Comments on: Keyline Swales – a Geoff Lawton/Darren Doherty Hybrid

By: Nathan

Nathan — Sun, 01 Jan 2012 05:24:00 +0000

Keep it up Cam and for god’s sake put it all in a book so I can buy it. I would also add that the large amounts of soil deposition over millennia in the valleys is part of the higher volume of water storage in these parts of the landscape. Ridges are much more skeletal with in some cases little or no soil to store water in these locations. Having said that I am still going to try out your hybrid idea at my site in Castlemaine – although I am going to be careful of tunnel erosion etc..
With regards to the above comment on the “monoculture aim of equalising water in the landscape” I would argue that the natural variation in this soil depth between ridges and valleys would sort this issue out naturally while at the same time through the implementation of Cam’s ideas increase storage s in these more marginal areas. Species selection to match the goals would of course be another important factor.
Nathan

By: Evan Young

Evan Young — Tue, 09 Feb 2010 02:22:27 +0000

I thought that Darren used kelyine plowing between the tree mounds as well, which creates a lot more water infiltration over the whole landscape. I may be wrong but I was under the impression that keyline plowing increases the recharge ability of the whole area plowed rather than just the point of the swales.

By: Rhamis

Rhamis — Sat, 12 Dec 2009 04:57:01 +0000

Just spotted this…stellar work. This is prime R&D material that needs to be seriously investigated and trialed.

Rhamis

By: Shane

Shane — Thu, 03 Dec 2009 12:26:31 +0000

Hello every one,Before you harvest any water ask what is the desired end result. What is it you wish to grow? Moisture content over a given landscape naturally varies as do the water requirements of various trees. Some dynamic in water distribution will aid you in a diverse sustainable planting design. Supper even water distribution is not a natural pattern I see occurring.The monoculture aim would be to equalize all water over an area. But with no dynamic in water when it is wet every thing is wet and then when it is dry every thing is dry. In harsh environments a good percentage of a property may become unproductive due to too much or not enough water, but with some moderated diversity you can keep enough productive area at any one time to be sustainable. To re hydrate a landscape you start in key points and work out,building resources and adding to each success. Season after season you expand the bio mass and with time even deserts ,via succession can become forests again. The whole notion of having undulations in the floor of a swale is a nuance that has been used by experienced people for many years. This is often done to great effect to create a starting point or to support a specif water loving plant in a broader design. Bill talks of digging soak pits by hand (35 yrs ago) in the floor of swales a meter or more deep and burring straw bales to focus a store of water at a desired point.
Personaly I make lots of alterations to the standard swale to manipulate water to go where and when I want it. I encourage you all to experiment but keep nature as your guide and dynamics and diversity will lead you towards sustainability, and even abundance.

Keep growing, Shane.

By: Ringo

Ringo — Wed, 02 Dec 2009 15:37:15 +0000

Hey Cam,

good to see you still active and doing some writting.Nice theory and great work with the graphics mate.Would be great to see some pics from where you have trialed this and your findings from on the ground situations.
As I am currently in India doing water harvesting jobs I can potentially trial this.As an earthwork guy myself,I would be diligent to make the planting mound uniform.With the changing in depth of the floor level,it could create an uneven fill placement.In areas of shallow cut the mound will/may be low and could be compromized by high water/surge levels in different climates.In areas of deeper cutting the earth removed will take up more space so extra shaping may be required..This is cominfg from a perspective of using an excavator.Using a bulldozer would possibly be a bit trickier as the mound should not be compacted and may be if shaping is required.
Keep up the good work.Email me any further data you have and I will trial some.
Donations are welcomed and appreciated for field research.Ha ha.

Cheers,

Ringo

By: Glen Novello

Glen Novello — Tue, 01 Dec 2009 11:05:39 +0000

Seems that the hybrid approach would require a bull dozer and a keyline plough. I think the beauty of the keyline method is that its much cheaper to get done. I have wondered how much water loss would occur in swales due to evaporation before it gets a chance to penetrate the soil. If the soil has a fair amount of humus and mulch wouldn’t it be able to hold onto water better than in open air trenches?

By: Pedro

Pedro — Tue, 01 Dec 2009 07:20:23 +0000

Hi cam, thanks for the ideas.
I’ve always been of the mind that the way to treat the swales was that the overflow be on the ridge top of the swale. Then it drains into the next one down which overflows to the next & on… but this happens @ the ridge. It’s also captured in a dam @ somewhere between the middle or bottom of the ridge.
Also access tracks are best on the ridgetop too. Aren’t they?? This was the way to combine the need for drainage to the track & in the same drain the overflow for my swales. Also the size of the swale, to me, is dependant on the characteristics of the soil, slope, rain events (well pointed out w/ diags, thanks) & the size of the property. I’ve been involved in putting in a few ‘mini-swales’ & find that they fill up quiet nicely. Perhaps I should’ve put in 1 massive swale @ the top of the property & smaller ones below.
How bout deep ripping a criss-cross pattern in the soil above the swale ( or below, everywhere? only in the valleys? where?)
I haven’t seen Darren’s keyline appropriation but I’ve seen pictures of his ripper, planter, compost tea waterer machine combo. Cool stuff!

By: Ave a go

Ave a go — Tue, 01 Dec 2009 00:16:12 +0000

Hi Hamish -

You should join the PRI Forum if you haven’t already -http://forums.permaculture.org.au/

There are people there that will be able to help.

Cheers,
Matt

By: Evan Young

Evan Young — Mon, 30 Nov 2009 22:36:53 +0000

Swales work on ‘flat’ landscapes. There is no such thing as a truely flat landscape so a swale will catch water. Look at the site of the Greening the Desert video and you’ll see what I mean.

By: jay

jay — Mon, 30 Nov 2009 21:38:36 +0000

heard on the grape vine this was coming, been looking forward to it. very interesting and inspiring. thank you.
J