S. shows which states have passed greywater regulation. (If you live outside the U.S., I hope you’ll share about your local regulations with us in the Facebook group.)
The gold standard for progessive greywater regulation in the U.S. is the state of Arizona, but this was not always the case. In 1998, Val Little, director of Water Conservation Alliance of Southern Arizona (Water CASA), worked to change the regulations and successfully guided lawmakers to legalize greywater.
Now, residential systems that produce less than 400 gallons a day can be built in Arizona without permits, fees, or inspections. If you’re determined to find a way, laws can be changed and residents can be empowered to actively participate in their own water use and conservation.
There are five common ways to capture and reuse greywater, which will be discussed in more detail in the videos that follow. From the simple to the more complex solutions:
- Dishpan Dump: Place a dishpan in the sink and when it fills up, take it outside to dump. Super easy!
- Bucketing: Remove the trap under the sink and place a bucket underneath the sink drain to capture greywater.
- Laundry to Landscape: This system uses the force of an automatic washing machine’s pump to direct greywater through a pipe into the landscape.
- Shower to Landscape: This system directs shower greywater to the landscape and is ideal for those with a second-story shower.
- Constructed Wetland: This system pipes greywater outside into a series of natural filters such as gravel, sand, and certain plants, culminating in a natural wetland or pond.
Taking advantage of greywater reduces pollution and the strain on sewer systems, adds fertility to the garden, and creates a dynamic, living water cycle within the home that is integrated with the landscape and bioregion.
Don’t flush drinking water!
Did you know that the majority of water use inside the typical home goes to the toilet? The curious practice of flushing clean drinking water down the toilet many times per day has become normal practice in households across the industrialized world.
Here are four ways to reduce the use of drinking water in the toilet, and how to make the toilet a part of your ecological home water cycle:
- “If it’s yellow, let me mellow.” Have you heard this phrase before? It’s an easy practice for cutting down on flushing.
- Bucketing: As mentioned above, bucketing greywater from the sink, or even the shower water as you wait for the water to warm up, is a good use for water that is often wasted.
- Pee-cycling: Simply pee in a bucket and use it in the garden as a fertilizer.
- Composting Toilet: A simple and safe solution using a 5-gallon bucket with a toilet seat place on top, and sawdust for covering waste.
Here are a few examples of home greywater systems in action. Here you’ll meet the homeowner, who shows us where greywater exits the house into the yard, hear about their future plans to integrate it into their forthcoming orchard, and how you don’t have to wait until things are perfect to get started with taking responsibility for your own water footprint.
Rainwater harvesting.
In areas without municipal water supplies, such as rural and off-grid contexts, collecting rainwater is often the only way to supply water suitable for drinking and washing purposes. Drilling a well or bore and pumping water from artesian groundwater is expensive, requires special equipment and technical knowledge and the water recovered may not have the correct mineral balance for human or livestock consumption. For many people, collecting rainwater is a necessity and for everyone else, it is a responsibility.
If you have access to municipal water supplies, capturing rainwater is a very practical way to have multiple components in your system support the single function of water supply. As mentioned earlier, municipal water supplies are very energy and infrastructure dependent and as a result heavily dependent on electricity supply and ongoing maintenance.
Even if your rainwater tank is not plumbed into the house and treated with a filter or ultra-violet light, having rainwater stored in your garden can save you a lot of inconvenience when there are disruptions to the main water supply.
Every time it rains, thousands of gallons of rainwater wash off each roof and into stormwater drains.
This resource should definitely not go to waste! For example, a home with a 1,000 square-foot roof in an area that receives 40 inches of rain per year can collect 25,000 gallons of rainwater.
There are many ways we can keep rainwater from inundating municipal stormwater systems while at the same time take advantage of this wasted resource in our home water cycle.
First, identify whether it would be practical and appropriate to catch rainwater for use inside the home. Rainwater from the roof can be directed into a cistern where it is filtered and pumped into the house for regular household use like drinking and washing.
Then we can use that same water again for things that don’t require potable water, like irrigating the garden.
If routing rainwater inside isn’t practical for a particular home, rainwater can still be collected and used for irrigating the garden or landscape. There are several ways to do this, and some of the most common ways are to use tanks, rain gardens, and/or ponds.
Rain barrels or tanks can be linked together to collect and store rainwater from a roof via downspouts. As the rain barrels overflow, this water can be linked to the rest of the home water cycle.
For example, using gravity and a series of swales, berms, contour gardens, and ponds, we can catch and slow the water, so it infiltrates the soil without causing soil erosion. These solutions add habitat and are cheaper than using a ton of rain barrels by themselves.
In this way, you’ve saved water for irrigation and cycled water throughout the site to catch and hold water in the soil. This helps use water as many times as possible before it leaves the site.
Additionally, rainwater often contains environmental pollutants, but is filtered and processed by decomposers in the soil to a high degree of efficiency. We cycle rainwater throughout a site which filters it, and when it eventually drains away, we send clean water into the local watershed.
Here are Eight Principles for Rainwater Harvesting. Please read them before continuing with the module.
How much water will your roof collect? Try this formula from Toby Hemenway’s Gaia’s Garden:
*Annual rainfall for a given location in the U.S. can be found at https://www.usclimatedata.com/ or at the National Weather Service. Search for similar services if you live in another country.
For more details about this rain barrel and rain garden design, see my article, Connecting Rain Barrels to a Rain Garden.
Rain gardens are another water storage solution in the small landscape. These infiltration basins drain within 48 hours, but temporarily catch the overflow from a downspout or rain barrel.
Place it higher than a garden, and the water will slowly percolate down to garden soils. In their basic use, rain gardens are effective at keeping rainwater from inundating stormwater systems with polluted water.
In fact, rain gardens can filter out 80% of pollution and sediment. Soil is our amazing natural filtration system!
A diversion drain can channel rainwater from a downspout or other source of water to a small pond. Water features like ponds have high ecological value providing habitat and biodiversity, even if they are quite small.
A pond can also be useful for aquaculture (fish farming) or simply enjoyment. High in the landscape, a pond is useful for gravity-fed irrigation to lower level gardens or it can link up with the home water cycle in other ways. We’ll talk more about ponds in the aquaculture class.
Conserving water in the landscape
The water that falls or collects on a site is a precious resource. You can retain water and use it efficiently in your garden or landscape by storing it in the soil and in plants.
Strategies like building soil, mulching, planting appropriately, contouring the land, and thoughtful irrigation will ensure that you have the right amount of moisture for growing food crops that thrive, and for taking responsibility for your place within the local watershed.
The cheapest place to store water is in the soil.Soil that is rich with organic matter will store more water than soil that is degraded or compacted.
For example, the forest floor is rich in organic matter because as trees lose their leaves, sticks and twigs fall, and herbaceous plants die back, these organic materials protect the soil as a mulch and decompose into soil in the place where they fell.
Forest soil is like a sponge. Soft, rich, moist, and aerated, it can absorb an incredible amount of water.
Typically, soil in urban and suburban areas was stripped during development, leaving the land lacking in organic matter and unable to hold water or regulate moisture levels. Water runs off the land as quickly as it came, and dry, inhospitable planting conditions return soon after it rains.
Soil organisms, which help to build soil, leave in search of environs that are more hospitable and nutrient rich.
Building soil is the key to turning this feedback loop around for the better. It’s also an economical way to store water because soil can hold more water than a pond or tank, and will evaporate slower than pond water.
Some strategies for building soil and bringing back the soil organisms are cover cropping, sheet mulching, and worm composting. They add organic matter and nutrients, improve drainage and aeration, and can even act as mulch.
Organic matter builds soil and increases its water holding capacity without a lot of effort on your part.
Mulch with organic matter. Remember the forest floor, where a deep layer of fallen leaves protects the soil? You can mimic this action in your food production systems by mulching with organic materials such as grass clippings, shredded leaves, compost, or using a living mulch like a cover crop. Mulch protects and insulates the soil from extreme conditions of wet, dry, hot, or cold. It regulates temperature, slows evaporation, protects soil organisms, reduces weeds, and prevents soil erosion. Mulching is a simple exercise that has a big impact. It conserves water by increasing the garden’s capacity to regulate water, and through this process, it saves time and effort that another gardener may have to spend irrigating and weeding.
Plant according to water needs.
Proper planting is an easy way to manage and regulate water in the garden. It seems logical, but growing plants in a spot that matches their needs will not only ensure a successful harvest, it will also reduce maintenance. For example, some plants are naturally water plants, and love a moist or soggy spot. On the flip side, of course, are those desert or Mediterranean plants that thrive in dry conditions.
One trick is to observe a site for microclimates, small areas that have special characteristics compared to the overall climate of a site. For example, a shady spot under a tree that stays moist for a longer period of time. Another example would be an edge of a garden bed that dries up faster than the rest of the bed. Planted in a suitable location that matches its needs, a plant will better regulate water and need less attention.
You can also use plants to shade the soil and reduce evaporation. Dense plantings in hot, dry climates or seasons can prevent 60% more moisture loss than regularly spaced plants. Try stacking plants in layers by their corresponding needs for sun exposure.
In the vegetable garden, leafy greens and root vegetables need fewer hours of sunlight and can be stacked with taller plants that need more sunlight and cast shade. Similarly, fruit trees originated on the sunny edges of forest, with tall canopy trees casting shade at their back.
Contouring the land.
Contouring is a cultivation technique that takes advantage of the contour lines on gently sloping land to mitigate erosion and maximize the absorption of rain and nutrients before they rush down a slope.
All points along a contour line are the same height above sea level. You can see examples of these lines on a contour or topographic map. Using a simple, homemade tool like a bunyip water level or an A-frame level, you can find those lines on any landscape.
There are a variety of different techniques that take advantage of contour to catch and slow water. Stayed tuned; I’m on the faculty panel for the next module, on earthworks, where you’ll learn lots more about contouring the land.
Irrigation.
So far you’ve focused on building soil, mulching, planting appropriately, and contouring the land to protect rainwater and use it efficiently. Once you have done all of those things, you still may need to plan for irrigating food-producing crops.
After all, rainfall, even in areas where annual rainfall is adequate, rarely comes in perfectly timed doses. Even wet climates can have stretches of dry periods.
For example, we receive 44 inches of rainfall annually in my region, which is a sufficient amount of rain to sustain food production. We have it pretty good. Still, when temperatures heat up to above 90 degrees Fahrenheit in the summer, with stretches of two to three weeks without rain, parched earth is a common sight.
It’s smart to have one or many irrigation back up plans in place to keep soil moist and keep soil organisms alive. There are many kinds of irrigation systems, and which one(s) you use will depend on your needs and resources available.
Drip irrigation or soaker hoses can be useful. They emit water via a slow drip at the soil level to water the root zone directly. They use less water than overhead sprinklers, and covering them with mulch will reduce evaporation, prevent the materials from degrading in the hot sun, and hide the poor aesthetics.
It’s sometimes difficult to determine whether all areas of a garden are getting the proper moisture, however. Using drip irrigation on a timer at dusk is especially effective at maximizing infiltration and reducing evaporation.
Long waterings every 3-5 days avoids leaching of minerals and a buildup of salt when compared with short, daily waterings.
Overhead sprinklers are not as efficient, but water direction can be controlled more effectively. Sprinklers can be effective with clay soils that prefer deeper, infrequent waterings over frequent, shallow waterings. It’s essential to water at the appropriate time of day to reduce evaporation.
Do not water in the middle of the day in full sun. Using a sprinkler under tree cover is effective for reducing evaporation. Used too often and as a stand-alone solution (without mulch, planting appropriately, contouring, building soil, etc.) it can cause a buildup of salt in the soil.
Using a solar or hand pump, you can irrigate from rain barrels, tanks, ponds, or other water sources. Or use gravity to release water in timed doses from these sources. Use timers to turn off irrigation so water isn’t wasted.Plants and soils are surprisingly resilient when other water-saving techniques in this article are used in conjunction with thoughtful irrigation.
By using techniques like building soil, mulching, planting appropriately, and contouring, you can cycle water through a productive landscape to slow it, conserve it, and use it for your irrigation needs.
Broadscale water management
Managing water on a large scale requires a different set of design eyes. There are two ways to manage water on a broadscale farm: hold the water in the soil, or divert it to tanks, ponds, or dams for later use. Ideally a farm water system would include both.
Keyline design is a concept that can be useful on broadacre farms. A special type of keyline plow oxygenates the subsoil without turning it over like a regular plow does. Used in the right context, it can transform compacted land into rich soil that is friendly to crops and stays moist long after rains have passed.
Keylines and catchments are especially helpful when interconnected with ponds and aquaculture systems. Ponds can be used on larger sites as well as smaller properties to catch and hold surface water. There are many variations of ponds to choose from to meet the specific needs of a site.
Some examples are: excavated pond, embankment pond, keypoint pond, saddle pond, or contour pond, some of which include dams. Useful in a variety of situations, ponds can be an important piece of a site’s water management strategy.
In the class on Aquaculture and Season Extension, you’ll learn more about ponds, and we’ll circle back to Keylines in the next class, on Earthworks. I know we’re bouncing back and forth between a lot of modules here! That’s because water is such an essential part of all layers of your system. Quite literally, the flow of water through your site is what enlivens and connects it, to itself, and to you.
Small check dams made of stone or brush can be placed across a gully, valley, or drainage ditch. The dams catch soil and water to slow and encourage infiltration, and crops can be planted uphill to take advantage of this benefit.
Ponds and dams that are high in the landscape are typically used for erosion control, gravity-fed irrigation (for lower level gardens), and for house and livestock use. Ponds and dams that are placed lower in the landscape are typically used for irrigation, aquaculture, water cleansing, and flood control.
No matter if a site is frequently inundated with water or dry most of the year, there are solutions for appropriately managing water. As designers, it is up to us to identify which solutions (or combination thereof) will be the most appropriate for a site to encourage a well-functioning water cycle.
With water harvesting techniques like rain gardens, rain barrels, ponds, swales, keyline plowing, dams, and more, you can reduce water velocity, manage seasonal flooding, allow infiltration, filter out contaminants, reduce erosion, and hold water for irrigation in systems of any size.
Choosing strategies for climate differences
Global climates can be divided into tropical, arid, and temperate climates, or hot, dry, or cold. Soils and rainfall averages are different around the world, as well. When designing through an ecological lens, it’s important to match appropriate solutions to the conditions at hand.
For example, in high rainfall climates, practices like contour swales and contour gardens can result in destabilization, as water pressure builds up behind the berms that catch and hold water.
Marit Parker, your instructor for Social Justice and Decolonization, writes in her article Why is ‘rootedness’ important, that in her native country of Wales, a traditional method called ffosau dyfru is used, which is an off-contour watering channel.
The off-contour channels slow water, but they direct it to catchment areas, designed to hold larger amounts of water during periods of heavy rain.
Likewise, heavy mulching in high rainfall areas can result in anaerobic conditions, as not enough moisture can evaporate to create homeostasis. This can lead to rotting and plant disease. In desert climates, however, heavy mulches and contour swales planted with deep-rooted perennials lead to improved soils and food-producing conditions.
These are just a few examples. In any case, it’s important to seek out indigenous and historical wisdom for a given location, and to research any techniques for their usefulness in a given situation.
This TED Talk by Chika Ezeanya-Esiobu exemplifies the importance of indigenous knowledge by sharing about Tassa, a traditional water catchment technique in Niger that has worked especially well for food production in the desert compared to Western-imposed solutions, and even better than an expensive, highly complicated World Bank solution.
Likewise, this TED Talk by Indian environmental activist Anupam Mishra exemplifies the traditional water harvesting strategies of rural India that are outperforming expensive, modern solutions.
Indigenous solutions generally respect the sacredness of water. Do you know of any indigenous traditions that can inform us in designing systems that conserve water and rehabilitate degraded or polluted land?
Designing a water system for your site
The aim of the designer.
Keep in mind the aim of a designer in using water when walking through the design process.
Our primary ethic with regard to water is to use it sparingly and maintain water purity.
We can do this by abiding by the following principles in our actions:
- Use water as many times as possible before it passes out of the system.
- Tackle water problems as close as possible to where they originate.
- Slow down water flow.
- Try to hold all water on the land.
- All water leaving your system should be clean.
We can retain water on the land, and keep our rivers flowing by:
- Keeping trees on all hillsides and slopes over 15-18 degrees.
- Keeping all riparian areas such as rivers, creeks, and springs forested.
- Rehabilitating land that is suffering from erosion using systems such as keyline plowing and dams.Keeping bare soil covered with mulch.
Try to keep these ideas in mind as you follow along with the videos.
In this video, I’ll introduce you to my backyard project and two ecological designers in my local area who are going to walk through the design process with me.
Step One: Observation and Assessment
In this video, we will do an assessment of my backyard vegetable garden site to see what unique conditions—such as sun, wind, soil, history of the site, slope, amount of rainfall, and potential for roof water collection—that might affect our decisions with regard to water management. We will ask the question, “What do we have?”
Step two: analysis.
In this video, we dive into the conceptual planning phase, where we take a look at the data we collected in the site assessment and brainstorm various ways to manage the water.
Step three: design.
In this video I show you my master plan for the vegetable garden water project that uses a combination of appropriate solutions from the conceptual design phase.
Summary
This video sums up my design project by offering some words of wisdom about the guiding principles of ecological design.
And here’s my water map for my own home system design!
Homework
As you know, the homework at the end of each class is “optional,” but no matter what type of site you are designing, water will have a part in the system.
Questions for Review
- Where does water come into your site, and where does it leave?
- How many ways can you divert the flow from source to sink?
- It’s important to “plant the water” and then design gardens that makes sense for the water system, rather than putting in a bunch of gardens and scrambling to get them irrigated. How many reasons can you think of that this is true?
- Make a list of potential water-related problems on your site. How will you use design to solve those problems?
- What are three ways your project will help conserve and replenish water in your bioregion?
Hands-On
Use this worksheet to help you read water in the landscape.
Perform a water audit for personal water use in your home.
- How much do you use?
- Map the existing water in the home and landscape. Include plumbing, irrigation, stormwater, graywater, blackwater, and anything else that is already there. Note where each type of water comes from (source), and where it goes (sink). Look for places to divert the flow between source and sink.
- Add a layer to your design to represent how you want to change the way water moves through your site. Consider phase planning for larger or more radical changes, such as moving toward total self-reliance.
- Try for a closed-loop water system in your design that incorporates catchment, diversion, and an obvious flowing connection between elements.
- Carry out an experiment to see water’s effects on soil erosion.
- Set up a greywater constructed mini-wetland.
- Set up a rain barrel, rain garden, or other type of rainwater catchment from a roof.
- Visit a municipal water treatment plant.