It’s taken a while to find the time to sit down and report on Part B of our earthworks here at Rosella Waters, near Cairns in far North Queensland. Phase I Part A was documented whilst the process was taking place. This latest update however will rely on memory and hurried notes made during the process, together with numerous photos. Large excavations such as the two large dams we constructed in part A are considerably easier to direct and far less time consuming than the finer detail work using smaller machinery as we experienced in putting in Part B.

Once again we had an excellent earthmover that came on the recommendation of the guys who did the two large dams. Sparky, as he is known, is a very knowledgeable and experienced earthmover, having spent a great deal of the last 40 odd years driving a 46 tonne excavator, building large scale dams, roads and “opening up new country”, as the saying round here goes. Now he runs a private earthmoving business and has at his disposal an 85HP bobcat and a 4 tonne mini excavator with numerous attachments. All of the following work was done with these two small machines.

The first part of the process in Part B was to construct a gabion rock wall at the very top of our system, in the gully that feeds our two dams. Previously, we had done a catchment analysis and based on the 1000mm of rain we receive per year, we arrived at a figure of 5,000,000 liters moving through it. We used this figure to calculate levels and engineer our spillways, level sill heights, the freeboard on the dam walls, trickle pipes, lock pipes, etc. The gully in question begins on our neighbour’s property. It is fed from the hill behind it and also from the diversion drains the road department puts in on the dirt road leading to our front gate. The catchment is predominately regrowth after being cleared 30 years ago with two dozers and a ball and chain. The catchment area is not a well functioning bio-diverse eco system and as such there is little water infiltration and a lot of sheet flow that brings top soil/sediment run off into our system. During the wet season of 2008 we did a small trial by hand building a rock wall just inside our fence line to get an idea of how much material would be trapped and how long it would take to fill up. After only 3 rain events, the small rock wall was fully backed up with silt 1.5 feet deep and the moisture remained just under the surface of that material well into our dry season. With that experience and the slight scar constructed at the back of the Lap Pool dam during its construction, we decided on a larger than first thought gabion, to (a) repair the damage caused by the construction of the Lap Pool dam (b) trap silt/top soil and sediment, preventing it washing through our system and ultimately ending up on the Great Barrier Reef, and (c) provide a small scale example of a solution to dry eroded gullies, that run like rivers in the wet, utilizing a “waste” product of local agriculture.

The “waste” product I speak of are the mountains of volcanic rock that many farms in the area have piled up in massive windrows. Farmers spend up to $4000 an acre to pull them out in preparation for planting avocados, potatoes, mangoes, bananas, sugar cane, etc. Rosella Waters sits right on the edge on an ancient lava flow so the farms that surround us are littered with such rocks, some as large as a car down to rocks as small as a grapefruit. We approached our neighbours up the top of the hill, who grow avocados and mangos, and who had recently put in a mass planting of new trees. Prior to that they had a 20 tonne excavator and dump truck working for a week to pull every rock out. They followed this by traversing over the land with a pickup and five workers pulling the grapefruit sized ones out by hand. Anyway, they were more than happy for us to go onto their property and select as many rocks as we liked from the windrows, which they had conveniently separated into different sizes.

Gabion rock wall trapping silt/sediment & top soil

The cost in building the gabion was therefore the time for Sparky to load up the individually selected rocks into his tip truck and then place them one by one with a claw on the end of his excavator arm. The process took two days in total and we estimate that it cost us close to $1800 to build. As we had large rocks to work with we decided against both “keying in” the base of the gabion wall into the side of the gully and constructing a net meshing to encase them in.

The volume and more importantly the velocity of the water coming down the gully in this case didn’t necessitate us doing either. Choosing the largest rocks first, we placed each one exactly where we wanted to create a firm base on which to construct the wall. It was built much in the same way as a dam wall is built, starting out wide at the base, six meters in this case, and tapering up to two meters wide at the top. The height of the gabion is nearly three meters. After placing each rock, Sparky would firm it down, swivel it around until it was firmly wedged. This in itself is more difficult than it might seem and does take time, but it is VERY important to get right. In all, the wall required 7 full dump truck loads of rock to construct. Once the main frame of the wall was complete we got another two loads of grapefruit sized rock which we have since placed by hand to smooth out the top of the gabion, thus providing a great access path across the gully that we can push a wheel barrow across, drive an ATV over or lead a goat and cart. To repair the scars at the side of the back of the Lap Pool Dam, just in front of the gabion wall, we placed some large rocks on the ledge and back filled behind the rocks with some top soil we had had set aside from the construction of the two dams. This was immediately cover cropped with cowpea and a crotalaria variety called gambia pea. All of the seed we used to cover crop was bought from a local seed merchant as seconds, which means there is a low strike rate (around 40%) but at $1 per kilo and having used the correct inoculant, we gained excellent coverage and stabilized the area. It’s important to remember that seed is the cheapest herbicide!

The next element we tackled was the overflow swale and spillway connected to the larger Mushroom Dam at the bottom of the property. We decided that after completing the gabion it would be best to start at the bottom of the system and then work our way back towards the front gate so that by the time it was all done, Sparky could load up and head off without risk of doing any damage with his machinery.

The first swale was only fifteen odd meters in length and had a level sill spillway half way along it that would spread the overflow of the system over a 3 meter wide area right on a broad ridge point, making it very safe to discharge and presenting no danger of causing an erosion gully. The construction of this small element proved to be a major turning point in our working relationship with Sparky. In the end it took the best part of a day to complete, due to a number of factors including our newfound language barrier. There were some important miscommunicated terms that needed clarification as we went: level sill spillway, back cut, swale, swale mound, swale dish, bottom of the swale dish and most importantly LEVEL. The idea that we wanted to construct something that didn’t run and was in fact perfectly level and on contour was quite a paradigm shift for Sparky, as in his words he had “spent his whole life draining landscapes” and what we wanted to do was quite the opposite.

The swale needed to be constructed on a steepish slope and we decided that we wanted it to hold 300mm of water in the base and have the top of the swale mound 800mm high – thus a substantial 500mm freeboard on the swale mound. The freeboard on the dam wall is one meter, so if ever there was a chance of water spilling over it would go over the swale mound first. It is unlikely to occur as we have “over engineered” things, but if it did the swale mound can be repaired with a shovel unlike the dam wall! What we soon discovered in constructing the swale was that due to the slope of the land we just wouldn’t have enough material to make the swale mound as high as we wished. The answer was to dig further up the hill from the back cut, as gently as possible, in a 1:1 cut. We didn’t want to dig too far up the hill so we adjusted the level of the swale mound back to 700mm high and with a three-meter long level sill spillway, the swale mound still wouldn’t be at risk.

First swale constructed leading off the Mushroom Dam

The data records for the region showed that the largest single 24-hour rain event in the last 30 years had been 284mm. We rounded this out to 300mm and built the spillway to be able to deal with ½ cubic meter of water per second. Together with another spillway on the swale connected to the opposite side of the dam wall, we have more than ensured the dam wall’s safety. Another safety margin we designed into the system was a 110mm lock pipe set at the bottom of the Mushroom Dam wall. The lock pipe is 27 meters long and goes right through the bottom of the wall. On the outlet side there is a butterfly valve, which can be opened wide in the event that the spillways aren’t coping. At the bottom of our system, and being our primary aquaculture dam, it also means we can drain this dam if needed. The dam also faces West, which is likely to be the direction of any fire entering our property, so in the event of a fire we have the added security of being able to drain 2.5 mega liters of water in that direction.

For ease of construction we built this first swale with the 85HP bobcat, equipped with a 1.7 meter wide tilt bucket. Time is money with earthworks, so we decided to make the swales a bucket width wide. Sparky started by running across the slope with his bucket following the back cut line we had marked out, corresponding to the high water mark of the dam. The spill was flicked down slope forming the first part of the swale mound. Once we had the basic shape and marked the position of the level sill spillway, Sparky used his tilt bucket to scrape beyond the back cut line up the slope to get the material we needed to gain the swale mound height we were after. We also took quite a bit of material from the area leading onto the dam wall, progressively cutting back to smooth out the sharpness of the cut. Sparky did a great job and we can easily drive through this area and up and onto the dam wall, giving us access to the other side of the property. The swale runs dead level at 300mm deep all the way through, from the exit point at the dam to the end of the swale itself. On the final scraping run we asked Sparky to tilt the blade slightly down slope in the swale dish, meaning that water will be predominated into the swale mound during rain events. With our first swale complete, fully seeded and earthmover trained we we’re ready to attack the rest of the design. Together with a mix of gambia pea, cow pea and pigeon pea we also planted sweet potato cuttings, aibika, cassava, pumpkin seeds, etc… giving us full cover leading into the wet. In the last few days we have started to receive our first rains in 9 months, so now we have a good base in which to begin our major plantings.

The next swale was a short one connected to the opposite side of the dam wall. It was constructed in the same fashion and care was taken again to ensure a smooth driveway leading off the dam wall for ease of access. With not much room to play with within our boundary line, the swale was extended right up to the fence line with our neighbours and the three-meter level sill spillway will serve as discharge of excess water into the creek below, and also as access to behind the dam wall and our Zone IV area of the property.

Moving further up the slope, we then tackled the 25-meter long swale connected to the Lap Pool dam. With this swale we had a few important decisions to make. Firstly it was going to be the Lap Pool’s only swale and only level sill spillway, the overflow from this leading to the Mushroom dam. The placement of this level sill was therefore vitally important as it would be the major source of water that fills the Mushroom dam and we also have future plans for structures connected to the 6m x 3m jetty we placed on the dam. We saw the opportunity for the level sill to be a feature and a potential wet/dry growing area, in close proximity to the jetty and eventual cabin connected to it. We decided to step the overflow down into a further two level sills before it entered the Mushroom dam.

The step down spillways leading overflow from the Lap Pool Dam swale into the Mushroom Dam. Jetty posts in waiting.

In this way, we slow down the volume of water, create further edge and add an aesthetic feature in the process. The level ditches are slightly wider than the level sill on the swale itself and together with generous amounts of cover crop seed, we planted clumps of vetiver grass to further stabilize the area and slow down water flow. We used the same technique on all the level sill spillways. With such an abundance of rock at hand and a couple of quite steep spillways to stabilize, we saw this as our best option. On two steep spillways, we planted out clumps of vetiver grass across the slope, starting at the top and offset all the way down. Then we placed rocks from the bottom up, starting with larger rocks in an arc, wider than the spillway, followed by smaller rocks all the way up the spillway wall face. We left a 200mm space around each of the vetiver clumps and now 3 months later we have a very stable, rock wall face to our spillways, with large clumps of green vetiver grass breaking up the brown.

Back on the Lap Pool swale we asked Sparky to dig ½ meter deep x 1 meter long x ½ meter wide ditches within the swale dish itself. These ditches will hold water for longer than the rest of the 300mm deep swale and as such become growing zones for some wet crops. We now have these ditches planted out with Taro, with water chestnuts on the edges, all of which is shaded by bananas growing at the inside edge of the swale mound.

Lap Pool swale with newly planted Taro and water chestnuts in the pits and banana on the edges.

Again the whole swale was cover cropped with cowpea, Gambia pea, pigeon pea and dotted with cassava, Aibika, sweet potato and pumpkins. The larger long-term support species and variety of fruit and nut trees are now ready to be planted. We had considered putting all of plantings in at the same time but with no rain at all for close to 9 months we decided to get cover crops and shorter term nitrogen fixers going and wait for the beginning of the first rains before putting them in. The earthworks couldn’t be put back to a more appropriate time due to the availability of machinery.

The rice paddy system was by far the biggest challenge. To look at now, it seems all we have done is push a little dirt up to make a wall and dig a couple of holes for the ducks to live near. In a sense that’s true, but the process of constructing the 1:300 diversion drain from the Lap Pool dam to a duck pond connected to a rice paddy (the overflow of which runs along a diversion drain with a 20mm fall over 20 meters, to another duck pond connected to another rice paddy, the discharge of which drops down into a 25 meter long bio-filter which is itself a level sill spillway), dropping water into the Mushroom dam wasn’t that simple! Plus, the overflow of the second duck pond, leads to a short swale with level spillway that drops down to a 20-meter long swale, the spillway of which also drops into the bio-filter before being discharged into the Mushroom dam. Phew.

The rice paddies with bio-filter below. The beach area is on the edge of the Mushroom Dam with the back side of the Lap Pool Dam wall behind it.

A great deal of gravel road base material was taken out of the rice paddy area and we used this to repair/construct a proper ringed access road, our main access road on the property. The road has now been graded correctly so that water will run into drains leading along side it directed to water storages. On the road we have placed 150mm x 50mm x 4 meter long blue gum planks in sets of two, 4 inches apart, at an angle across the road, every 10-12 meters. We first heard of this idea from Rainbow Valley Farm in New Zealand who has the same system on much steeper roads. As water runs over the road it only has a short distance to run before it drops down into these drains that run across the road at a slight angle. By not allowing the water to build up speed over the road surface the material stays on the road rather than down the bottom of the hill, with obvious benefits.

The diversion drain leading to the 1st duck pond needed to fall at 1:300 and be set low enough in the Lap Pool dam so that it was the first water to leave the dam as it filled. We can regulate this fact by capping the end of the 150mm pipe. The level at which we set the150mm diversion pipe was 450mm below the high water mark of the dam which also corresponds to the level of the level sill spillway. That is 150mm lower than the depth of the swale and the level at which water exits the dam into the swale. As I said, setting the pipe at that level ensures we can control when the water heads to the duck ponds. We have a 30,000 L concrete water tank connected to our shed with approximately 100,000 L of potential roof catchment. We needed to decide what to do with the extra 70,000L. In a minor brain wave, we came up with the idea to pipe the overflow through a 90mm pipe down the side of the tank, under the road and into the 150mm diversion pipe with a t-piece. At the entry point into to first duck pond, we have rocked the spill and next to the 150mm diversion drain pipe we have another 150mm pipe under the road that collects all the water in the drain running alongside the road. At the end of the drain along the side of the road we have dug a meter deep silt trap, concreted the base and placed a grill over the top. This will keep silt out of the duck ponds and provide another source of potting mix from the material that does ultimately come from the road.

The main issue we faced with the levels we were dealing with was to get the duck ponds as high up the slope as we could, leaving us room to put in the proposed rice paddies. The duck ponds would end up being quite small as a result and have a 800mm slope at the back of them from the ridge road. We saw this back slope as another opportunity to be creative and decided to step this down in 300mm wide ledges to the high water level of the ponds. The end result is a duck pond amphitheatre on both ponds! This stepped area will be fully planted out with duck habitat and forage, shading the ponds in the process.

Duck ponds at the back of the paddies, connected by a diversion drain. The amphitheatres at the back of the ponds are well cover cropped and stable.

The two ponds are connected by a diversion drain that runs from 1st pond to 2nd pond, with a 20mm fall over its 20-meter length. This isn’t a great deal of fall, but it’s enough. It has meant we have been able to keep the 2nd pond up as high a possible to give us room for the paddy below. The water from the duck ponds are released into the paddies by way of gates we picked up from an old rice farmer up here. They used to grow two crops a season using the channel that leads from Tinaroo Dam as a source of their water. One of the reasons they gave it up was when the cost of water went from $8 p/ML to $18 p/ML. Now they flood irrigate sugar cane instead. We swapped the four gates for a case of beer and made metal plates that slide into the 3mm gap in the concrete gates, to control the flow of water. The same gates are used at the exit end of the paddies, to discharge the nutrient rich water into the bio-filter below before it heads to the Mushroom dam.

The bio-filter that acts a level sill, taking nutrient rich water from the paddies as well as the swale in the background at the base of the chicken tractor system, overflows into the Mushroom Dam.

The two paddies are separated by a meter wide bund and surrounded by a meter wide, meter high bund with a slight grade. All of this will become a growing zone for duck forage, mulch and some soft fruits such as pawpaw and banana. The meter high bunds, once planted out, will become a living fence keeping the ducks in the paddies during the rice-growing season. We plan to grow rice using the integrated rice and duck growing system I had learnt whilst living with Takao Furuno and his family in Japan. Takao is a social entrepreneur with the world economic forum with his rice duck growing system and has an excellent book out through Tagari publications titled “The Power of Duck”.

The short swale connected to the second duck pond drops down into a longer swale, which will form part of our chicken tractor system. This 20 meter long swale lies at the bottom of the contour chicken runs and borders the Mushroom dam. It’ll take excess nutrients from the chicken system and grow some large trees on the north side of the dam, providing shade. Due to this swale being constructed on less of a slope than the first, it was built with the four tonne excavator. Working from the downward side of the swale, the bucket cut on the back cut line and the spill was dropped to create the swale mound. Following Sparky along with the laser we ensured that the swale dish was 200mm level all along. It doesn’t need to be within a mm but it does help to make the dish as level as possible so as to get an even distribution of water along the swale in lesser rain fall events. Obviously the best way to check that level is to fill the completed swale with water and adjust accordingly with a shovel. It is cheaper to do this in your own time than to pay $100 an hour for a 4 tonne excavator to do it.

“Hairy Harry” stands tall on the island at the back of the Keyhole Dam.

The final element to put in was the Keyhole dam at the entrance to our property. We named this pond the Keyhole, as it is the key to the system that connects water on both sides of the property. The Keyhole sits on a central ridge that dissects the property and the idea was to create a small water storage in our Zone 2 area that can move water through either the system described above or to future water storages on the river side of the property, or both. We decided how large a storage of water we wanted and marked out the approximate position of the dam wall for Sparky to follow. We set a target level for our high water and corresponded this to the position of the two swales that were to direct water to the Keyhole via 150mm pipes placed under the access road. The wall was built using the bobcat, layering wetted clay followed by numerous track rolls with the same machine. Using the excavator to dig the hole of the dam, material was mixed using the tilt bucket with me standing close by, hose in hand, making sure there was the right amount of moisture to make the clay bond. Dam and pond walls are all about compaction and with enough of the right clay, a little mixing if the material is good and bad, and the correct amount of moisture, things should seal. We decided to create a small island at the back of the Keyhole as an aesthetic feature, duck habitat and for the fact that the palm we’ve named “Hairy Harry” was too good looking to lose.

Once the Keyhole was built with a 400mm freeboard on it, we set about marking the back cuts of the two swales that were to connect to it. The Mediterranean swale (so named due to quite granite soils in that part of the property) leads out towards the header tank and drops its spill down into the Lap Pool dam. It is connected to the Keyhole via a 150mm pipe, under the road with a slight 20mm drop towards the pond so as to not get stagnant water sitting in the pipe.

The Mediterranean swale connects to the Keyhole Dam via a 150mm pipe under the main access road. The level sill spills water into the Lap Pool Dam below.

The end of the pipe can be capped, if we wish to keep water in the Keyhole dam and direct any overflow via the 150mm pipe under the road on the other side that connects the Council swale to the same dam. We called that one the Council swale because its main catchment comes from a slight improvement to the dirt road the council recently graded. It was graded sloping towards our fence with no drain so in large rain events we would get large sheet flows of water moving through the landscape causing unnecessary erosion. We asked Sparky if he wouldn’t mind creating a little spoon drain 100 meters up to the neighbours gate entrance and directing that water through the culvert under our road entrance. The five meters beyond the culvert to our fence line continued as a drain before entering our property where it then becomes a level swale directing a substantial volume of water through the 150mm pipe, under the road, into the Keyhole dam and ultimately through our entire system.

Considering the volume of material we are likely to receive from the dirt road, we placed a 200mm deep x three-meter wide silt trap just inside the fence line. This can be dug out by hand when necessary. The level sill spillway of this Council swale directs overflow to a gully, which in future may become a dam or a large gabion, subject to future test holes to check for clay content.
Either pipe in either swale can be capped to control the direction of water movement through our system. This small dam feature is something we are really happy with for its aesthetic beauty and complex simplicity in functionality.

This spoon drain runs 100 meters long and will direct a large amount of water through our system via the Council swale that connects the Keyhole Dam.

For our first major earthworks the complexity involved in the design was substantial. It was quite a big undertaking, made even more so by the birth of our second son Dylan smack bang in the middle of it all. At this point I must give special recognition to my darling wife Georgie who at 41 weeks pregnant, kept us fed and watered, took all the photos and spent considerable time standing there with FRED ( Forever Ridiculous Electronic Device) i.e. the lazer level staff and receiver, in 33′C tropical heat. We took close to a year observing the site, designing, listening and talking to others, re-designing and planning the earthworks and the immediate repair work after they’re done. Once the earthworks began, concept became reality and the two can be quite different no matter how good the planning. Each evening after Sparky had left we spent time talking things over and making decisions for the next day’s work. We gave our laser level a really good working over, it has been a great investment; I don’t imagine we could have done all that we did without it.

Now that the mainframe infrastructure is in place, a little water is in the dams and the site is green with cover crops, the system has literally come alive. From seemingly nowhere frogs have descended upon the water storages attracting ever-increasing numbers of birds. The place must look like a red-light sale at a discount store – a hydrated green oasis in an otherwise dry landscape.

Overlooking the system from the header tank. A transformed landscape.

A natural spring we knew existed has started to recharge with the water in the swales from irrigating the cover crops. It moves through the sub-soil leaking out into the side of the dam. Our hope is that this recharged system will help to keep the water level more constant in the Mushroom dam by offsetting any evaporation.

In all, the earthworks took close to two months to complete from start to finish with a total of 16 days of actual earthworks involved. With the start of our seasonal wet season rains upon us, the next three months or more will be spent busily planting, planting and more planting. We know Sparky is coming back when the wet really hits – we made a pact to sit down with a beer together in the pouring rain and watch the system operate in full flight. Through a local NRM group we are also planning an open day, for local farmers to come and see the system. These major earthworks are just the start of a great adventure in the development of our Permaculture demonstration site for the wet/dry tropics of Northern Australia, Rosella Waters.

by Abe Collins & Darren Doherty

Introduction

Keyline Design was first developed by the great Australian, P.A. Yeomans (1904-1984), in the late 1940s & 50s initially as a practical response to the unpredictable rainfall regime he found on his new property, ‘Nevallan’, to the west of Sydney, New South Wales, Australia. Soil Conservation, as developed by the US Army Corp of Engineers was the predominant practice of the time and for a time Yeomans was influenced by this, though soon found some deficiencies with the pattern of water flow its application expressed. Yeomans went on to devote the rest of his life to the promotion, research and development of Keyline Design and in doing so was labelled by Permaculture co-originator Bill Mollison as "…one of Australia’s greatest patriots… ".

Influenced by the likes of prominent organic agriculture figures in Andre Voison, Friend Sykes, Newman Turner & Louis Bromfield (among many others!) Yeomans has been attributed with being the 1st person to accelerate soil formation through the stacking of methods, overturning the myth that it took 1,000 years to create an inch of topsoil. Yeomans proclaimed that "…the landman’s job is not so much to conserve soil as it is to develop soil, to improve his soil and to make it more fertile than it ever was…".

The development of the Permaculture concept owes much to P.A. Yeomans, not only for its enduring and effective landscape patterning, but also for the integrated business framework that he developed over the 40 odd years that he worked in developing a myriad of enterprises around Keyline®. From the 1950 – 1970s there was a nationally (in Australia) published ‘Keyline’ magazine, authorship of articles & books, at least three operational broadacre R&D farms under his control, CSIRO support (up until 1958), a ‘Keyline Foundation’, an established international property design & development consultancy, Chisel Plow, ‘Delver’, ‘Tritter’, ‘Keyline Plow’, Lockpipe, ‘Bunyip Level’, and ‘Ag-Yo’ or ‘Yobanite’ manufacture & sales. How Yeomans managed such a diverse business model over many years is a tribute to the man’s capability and is unparalleled in the Permaculture (or Agriculture!) industry despite the devices of modern communications.

Stunned by the loss of his brother-in-law Jim Barnes, in a grass fire in 1944 on ‘Nevallan’, Yeomans brought to bear his vast experience as a mine overseer and earthmover to capture and store rainwater in large ponds (referred to in Australia as ‘farm dams’) across broadacre landscapes which "so lush and green all year round, they would be virtually fireproof" and droughtproof. Similar climate regions across the world suffer similarly and clearly the adoption of Keyline methods would be a primary form of solid-state risk management for both rural and urban landscapes alike. I commonly get requests from clients and correspondents to design both fireproof & droughtproof landscapes and fortunately Keyline provides the effective template.

According to Yeomans the "inseparable trinity of landscape design" were climate, land shape and water supply – with roads, trees, buildings, fencing & soils being the "more negotiable remainder of the hierarchy". Yeomans labeled this prioritization the ‘Keyline Scale of Permanence’ as a foundation to the process involved planning permanent landscapes. Interestingly, the loss of carbon in agricultural soils is now evident. I commonly say that Permaculture itself ‘lacks a clear decision making process’: the Keyline Scale of Permanence’ and latterly Allan Savory’s landmark ‘Holistic Management® Model’ ably provide the models for the Permaculture ‘toolkit’. These methodologies lack the integrated design principles such as those espoused and continually expanded by Permaculturalists, so combining these approaches makes obvious sense and follows the intellectual pathway led by Yeomans, Savory, David Holmgren, Bill Mollison along with Dr. John Todd , Dr. George Chan & Gunter Pauli among others.

The following article serves to outline many of these processes as part of the ongoing evolution of Keyline or Keyline Design Mark IV as I am calling it, and was developed by Abe Collins & myself for our various seminars.

Click here to download as a PDF (574kb).

We are applying Permaculture techniques to restore the landscape
in the hottest place on the planet

In December 2008 it was our great pleasure and honour to be invited to Iran to work for the Forest Rangeland Watershed Management Organisation, originally formed in 1928 (see Word doc on their work here). We were working with different departments of the organisation, like the Sand Dune Fixation Department that was formed in 1958 for the Bureau of Desert Affairs. All of this falls under the central government’s main organisation of Jihad Agriculture Ministry. We were invited to teach a 10-day Permaculture course focusing mainly on desert rehabilitation.

Permaculture course participants in Birjand in Eastern Iran

The work that has already taken place in Iran is enormous and monumental, and is probably the largest application of good desert repair work in the world. I think it is safe to say it is the largest-scaled effort in the history of the world, with two million hectares of desert project area under rehabilitation. This has been a very, very major effort and still goes on today to repair the long-term effects of desert extension and salinisation in this ancient landscape, a landscape that has enormous diversity and ancient systems with a very, deep-rooted history of human settlement.

Erosion control with gabions and tree planting

Iran has some of the most diverse landscapes anywhere, and is still geologically active from the movement of tectonic plates. Some of the most extreme desert wind erosion sites can be found here, and all credit should be given to the Iranian people and their government, who are making major efforts to rehabilitate landscapes using modern techniques and some rather unusual and innovative cutting-edge techniques for desert rehabilitation. In addition, they are implementing very traditional land use systems using the ancient knowledge of local people.

It was a very unique Permaculture design course and we shared a lot of information through dialogue, as the people that we were working with were all professionals working within the Iranian government from different departments. They took a very serious and professional attitude toward the course information and I believe they learned a lot about integrated design and connected design across landscapes, in particular with swale connections between desert features and the application of size relationship of features and soakage of water through catchment hydrology to stimulate appropriate desert and dry land ecologies to stabilise landscape. The areas that are under rehabilitation are the largest I’ve ever seen and experienced and the seriousness of real work on the ground and the numbers of people involved are the largest I’ve seen or heard of in any country. We should really start to learn from their experience, as they have been able to demonstrate success in some of the most difficult landscapes and situations on Earth.

Sand dune leak point stabilization earth works ready for planting

Wind erosion traps planed to trees

Part of our work with the Forest Rangeland Watershed Management Organisation was also to demonstrate for the Bureau of Carbon Sequestration, which is a project in itself. They are actually demonstrating carbon sequestration because there are ethics involved, and what would surprise most people in the world is that in Iran there are very strong ethical movements to reduce the use of fossil fuels and to make a commitment to carbon sequestration and reduction of global warming. Although their country is rich in fossil fuels, they are committed to demonstrating they have ethics in providing beneficial infrastructure and appropriate alternative technology, particularly in the development of villages for the nomadic people that are still in their landscape and are moving from nomadic lifestyles to settlement. These marginal people are settled in villages built by government organisations and the government is striving to establish biological stability through the design of natural systems around those settlements using appropriate technology like solar powered street lights, solar and wind generation of electricity and large solar hot water bath houses. This is not the type of thing that you’d imagine an oil- and natural gas-rich country to actually focus on. Iran at the time of our work only had 30% of its GDP coming from fossil fuels, the rest being from their own manufacturing and production of industrial products. They are a very, very independent industrial country. In fact, it’s quite surprising to realise how independent they are despite having had two years of official economic sanctions (and actually 30 years of sanctions from western countries, particularly the USA and Europe). This puts them in a similar position to Cuba, except of course Iran is a much larger country with a larger population and a great diversity of natural resources and landscape. They do have a coastline on the Indian Ocean, as well as sharing a border with Iraq, Turkey, Armenia, Afghanistan and Pakistan.

Desert re-forestation work

Wind erosion trap plantings

Despite the cost of fossil fuels within the country being inexpensive, they actually have their larger focus on moving away from fossil fuel dependence toward a more sustainable resource model. Gasoline/petrol when we were there was 10 American cents per litre, super petrol 14 American cents, diesel 1.6 American cents, Kerosene was 1.6 American cents per litre and natural gas was 1.5 American cents per cubic meter. Just about all houses throughout all cities and major towns and villages have a supply of natural gas, so nobody is suffering from cold in the winter. Some areas are mountainous and very snowy and cold, with very extreme variations in the climate, and there is an enormous use of natural gas. I believe it is 600 million cubic metres a day of consumption for natural gas alone, which is a most unusual situation.

The main project site that we worked on was near Birjand and this is out near the Afghan/Pakistan boarder in eastern Iran. Further east of Birjand is the Husein Abad Plain and it was in this district that we focused our groundwork, although the projects of the Forest Rangeland Watershed Management and Sand Dune Fixation Bureau go right through all districts of Iran. At the project site on the Hersinabad Plain we visited during the course we actually went through surveying processes, surveying contours between catchment valleys and looking at combinations of connections between swales of water catchment. These swales would catch to gabions and backflood through silt trap gabion soakage. We found we could actually increase the soakage across broad contours of landscape and generally rehydrate a larger area of soakage, and accumulate that soakage so that we could easily start to re-tree the landscape with appropriate species. This would demonstrate that through the planting of appropriate species, not always native, as there are many non-native trees that are already used to begin repair work before native endemic species can be interplanted to facilitate landscape repair. There are very hardy Chinese species that are already being used by local people in the local organisations.

Overgrazing exacerbates desertification

These swale systems would help rehydrate larger areas and start a faster reforestation, which our students readily understood. There was also an understanding that we need to re-pattern the landscape to harmonise with these particular water soakage contours and therefore readminister the rangeland, because one of the major problems is the use of rangeland by traditional people. There are still a large number of traditional people moving into re-settlement villages and they have a traditional right to grazing land. However, with the increase of population and the increase of grazing stock it makes it very difficult to re-forest areas, so large blocks of areas at the present time are taken out of pasture and other large areas are kept in pasture and are accessible to the traditional people.

Swales planted to trees

We explained how we can rehydrate the landscape on contour with water harvesting swales between landscape catchment features like gabions, very small dams and lemonier rock catchment systems, so we can then actually improve pasture between these contour strips. These contour strips would then actually become viable grazing land for livestock, which would mean a much more intricate management system. That means a redesign of the traditional people’s grazing practices, but then there would be less area needed for the same number of stock. There is a limited number of stock set by the government and each area has set limits to the number of grazing animals allowed. Although the area presently used is large, this could easily be reduced by simply implementing rehydration on contour and re-foresting, reducing the evaporation of the local rain and increasing its soakage, first through reduction of evaporation through soakage as well as through shading of the trees, then the reduction of wind evaporation and also wind erosion by those contours and tree belts. Reduction of evaporation would thus occur in three ways:

1. through infiltration of soakage
2. through shade
3. through reduction of wind

Net and pan water harvesting

This is a standard procedure in desert design systems, using permaculture as an integrated whole landscape design and linking features together. This was a major change to design patterning for the students in their professional positions, and the use of a diversity of pioneer species, and an increasing diversity as landscape recovers, allows the biology and the ecology that we are establishing to actually become more and more diverse over time. There then comes an opportunity to go back into native forests, native endemic productive forests and enhanced native endemic productive forests. Thus, by bringing in productive species that come from climate analogues around the world, we can begin to globally identify similar climate landscapes and pattern systems in like manner.

Gabion silt field

Oil residue and seed sprayed desert sand dunes

We then looked at the traditional systems of landscape features put in over centuries, or even thousands of years, particularly drainpipe overflow. These surplus water drainpipe systems are traditional in Iran for gabions, so gabions can be flushed and overburdens of water can be drained quickly and soakage can be moderated in silt fields behind gabions. This is a unique technique that can increase production in small areas of silt fields behind gabions, thus creating enormous production of wheat and other crops in these soakage systems. This was explained to us and we shared this technology between each other. We also looked at the spraying of oil residues and oil waste products over sand dunes which is a system proposed by Bill Mollison in the first Gulf War in Kuwait, where oil wells that were destroyed and were causing a lot of pollution across the landscape. These oil residues and surplus oil waste products can be used to spray sand dunes after they have been seeded to rehabilitation species and pioneer sand dune stabilisation species.

Bulldozer towing oil/seed spraying equipment into position

This is a system that’s used extensively in the most damaged and most unstable sand dune areas of Iran and has proved to be a great success. Despite being a little more expensive than a lot of the other techniques it has worked extremely well. It was wonderful to see an idea that was proposed by Bill Mollison actually in action and working – an idea that a lot of people were very critical of at the time and said was an extremely radical idea. As the Iranian experts pointed out to us, the oil and oil residues are really only ancient fossilised forest products anyway. They are fundamentally broken-down forests, and to re-apply them back on a surface that is eroding to establish new forest is quite an ethical thing to do.

Geoff instructs course participants in compost-making

We also looked at how we could stimulate and increase soil fertility rapidly through soil biology. There was a lot of discussion about the quality of compost that can be produced, and how that can be measured by looking at the organisms suspended in water so that they can be analysed by their diversity and quantity with a microscope. We then discussed the work of Elaine Ingham and the Soil Food Web and explained how you can stimulate microorganisms with oxygenated compost teas. The stimulation of soil biology could be achieved over a large area with a small amount of compost oxygenated so that the soil microorganisms breed rapidly, and then inoculating the landscape through spraying. This was something that was of great interest, and at the project site of Hersinabad Plain we actually had one practical session where we made a fast aerobic compost and explained the basic principals of compost production. This is something that we would like to help the Iranians extend and promote so that they can speed up the recovery of their degraded landscapes and promote a faster biological recovery. The people became very excited about this potential.

Check dams

After the 10-day course we continued to share many learning experiences with our hosts, and some wonderful Powerpoint presentations were shown to us with visual representations of the valuable and extensive work that’s been done – earthworks, tree plantings and education systems among them. We went on from the Burjand sites and visited many ancient systems, very old earthworks and dams, and traveled through the perimeter of the Loop Desert – a landscape that holds the record for the highest recorded temperature on the planet – 70.4 degrees Celsius. It was winter when we were going through it, and there were small rain events we could witness through the landscape. We went onto other areas and visited sites where there were ancient water catchment systems, very large areas of almonds, walnuts and figs, with small catchments around every single tree. We went onto enormous areas planted in pistachio and many different crop systems.

We were also shown some very ancient cities, ancient markets and many different craft areas specializing in production of fabrics and carpets – of course the famous Persian carpets. Generally we were made to feel extremely welcome and everyone was very, very polite and very, very honourable. There was a great respect for us as foreigners everywhere from the people we were working with and everybody we met wherever we traveled. There was also a great united respect for the Islamic faith and spirituality. Everyone had very strong and very honest ethics. We were continuously shown different products that were processed by local people and traditional crops in the area around Birjand and East Iran. Of particular interest to us was the barberry. Often barberries (berberis vulgaris – a very small red berry that seems to be an endemic and wild species in Iran), were part of meals.

An ancient Almond and Fig system using individual tree water catchment systems

All in all this was a very successful trip. We were taken to some of the most ancient sites where some of the old cultures of Iran, and the world, were centred. The general end result of our work was that we were invited to continue to interact with the Iranian organisations there and the Forest Rangeland Watershed Management Organisation and the Sand Dune Fixation Bureau. We were also invited to become involved in at least two project sites and extend our work through other project sites, and we very much look forward to that as a continuing relationship. We believe the Iranian expertise in desert rehabilitation is something the world needs. Some of the best experts with some of the most extensive long term experience in desert rehabilitation are in Iran, and we would like to be able to share their expertise with many of our projects around the world. We will be engaging in their expertise and calling them in as consultants on many projects. We would like to publish some of their work, so the world can share in the quality of their ability to repair desert landscapes and arid landscapes in general. This we hope to do for them through our website and through interaction with universities with which we cooperate.

Whether it is an issue of conserving water of using suitable plant species, thriving in a desert environment is a masterful act of management. Permaculture co-founder Bill Mollison has spent time in many of the world’s arid regions and here shares his observations on surviving in some of them.

Building Abundance into Sandy Deserts

Why should we garden, when there are so many mongongo trees in the world? – !Kung tribesman

The mongongo tree (Ricinidendrin rautenii) grows in great groves on the crests of sand dunes in Africa’s Kalahari desert. It is a deciduous tree with two sexes. One in every 12 trees in a grove must be male to pollinate the females.

The tree is immune to drought as its roots tap the freshwater table of the sands. It is easily propagated from great truncheons of cuttings set in the sands 50–100cm deep (20-40 ins). These can be selected from female trees of good yield. Nuts buried 50cm (20 ins) in the sand will also germinate and can be used to select new varieties.

The wood, as light as balsa, is easy to work and widely used for small seats, bowls, drums and artwork. The tree has a long life and is hardy. It suffers from no serious pests and withstands frosts.

Thousands of kilograms of nuts can be harvested from a grove. Comparing the nuts with grains, Lee (1976) notes that they contain five times the calories and 10 times the protein equivalent of cooked rice or maize. The !Kung eat a handful (200g or 7oz) of nuts a day, or 1260 calories and 56g (2oz) of protein. This is equivalent to 113g (4oz) of cooked rice and 400g (14oz) of lean beef. The nuts provide about 50% of the food of the !Kung.

Groves of the mongongo trees are ideal for setting out in any dune deserts where severe frosts don’t occur, either for human food or for forage for game and pigs. It is only necessary to select a variety of males and females, take cuttings and grow them on. Extensive plantings from nuts would give future variation for plant selection. We should try to do this if we have sandy deserts or dune areas. Ref: Lee, R.B. and DeVore, I.1976, ‘Kalahari Hunter Gatherers; study of the !Kung San’, Harvard University Press, Cambridge, Mass.

Important Runoff Findings for Rocky Deserts

It may now be possible to reforest the deserts of Israel’s Negev. Recent findings from old lakes and buried soils reveal the Negev area (lat 38 N) was once forested with oak, myrtle and pines. Desertification came more than 2000 years ago with the introduction of herding and agriculture. Today, annual rain in the Negev is usually less than 200mm/yr (8ins) and, at places, more like half that. At Sede Boker in the Negev, pits and trenches dug at the top of the colluvium below the last rocky ledge grow a great variety of trees adapted to arid lands, without additional irrigation – if planted after the first winter rains. For 120mm of rains we get more than a metre of wetted soil, enough to grow figs, mulberry, jujube and citrus as well as pine, Callitris, tamarisk, juniper, oak and myrtle. It seems possible that reforestation could be achieved not only in the Negev, but in all stony deserts where such infiltration occurs.

It is rare to find well researched field data on run-off water, leading to sound strategies for run-off harvest and tree establishment. The record of Sede Boker (Sde Boqer), on heavily desertified hills with extensive cretaceous sediments (typical of many drylands), is well worth noting. The research has taken place for 15 years starting with careful rainfall measurement. It has evolved to concentrate on the fate of water in overland flow and on infiltration – and therefore on where to plant trees on hill slopes in order 1 of streams (headwaters just below the uplands and just below the ‘breakaways’ or where the small streams are well-defined).

Results demonstrated no particular rainfall pattern in the landscape and averaged much the same pattern across hills and valleys. It is a Mediterranean climate with winter rains but more than 80% of rains yield no runoff. Even in areas where stony surfaces predominate, an episode of rain must exceed 5mm (20pts) before runoff occurs. An increase in isopods (pill-bugs), together with more soil salts and a richness of species in the sparse vegetation, indicates that some areas of the slopes infiltrate water. (Neither worms nor termites have significance here as desertification is severe.)

Above the point of infiltration (where the more solid rocky surface of the convex slopes form a ledge or drop-off) and below this point (where colluviums if material wasted from the upper slope gathers and deepens downslope) there is a dramatic difference in both runoff and infiltration.

On the upper rock slopes, an average of 24 episodes of runoff annually provides 3.5 litres of water per sq m per year. On the colluvium, only 2-3 episodes of runoff occur and this yields only 0.5 litres per sq m per yr.
Hence, water yielded by the upper slopes is 12 times more frequent, and seven times heavier (a total of 84 times more plentiful) than runoff on the colluvial boundary. Also because it does not seem to enhance the stream flow (which occurs 2-3 times a year), it is clear this water infiltrates at the base of the rocky slopes and is absorbed by the colluvial mantle. Israeli scientists have found that this runoff pattern holds true for stony deserts in South America and Africa.
Professor Moshe Sharter of the Jacob Blaustein Institute of Desert Research, Ben Gurion University at Sede Boker, explained all of this to me on the site itself.

Liman or Valley Catchment in Israel

Linman is an ancient and, more recently, widely used method of patch reforestation in Israel successful in growing a wide variety of trees. It is essentially a bund of earth about 2m (6ft) high and 4-6m (13-20ft) through at the base which is carefully sculpted across the valley flood-flow.

Rainfall of 70-100mm (3-4ins) and floods two of three times a year, yield enough water in perhaps 10% of the landscape to fill small fields – up to 4 acres (1.6ha) – with floodwater. Any surplus can be split to another liman.

At Wadi Mashash, Professor Area Rogel – who worked with Michael Evenari in the Negev – grows olives, grapes, figs, acacia, eucalyptus, leucaena, carob, oaks, stone fruits and almonds in a succession of liman. Crops or intercrops comprise sorghum, wheat, adapted maize and legumes.

While building the liman, Rogel uncovered buried stone walls, about a metre (3ft) wide and deep across the valleys. It is thought these walls were once a series of “leaky” liman, now silted over, built more than 2000 years ago by Jewish settlers.

To ensure about a metre (3ft) of water a year, liman might not use all of the flood plains. But we must allow about 20 acres (8ha) of runoff to each acre of liman. This proportion can be increased (1 acre of crop to 5 acres of runoff) as rainfall increases toward 500mm (20ins) a year.

The flood levels are clearly marked on the inner walls of the liman by a line of weeds and straw trash carried by floods. Great care must be taken to spill into grassed or stony spreader drains as any concentration of floodwaters causes rapid gullying in valley sediments.

In the last 40 years, hundreds of liman have been have been made and planted to trees, mainly as shelter or forage for herds. Wadi Mashash, however, uses very limited grazing. Even so, many trees are bark damaged by goats. One senses that any reforestation must be accompanied by protection from the numerous herds of goats that traverse the Negev.

Small valleys may be fully bunded across, but liman in the sides of large valleys may have a low diversion bank directing water to the upstream entry of the liman. Spillways are usually close to the entries, often in the opposite side of the liman.