HOW TO BUILD SWALES - and harvest water

Summary

In this video, the host shares a year's journey in gardening, focusing on soil as the foundation for plant growth. They delve into permaculture studies, showcasing the importance of observing natural patterns and cycles. The series highlights the creation of swales, a key permaculture technique for water harvesting and soil improvement. Expert Jeff Lawton's insights on swale design and function are featured, emphasizing their role in enhancing tree growth, preventing soil erosion, and ultimately transforming landscapes into sustainable food forests.

Takeaways

• 🌱 Gardening is a learning process that involves understanding soil as the foundation for plant growth.
• 🐛 The gardener is experimenting with a worm farm in an old bathtub to enrich soil fertility.
• 🌳 Cultivating fruit tree seedlings is part of creating a food forest, aiming for a self-sustaining ecosystem.
• 📚 Permaculture studies are being pursued to observe patterns and life cycles in nature for better garden management.
• 🌿 The importance of soil conditioners like swales is highlighted for water retention and soil improvement.
• 💧 Swales are described as level excavations that can vary in form and are crucial for water management in gardens.
• 🌳 Trees are essential in swale systems for evapotranspiration, which helps in water absorption and atmospheric moisture.
• 🌞 The potential of swales to increase rainfall through increased condensation, especially in desert environments, is noted.
• 🛤️ Swales can be adapted to various climates and soil types, with different strategies for planting and water management.
• 🌱 The progression of swale development over seven years is detailed, showing how they improve soil hydration and tree growth.
• 🌳 The final transformation of swales into forests over time, with trees taking over the water cycle and soil improvement functions.

Q & A

What is the primary focus of the speaker's garden project?

The speaker's garden project focuses on understanding the soil as the 'stomach' for plants, cultivating seedlings of fruit trees, building a worm farm, and studying permaculture to nurture their garden, which they call paradise.

What is a 'swale' as introduced in the context of permaculture?

A swale is a long, level excavation used in permaculture to intercept and store water, allowing it to infiltrate and recharge the groundwater. It can take various forms and widths and is often used on slopes to increase soil moisture and plant growth.

What is the significance of trees in a swale system?

Trees are essential components of swale systems as they help absorb water, increase infiltration, prevent water logging, and contribute to evapotranspiration, which can potentially increase local rainfall and condensation.

Why is it important to plant trees on the mound of a swale?

Planting trees on the mound of a swale is important because it increases topsoil, provides a place for trees to grow, and helps in the absorption and transpiration of water, contributing to the overall health of the swale system.

How do swales help in desert environments?

In desert environments, swales are crucial for capturing and storing scarce rainfall, promoting tree growth, and increasing local humidity and condensation, which can lead to increased rainfall over time.

What is the role of the back slope in a swale system?

The back slope of a swale is often planted with leguminous trees that fix nitrogen and help with water absorption. The roots of these trees grow quickly, chasing the water as it soaks in, contributing to the overall health of the swale.

How can swales be utilized in urban areas with hard service runoff?

Swales can be used in urban areas to manage stormwater runoff by soaking the water into the ground, promoting tree growth, and reducing the costs and environmental impact of traditional stormwater management systems.

What is the process of rehydrating the soil in a swale system?

The rehydration process in a swale system involves the soil absorbing water over time, with the maximum rehydration occurring around seven years. This process is aided by the roots of trees, which increase infiltration and absorption.

How can the distance between swales be determined?

The distance between swales can be determined by factors such as rainfall amount, soil type, and the mature height of the trees. It can range from three to twenty times the average swale width, depending on these factors.

What are some additional benefits of swales in a permaculture system?

Swales offer multiple benefits, including increasing soil fertility, providing a convenient pathway for transportation, serving as windbreaks in windy areas, and potentially being used for burying organic waste to create rich soil deposits.

How can swales be adapted to different soil types?

Swales can be adapted to different soil types by choosing appropriate pioneer trees that favor the specific soil conditions, such as sandy or clay soils. Over time, as the soil improves, higher quality trees can be planted.

Outlines

00:00

🌱 Gardening and Permaculture Learning Journey

The script introduces the gardener's experience over a year of cultivating a garden on a hill, emphasizing the importance of soil as the 'stomach' for plants. It discusses the gardener's learning process in permaculture, including building a worm farm, cultivating fruit tree seedlings, and observing natural cycles. The script also outlines a three-part video series on swales, starting with an introduction to swales by Jeff Lawton, followed by practical demonstrations, and concluding with the gardener's personal swale construction. Swales are described as level excavations that improve water infiltration and soil health, with trees playing a crucial role in these systems.

05:02

🌳 Understanding Swales for Water Management and Tree Growth

This paragraph delves deeper into the concept and function of swales, explaining their role in water management and tree growth. Swales are described as tree-growing systems that prevent water logging and enhance evapotranspiration. They are crucial in desert environments to capture and store rainwater efficiently. The importance of tree planting alongside swales is highlighted to increase rainfall through transpiration and to prevent soil salinization. The paragraph also discusses the potential of swales to be grazed and how they can be adapted to various climates and soil types, emphasizing their versatility and long-term benefits for landscape hydration.

10:04

🌿 Swale Design and Its Impact on Soil and Tree Health

The script discusses the design aspects of swales, including their widths, depths, and the importance of maintaining a passive water level for absorption. It covers the use of swales in different soil types, such as sands and clays, and the planting strategies for trees on the mounds and back slopes. The paragraph also addresses the benefits of swales in urban areas for stormwater management and the potential to integrate them with various water sources, like roof runoff and greywater. The role of pioneer trees in improving soil conditions and the transition to high-value trees as the swale matures is also highlighted.

15:05

🛤️ Optimal Spacing and Advanced Techniques for Swales

This section provides insights into the optimal spacing of swales based on rainfall and tree height, as well as advanced techniques for enhancing swale function. It describes how swales can collect and accumulate organic matter, contributing to soil fertility and the natural building of soil over time. The paragraph also touches on the use of swales for windbreaks, the creation of soak pans and ponds for water absorption, and the integration of swales with other landscape features for multifunctional use.

20:07

🌬️ Swales as Multifunctional Landscape Elements

The final paragraph emphasizes the multifunctional nature of swales, discussing their use as footpaths, wheelbarrow tracks, and transportation routes in gardens and larger properties. It also highlights the surprising performance of swales in various conditions and their role in the rehabilitation of forests. The script concludes with the gardener's intention to share more about swales and their benefits, inviting the audience to continue learning about this sustainable landscape technique.

Keywords

💡Permaculture

Permaculture is a holistic approach to agriculture and land management that focuses on sustainable and self-sufficient practices. It emphasizes the design of human habitats with the harmony of natural ecosystems. In the video, the narrator is studying permaculture to better understand and nurture their garden, aiming to reverse damage and create a sustainable food forest.

💡Swale

A swale is a long, level excavation used in permaculture to capture and store water, improving soil moisture and promoting plant growth. The video discusses the concept of swales, their importance in water management, and how they can be utilized to enhance the garden's ecosystem, as well as the process of building them for a food forest.

💡Evapotranspiration

Evapotranspiration refers to the process by which water is transferred from the land to the atmosphere through evaporation from the soil and plant transpiration. In the context of the video, it is mentioned as a critical factor in preventing water logging and maintaining a healthy balance of local rainfall, especially in swales without trees.

💡Infiltration

Infiltration is the process by which water on the surface of the ground soaks into the soil. The video explains how swales facilitate infiltration, allowing water to recharge the groundwater and be stored in the soil, which is vital for plant growth and maintaining soil health.

💡Soil Conditioners

Soil conditioners are substances added to soil to improve its physical properties, such as water retention and aeration. In the script, the narrator mentions how swales can act as soil conditioners by loosening the soil and enhancing its water-absorbing capacity.

💡Food Forest

A food forest is a garden or agricultural system that mimics a natural forest ecosystem, with a variety of edible plants and trees. The video's narrator is cultivating seedlings of fruit trees to create a food forest, which is part of their permaculture practice to develop a sustainable and diverse garden.

💡Worm Farm

A worm farm is a system for composting organic waste using worms, which break down the material and create nutrient-rich worm castings. The video script mentions the narrator's experiment with building a worm farm in an old bathtub, showcasing their commitment to sustainable waste management and soil enrichment.

💡Crown Spread

Crown spread refers to the horizontal extent of a tree's canopy. In the video, crown spread is discussed in relation to the width of swales, as it can influence the amount of shade and moisture retention, reducing water loss to evaporation.

💡Pioneer Trees

Pioneer trees are species that are quick to colonize disturbed or barren areas and are often the first to grow in new environments. The video describes how pioneer trees are essential in swales, especially in sandy or clay soils, as they help to stabilize the area and improve soil conditions for other plants.

💡Rehydration

Rehydration in the context of the video refers to the process by which soil regains its moisture content over time, especially in relation to the development of swales. The script explains that the soil's ability to retain water improves as the roots of trees in the swales grow and extend their influence.

💡Groundwater Recharge

Groundwater recharge is the process of replenishing underground water reserves through the infiltration of surface water. The video highlights the role of swales in intercepting runoff and allowing it to infiltrate and recharge the groundwater, which is crucial for maintaining water resources in arid regions.

Highlights

Introduction to the garden's first year and the importance of soil in plant growth.

Continuation of grounding experiments, including building a worm farm and cultivating fruit tree seedlings.

Study of permaculture and its focus on observing patterns and life cycles in nature.

Online learning as a method for acquiring permaculture knowledge through videos.

Introduction to the concept of 'swales' in permaculture design.

Jeff Lawton's influence and contribution to the speaker's understanding of swales.

Explanation of swales as level excavations for water harvesting and soil conditioning.

Role of trees in swale systems for water absorption and evapotranspiration.

Risks of waterlogging and local rainfall deficit without proper tree planting in swales.

Desert swales' importance in capturing and utilizing scarce rainfall for tree growth.

Swale design considerations, including width, tree species, and soil type.

The progression of swale development over seven years and its impact on water absorption.

Use of swales in various climates, from arid to humid, and their adaptability.

Strategies for swale maintenance and enhancement of water infiltration.

Potential of swales in urban settings for stormwater management and tree growth.

Swale's role in soil building and forest rehabilitation over time.

Techniques for increasing swale effectiveness, such as deepening sections and adding wind breaks.

Practical applications of swales in daily garden management and long-term landscape planning.

Reflection on the overall performance and benefits of swales in permaculture practices.

Transcripts

[Music]

g'day

welcome back to the weedy garden a year

has gone by

since i started my garden here on the

hill

far away from any town and even further

from a city

i've learned a lot in 12 months i'm

really beginning to understand how the

soil

is like the stomach for each and every

plant that grows

on this earth i've seen some plants

thrive

i've also seen some die but with each

step

with each wheelbarrow full of soil that

i create here in my garden

i get closer and closer to that somewhat

secret life of plants

i'm continuing the grounding experiments

on building a worm farm in an old

bathtub

and i'm cultivating seedlings of fruit

trees which will

become a food forest

the big news of course is that i'm

studying permaculture

i'm learning how to observe patterns

looking deeper into cycles of life and

nature so i can nurture this little

weedy patch that i call paradise

and share their knowledge with you

it's easy because it's online it's

mostly videos so i can sit back and

watch

listen and learn as long as i have my

computer turned on

and really it's about

reversing the damage

in this next series of three videos i'm

going to share my swale journey

which started with my own words what's a

swale

when i was first introduced to

permaculture back in december last year

when i met

jeff lawton to give you all the info

from the start

jeff has allowed me to share this first

video

it's taken from the online permaculture

design certificate

course which i'm doing at the moment

next week i'll post the second video i

made while jeff was here in the in the

weedy garden

showing me hands on how to dig a swale

for this garden

and do it right on the third and final

video in this whale series i'll

show you how i built a swale

for my food forest weedy garden style

i'm really honored to be able to share

the journey with you

by the end of this little video series

on swales

you you'll be able to harvest and

utilize water wherever

you live in the world

welcome to the swale series and now

i'll hand you over to jeff okay

let's have a look at swales swales

are long level excavations that come in

many

forms and widths they can be just small

ridges in gardens

or rock piles across a slope or

excavated hollows in flat lands and low

slope landscapes they're not elements

that fit into

steep landscape like

soil conditioners swells loosen soils

and absorb water storing it in the soils

and the sediments

they intercept sheep flow

and let it infiltrate recharging

the groundwater overland flow is

interrupted for a few hours or a few

days

and then infiltration becomes

regularly downwards water moving at

right angle the condor down towards the

ground waters as a recharge

into the soils and assisted by the

tree roots trees are essential

as components of swale systems

so most of the time are swales

on slope

they're a mound excavated

out

from the trench to the mound and our

topsoil

is increased at the mount and it's loose

most of the time we're planting trees up

on the mound here

and just below in deserts we

may plant inside because

we've got less rainfall and it's hard to

drown the trees in the desert

so you may move inside but the

infiltration of water is at right angle

of contour and it plumes away

as it sits here and then soaks in

we also plant the back slope often

leguminous trees on the back slope here

fixing nitrogen and the

roots here help the absorption

so the roots grow quickly chasing the

water as it goes down

slowly soaking in

swells without trees risk water logging

and local rainfall deficit because

of the lack of evapotranspiration

and the potential of too much water

storage

because they're on contour interrupts in

the sheep flow

they stop all the water moving past

just temporarily and then just soak it

in

that water disappears into the soil

the trees take some of that back and

transpire it to the atmosphere

tree planting must accompany swells in

all areas so

swales i like to say are tree growing

systems

and it's of most utmost important in

deserts

where there's so much rain that's needed

so there's a chance that as you

interrupt the flows of rain that come so

infrequently and often in large events

you can stop it soak it grow trees that

transpire

more water to the cloud base because the

chances can

increase the rainfall it will definitely

increase the condensation in deserts

the potential crayon spread of the

fringe in trees

so as the trees grow

the crown spread from one side to the

other

shading the swale

this is what we need to understand

the width of the swell can be governed

by

the crown spread that will shade us well

further reducing water loss to

evaporation and dissolve in salt

concentration and water loss

because this water won't evaporate it'll

soak

now the back slopes and the inside

trenches the swells can be grazed

it's possible to run animals in here and

put temporary fences up

and graze animals on the back slope up

to the inside of the mound

eventually it won't make

any difference but grass in this well

won't have the same effect as the trees

grazing between the back slope

and the hangover forage from the swell

trees can be quite beneficial

because the maneuvering here in the

swale

when it rains dilutes right the way

along the swale you get an

even dilution of manure all the way

along

and that's soaking in

but you can't expect grasses and

herbaceous

growth to have anywhere near the same

evapotranspiration

to the cloud base you've got to have the

trees with the deep tap roots

to increase that absorption

swells can be wildly widely used across

the climates

dry land areas they can be very large

because you've got to stop as much rain

as you can when it comes in those large

events and soak it in

and get through most of the year

reassuring your landscape of trees

tree growth giving you shade tree growth

stopping evaporation from wind they also

of course work in humid tropics and

humid cooled or cold climates

and the hydration of the swell builds

over about seven years

each year year one year two year three

year

four it gets up to about year seven and

you've got

the maximum rehydration plume

where each time it rains it comes a bit

more and then you get to a maximum

and it will fully hydrate

to the maximum size and then

quickly drop off the bottom they'll be

recharge the maximum recharge to the

ground water

so you have a dampened hydrology that

wets up as

quickly as possible water available from

wet season to dry season

it's it doesn't matter that it rains in

winter and you'll grow in season is in

summer because it extends

over one season

and the roots reach their maximum

influence

at about seven years so the roots of the

trees

are coming down and they're increasing

the infiltration

effect essentially swales are always

perfectly dead level with no water flow

so water sits passively rises like

a tide and then soaks in

they're not compacted and they're not

sealed they're

made to soak they're uncompacted

swell widths and swell deaths can vary

in relation to the size of a property

small properties small swells of course

large properties can be quite large

slope can make a difference the speed of

infiltration

on local soil types

shallower wider swells in sands

and narrower deeper swales often in clay

fraction

soils and after one or two good soaking

rains

you can seed and plant your swale to

trees

on both banks because you've got a

certain amount of soak on both sides

capillary action will take the water out

to the back slope

and on down and it will take a few years

to

over shade this whale base and

accumulate

humorous relief drop there will be a

certain amount of

leaves coming in an accumulation of

humus but there will be atrophies a lot

of leaf drop from the actual trees

and as efficiency increases extra water

can be led in

so you can lead in diversion drains

from country picking up water from hard

services

over land flow extra water enabling

planting of high value trees so you can

bring in

different trees as the swale starts to

function better and better

you can increase the quality of trees

and and the swell itself can handle more

and more water over time

so that enables you to move the system

up

advance it in quality

that's what they're all about advancing

the quality of the system

swales can be a great benefit with hard

service runoff

in towns particularly sub-humid and arid

towns

could reduce the costs of the efficiency

of stormwater runoff soaking the water

into tree growth tree growth that could

produce fuel

mulch food products even fire proof tans

all roof water and roof water tank

overflows

grey water waste could be led to swells

and it doesn't really matter if swells

are in sand or in clay in sand or even

cinder ash

they grow trees initially pioneer trees

that slow and absorb and hold water

for longer and once established high

value trees

can then be planted and swells the

opposite end of the scale in heavy clays

work well initially growing pioneer

trees with roots that

penetrate the clay breaking it up and

increasing the absorption

so it's not the material that you're

swallowing through

it's the pioneer trees that you might

have to go to

in sand as you're planning initially or

in clay the different types of pioneer

trees that actually

favor the different extremes of material

and then

as the conditions change as you

improve the absorption as you

improve the fertility then you move into

high quality trees we know

that this works the trees grow faster

and are healthier on runoff fed swells

than trees

planted in open country in arid areas

it's most important we plant trees on

swales

or salt concentration may occur

downhill and collapse soils

so we know the trees are pumping the

water cycle

and stopping the concentrations of salts

swells are just temporary events really

over the

long period of time they're replaced by

trees

trees take over the function

they are the precursors to the

rehabilitation of forests

in a region and they give us that

convenient contour lineage to work with

the base of a swale when we look at the

base of a swale

it can be ripped to increase

absorption it could be graveled

so we can gravel the base with swell

or it could be sanded

and on small swells it can even be

mulched

so you can deep mulch as well in a small

swell in a garden you won't have enough

material for a large swell

or you can put down gypsum to loosen

clay if you're in

heavy clay soils to allow more in water

infiltration

the spoil of the swale is normally

mounded downhill so our top source there

the excavation has come over

to our mound but in flat country

there might not be amount because in

flat country

we'll spread the material out on the

lower side usually

but it won't look like there's a mound

at all

so you'll get a flat profile of a swell

and the distance between swells changes

to country

on hill country the potential vertical

height of the trees

at maturity projected horizontally

to the hill as a maximum density

that's an average sort of approach so as

a hill comes down

and it changes in steepness

where we have our swales

the height of the trees projected back

the potential height of the trees comes

back each time

and that's the maximum amount of swells

we need

so as we go on to the steeper country

that projected height

makes the swells closer together

as we get on the steep it's closer as we

go shallow it's further apart

but when we look down from the bottom of

the hill when we look up all we can see

is canopy

it looks like the whole landscape is

forested but there's lots of

interswell there because these are

actual lines of trees

there's a group of trees in that line

but that's just a rough gauge there's no

exact about this

it can change to country another way to

gauge distance is

three to twenty times the average swell

width

depending on rainfall

most useful average size swale bases are

around

one to two meters and the indus whale

space

three to 18 meters but there's no

absolute average

it's more likely that the closer space

in

in rainfall that's quite large

say 120 centimeters 50 inches

and wider spacing in rainfall of

light small ranges of 10 inches 25

centimeters or less

in humid areas the interswell is usually

fully planted

with hardy species and many of them as

mulch producing species in dry areas

maybe it's quite bare and mainly

functioning

as runoff for the swells themselves

but mulch will blow into swells

and wash into swells as as water flows

it'll bring organic matter in organic

matter will arrive in swales

and find dust and silts build up in the

swale bases

they become deposition systems they're

collecting

all kinds of detritus material

that in itself is increasing fertility

they naturally actually build soils

and over a period of time they will

start to

fill up and become level terraces over a

very

long period but by then you've got a

very large forest there

you don't need to swell or you can cast

sidecast the material out

onto the mound and increase the amount

you can

actually keep redressing it doesn't

matter

you can even put domestic waste and

organic matter

into a swell in buried pits you can bury

pits

in a swell

this is like swale furniture swale

attachments

these will fill up with water and they

will become rich soil deposits

inside a swell either in the mound or in

the trench itself

and on windy sites this whale spoil bank

this swale bank

it's actually a very sheltered starting

place

for plants and trees

and every six to ten swell can be

planted to a wind break

where wind is the limiting factor you

can use the swales themselves as

wind breaks wells and the swells in

between is production swells

so they go into another function

and we know ridges should always have

wind breaks

because ridges are out there in the wind

but also there's more condensation

on ridges and that condensation is a

trickle down moisture

with nutrient and if it's swelling

downhill we're picking that up

and spreading it out

swell sections can be over deepened as

well

so there are places where we can put in

deep sections

and this is most effective in clay

fraction source creating kind of

ephemeral ponds

where if we're in sands we can often go

into

widening for more effect and

in volcanic fraction soils which are

like sands as well

very absorbent there we can create

soak pans that readily absorb water

and increase the groundwater recharge

swales can be kept to a convenient witch

so they can be a foot track

or they could be a wheelbarrow track in

a garden or they could be on a small

property

a quad bike track or they could be

a tractor track on a large property they

can be used for transporting supplies in

and produce out and many different

functions

for as well you need to get along as

well to get

material in to mulch to compost to

fertilize to water possibly in really

dry periods

you might want to flood a swell if

you've got dams uphill

and you need to get product out they're

a convenient way

to get across country because they're

perfectly level

we are continuously surprised at the

performance

and function achieved by swales

[Music]

thanks for today and thanks for watching

i'm going to go and have a bath now

you