lease into streams, the water that leaves your property, will be clean water.
Now you may not have the space to do all that, but, believe me, you don't need much space. In a mini-system we can do all that from here to the window. In clump, clump, clump, I can take you through a rice patch or a very high nutrient demand patch, or the taro patch; next, and algae-eating fish; into a rice patch; into a mussel pond with watercress. Now what we have is fairly clean water running out. Then you can let it go off. You can do all that in a space the size of this room.
In many places, of course, the keyline system is not an applicable way to treat your water. These are places in the Ozarks where people are sitting up in little headwater valleys, away above any keyline. They are sitting on tiny plateaus. They call it a cove.
Now you ask me, "What is the least slope you can put this biological net to use on?" There is no such thing as a least slope. We have country at home that has a three inch fall in a quarter of a mile. That is a least slope, and you can still use this system perfectly well on that. At that point you can swale it. You can actually go below the surface, dig out ponds that are below grade, that do not perch on top of the ground at all. The main volume is below the surface.
Just to summarize, I will run through it again. We first gathered clean water at the highest point for domestic uses. We added nutrients to water that we ran through our plant system; then we ran it off into marsh, carrying food from the natural productivity system to the trout; after converting nutrients to biological forms, we release clean water back into the stream. We can accomplish all this within a vertical drop of six feet, going from zone to zone to zone. So we are not talking necessarily about giant systems--we can be talking about real little systems. Once you have worked out a technique for this form of landscape, you will find yourself hitting this situation repeatedly. It is the classical humid landscape.
You will be recognizing it everywhere; you will be spotting saddle dams out of your car windows.
Right around here, and north and south of here, and increasingly as we go north toward Canada, you have very low grade landscapes with ice built bottoms, that have very slow water movement through them. They are basically marsh land. They are very cheap water storage systems, very cheap marsh systems. Very low walls give you very extensive ponds. Keep your eye out for that kind of landscape. It is often very cheap land because cattle can't move around in the marshes, and the hills may be quite dry. Where people can't run cattle, land is sometimes cheap. If you can buy that land, you can get miles of water for very little Earth moved. The best design decision, then, is to go into aquatic production, because the site suits to that, not to dry land production of cattle or corn. We spot those sites for clients who want to rear fish or trout or wild rice, or something else. There are also occasional sites where you have a basalt dike across the landscape, which in geological times formed an ancient lake. Then the waters broke through the dike at one point and the river went on out, and what you have left is an extensive marsh with a very narrow exit and very steep shallows to the exit.
The value of these high lake systems, saddle dams, and high meadows is well known. They afforded the traditional rich summer pastures used extensively in Switzerland and all cold climates as summer grazing meadows. Here is an excellent reason for opening up the flat ridges there. As you get closer to the coast, increasingly alkaline conditions commonly occur. Then you get a copper deficiency in animals. Their hoofs fall off; they aren't thrifty; they get lame quickly. Just shifting them temporarily up to those mountain pastures is good husbandry. All the young people go up with the herds to little huts. Everybody loves that move. These are really delightful times. If properly surrounded and broken up by trees, these are relatively warm. These are very valuable high meadows, and they are valuable for wild life. They break up the canopy of the forest and give essential edge conditions for high productivity.
So the landscape, I believe, dictates in a very logical fashion how you treat it. If you just ruminate on this profile and its thermal advantages, its water advantages, its seasonal advantages, then I don't see any difficulty at all in coming to a set of totally logical decisions about how you begin to treat it, or where you had best place your client within it, or where you would advise him to undertake various sorts of endeavors. As a designer, you will have one last set of resolutions to make, and that will be to increase or decrease the various elements of this landscape according to your client's wishes. If, as typically happens, he hasn't a clue, you dictate the proportional break-up, always maximizing water and forest, because that still leaves the opportunity open for him to decrease them at any later date.
I will now deal briefly with minor form of water storage at great heights that can be hand constructed, called dieu-pond. These are very interesting and semi-mystical small catchments, dotting the British landscape. Mainly monasteries constructed these little catchments. They are said to be fed by 'dieu." It is the god Himself that sends down the rain.
Now they are normally sited where there is a mini-catchment, maybe a little cup-shaped area in the hill. They are hand dug, and therefore not machine compacted. They are often clay tamped. But they need not be. They can be dug in perfectly good holding conditions. Moreover, the material removed from them is laid out on the catchment so that we have the least vegetation there, and consequently a greater run-off into the dieu-pond. Dieu-ponds never dry up. They can range from about three feet to a maximum of about 20 feet in diameter. Two or three people can dig a dieu-pond in a day. Nothing to digging holes. You are laughing? Well, any
3:1 Dieu-Pond Slope way, they dig this little hole so that its walls are three to one, which is about the resting angle of normally strong soil. Now the reason they don't dry up is that as they evaporate, the surface area decreases. They will always have some water. These ponds are the traditional high country watering points for stock. They do need cleaning out occasionally, because that little point at the bottom does fill with silt and leaves. It is an infrequent renewal. In very low summer periods, it pays to hop in there and drag the leaves out.
It is necessary to give the animals a stone access, or walk them into it on the low side. They will of themselves cause some collapse of the edges of it. For normally humid uplands, this is an eternal water supply, depending only on the number of stock watering it.
The builders of these dieu-ponds would never tell anybody how to build them. Old dieu-pond builders used to pass their secret one to the other.
The secret is, you taper it. I never knew how they worked until I took physics. I just knew they worked. I have seen them all around the world-little sloppy catchments. They work because they don't evaporate easily, and they fill from rainfall.
To the ordinary person, they look rather marvelous because there is no run-in, no streams, no springs, and here is a little pond of water. Today, we would hack one out with a backhoe, if not up to using a pick and shovel.
It is very likely that in future times low humid bottom lands, which have the lowest potential for soil loss, particularly if treated in some of the ways we will be discussing, will be the most valuable agricultural land. These areas may be in production long after we have lost all sorts of other soils. This is also where eroded soil accumulates. So those low-lying lands have a large amount of resilience. The only reason why we will be continuing to farm the lowlands is that we will probably be continuing to erode the uplands. Therefore, these are important areas. Very often, our design may keep them out of permanent uses into croplands. You may not see a tree crop that is appropriate to them; and you can often reserve them for main crop purposes. They are important areas, and becoming increasingly important.
We need to deal briefly now with mini-terraces. We may, at times have to site the client ^
where we don't want i.
to. You have clients, quite affluent people, who buy site unseen, subdivisional areas. It often becomes necessary to establish a terraced system for the garden. Design this in a series of planting areas of about waist height, two feet wide at the top, and maybe three or four feet at the base. The base of each tier is a walkway about 12 inches wide. Mulch the walkway and put mulch on the terraces as needed. We don't recommend more than three or four growing tiers in a series, and we don't recommend that they be any more than about forty feet long.
Your client is on this slope, digging in, living up there. He has his chickens above his garden, and the chickens are kicking the mulch downhill, giving him good mulch for his little terraces.
The terraces are along the hill. We let moisture flow down in very fine discharges on these paths. We only permit him three or four terraces, and we don't let them come in a line, we stagger them so that we get a staggering of runoff of excess water. It comes off at separate points, so we get several little runoffs spreading over quite an area of hillside. We will keep the area just below our three or four terraces vegetated with permanent shrubberies, small fruits, brambles, and pumpkins, and things like that. The little terraced ridges are hand-patted and shaped so that the water does not run out of this area very easily. Rain falls, and there is no runoff over these 40-foot ledges.
Now the client can still be in trouble, especially the lady client. The ladies carry all the water. They have to get water on to these high sites with no chance of a catchment up hill, unless they have a friend and neighbor. You, as a designer, can give them two water sources. You can provide for a
catchment tank for water collected from the roof of his house.
Now from our water holding system we dig a little diversion drain and run it very gently across the hill, and maybe even drop a little bit of down pipe in it, directing the water on the trenches. We are not going to get a silt flow, because we have this area mulched, and when the water leaves, we make it run off on an uncultivated site. All the principles are exactly the same as in our keyline structure. We are still running little high keyline dams for him, but everything is small, and his garden is small, but it is productive, very productive!
There are two ways of managing chickens in this situation. You can put the chicken house down at the bottom near the terraces, or you can put it up at the top and the chickens will kick this mulch down to where it stops against this bottom fence. That will be the place from which we collect the mulch for the garden. This is what I
call the kickdown system. We plant this area with chicken forage trees to hold the slope.
Now we will go to a relatively brief discussion of terraces and paddy field.
You can make those on slopes as steep as you like. You can do a Nepalese terrace, you know, in which you get a square foot for every 10 feet you terrace; but normally you make them on easy slopes. I looked out of our bus once in Nepal. We were turning a corner and the back wheels were hanging over here, and there was about a 3,000 foot drop. Out there were two little terraces. There was a gentleman standing on one foot, a hoe on his shoulder, looking up at me. Oh, God, I thought. All he has to do is to lean back! Also, not far away there was a tree growing up like that, and a big branch hanging out over empty space--no terrace below. There was a little girl on the road, and she ran up the trunk of the tree and sat on the branch without hanging on. My God! I can't stand to look at that! Forget those.
What we will discuss now are broad diversion and irrigation drains. You work right in them to see-saw your water across landscape. You usually have a little lip on the outer slope.
The drains fall across slope, and they may be very irregular in their width. There is no need to make them regular. We may be leading these diversion drains from a nearby creek, letting this trickle of water into them. We take this trickle of water and lead it into an agricultural situation.
This is not European gardening. You won't find anything about this in the British gardening book, because it is not straight, but has wavy edges on it; and it just isn't traditional.
Take a brisk look through world literature on the subject, and you will find 60 to 80 common, very high yielding plants that grow in marsh or water. One whole group that may be of interest is the bee forages that grow in or near water. We will deal with them later, when we go into aquaculture.
On more gentle slopes than those upon which we constructed our mini-
terraces, we can indulge ourselves in water terraces, much more simply constructed. We can set up nutrient flow systems that are catching, introducing, and removing nutrients at different points in the cycle, using land animals for nutrient input, and the land plants to mop up the last of the nutrients in the water, while water plants and water animals do their parts in the cycle. We are into slightly different games here than those which we will talk about in aquaculture.
Another thing that you can recommend to clients as very pleasant work is water gardening. You can go into this form of terracing, or into dry terraces fairly fast. They are relatively easy to make and are very stable situations as far as soil loss goes.
Now we will consider the mechanics involved. On very low slopes, where we want to make diversion drains and channels, and in deserts, we make use of a thing called a spinner, which is simply a very large wheel ripping around behind a tractor. This wheel has little cups on it, and you just drive across the landscape and this wheel revolves and chews out a gentle channel and throws the dirt way up here, so there are no banks. The ultimate result is a sort of drain through which the water runs along, not really visible on the landscape except in low-lying conditions. You can drive vehicles and tractors across the landscape and they just enter and leave it without a great deal of fuss.
The width of the drain depends on how big your spinner wheel is, normally maybe four feet wide, and a foot deep. These are very gentle drains for low slope systems. On steeper slopes, the most common form of drain is made by using a tilted blade. The tractor goes on slope here, and blade is on tilt so that it will scrape with a very gentle back slope, and that gives a little wall of Earth on the outside. If it is wide enough, it is also your road, contour road, and it can be grassed. If you have much land and a great big project, and you are meeting all sorts of slopes, including steep slopes, you might even backhoe, or drag line one of these out.
It is handy to put a fence on the upper side, if you are going to fence, so that you can use relatively low fencing.
These are things called delvers, which resemble joined double plows, which can be towed behind bulldozers. They have two wings behind them, and they throw out a V-shaped drain, while the soil is spread out to the sides by the wings. They are low-slope systems. These delvers are sometimes mounted on graders, and you grade across the landscape, delving away at the same time. Graders can be used to grade out low profile drains. So, well, you use whatever machinery you have. For very small systems, you can use just a single furrow plow, turning out a turf; and you can double plow. The farmer can travel along the hillside with his chisel plow or his soil conditioner. Then, fixing a light blade on the tractor, follow along removing the loosened soil. This is a system that is useful when we are dealing with horticulture.
It is normal to grass the spinner drains, just as part of the field.
We will go to dam wall construction.
This is something you need to know, without ever having to do it.
For dams up to six or eight feet high--these are small walls--you don't fuss too much. You give it about two and one-half to one slope; on the rear side, three to one. You make a very broad crown. That's your dam. The broad top should enable whatever construction machinery you need to roll along it. It should be over a car-width wide. You can have a little bulldozer running back and forth while the big one scrapes it up. Avoid including rocks in the soil you use to build your dam. Rocks don't shrink and expand like other materials, and they make for many leaks. So when you strike rocks, bump those to one side. Tamp every foot of your wall as you build it up, using your machines to roll backwards and forwards, so that you have a rammed Earth wall. Up to eight feet, nothing much is going to happen to that. So it is fairly non-fussy.
What we have done is to remove the top soil, get rid of all the sticks and duff. If there is good clay soil underneath, we push this up, roll it down, push Batter slope cross section it up, roll it down, roll it back- for dams oyer eight feet
"You pack the whole core of the dam with selected wards and forwards as we That's it! You can drive across these dams. You will normally use them as low valley crossings, or to drive across gullies.
Your spillways need to be broad. You have your dam across the valley. You cut a spillway into the solid part of the hill, wind it out along contour, letting it shallow out and fail. You don't bring it around down below. If you are going in towards a continuous stream flow, you might very well do one of two things. You can either bring it out and pipe it down here and give that a splash area, or you can put a pipe in the system, an overflow pipe, which you lead out. These are small systems that we can handle in several ways. That is your typical dam.
When you come to building a dam 200 feet long and 20 feet wide, you have to do all this very cautiously. You make a trench here at the base of your dam site. You go down four or five feet until you strike very good clay at the bottom, then you start rolling. You pack that and the whole core of the dam with selected clay.
Otherwise, the procedure is the same as for smaller dams. You do this, and hope for the best! The larger dam is a more serious job. The height of the back of the slope may be about eight feet, with an eight foot down wall. If you run into dry rock, you can lay it on the wall where you would expect some wave splash, if it is a shallow containment. Keep rocks out of your dam structure. On larger dams, you don't want any leaks. Line the whole vertical center right to the top with good clay. That will be a totally impermeable dam. Most soils, however, will roll down to an impermeable soil. If we are working in a granitic country, with course sand, we are not going to get a dam unless we do this core. The core stops the water, and this is what gives the dam stability.
That is how you make dams that stand above the surface. Many dams don't. There are many different sorts of dams. This is a barrier dam that goes across the valley. These are dams that run along contours. They are usually rolled Earth dams, and they are called contour dams. These are the ones you build up on knolls and slopes. Then there are dams below grade. On very flat lands, the way to hold water that runs in is to excavate the dam out, and throw the soil up. They are more properly called tanks-Earth tanks. A spinner drain might lead into one of these Earth tanks, so that a very gentle flow is coming in below ground level. There is no way that these things will ever bust out.
likely to get much vegetation except right at the edge. The steep bank of Earth at the rear, which can be eight or nine feet high, can have trees in front of it. You are in a tropical climate there. If you want to be fancy, you can glass that off and you will have a fantastic situation, with winter reflection of sun giving maybe as much as 60% additional heat. You will have absorption of direct sunlight-- a good heat-up situation. If you want to put bamboo up on top of your Earth bank, you have maybe as much as 60% to 63% additional heat. The Earth bank itself stores heat.
There are two basic forms of bamboo. One is called monopodial, and one is called sympodial. Most of the bamboos are monopodial and form clumps. Sympodial bamboos are more or less runner bamboos. You can put them in here and they go out under the road and come out on the other side. Nobody uses sympodial bamboos because they are all small bamboos, seldom
Now when you are building Earth tanks, you can do all sorts of interesting things. You can sharply pile-up the removed soil to create a sun trap. When your pond fills, you have a good growing situation. Animals can come into this. You can pave that section with stone, if you want to. The deep edge is very abrupt, and you are un exceeding five feet in height. They are good for making arrows. So if you don't need arrows, forget them.
Now the monopodial bamboos are gigantic bamboos, sixty to eighty feet high. Some have big trunks on them. They are slow growing, with nice tender edible shoots. They never become rampant. A monopodial bamboo will form a clump as large as this room if no one is eating off it. If you are eating it, it won't be very big at all, because you eat the shoots.
If we are only going to grow plants in it, we can make our Earth tank about three to six feet deep. If we are going to hold fish in it, we need to kettle them out a little area, a fifteen foot hole somewhere, which you can backhoe in. It only needs to be a couple of feet wide and maybe six feet long for about fifty fish. Your pond does need that additional depth unless you are going to stock it with fish.
These Earth tanks fill from diversion drains. There's no need to find a spring for your water source. We just take a whole big runoff section. You can normally ignore springs in favor of an excellent, cheap site. Of course if a spring comes sited well, that is, if it is at the back of a plateau, we could run a very cheap contour dam and tie in the spring, and we would have a double hit. If the spring is on a steep slope, then you would need a contour plow. In that case, I would simply ignore the spring and bring the water round in contour to the dam. At the spring, you could do something quite different, which is the small, usual spring house with a small tank in it, something totally different from the large storage. If you are lucky, and your spring is above your diversion drain, you can bring it in to the dam. If you have a stream running through your Earth tank, it will just give a slow circulation to it.
Sometimes you will need to use pumps while the bulldozer is going, if you are down below the water surface. We have to use them intertidal-ly, too, when you have to put in 12 hours of fast work--otherwise, glub. When you are digging these, you move your days around to night, if you are digging a big one. And sometimes it rains.
Lock pipes, you can purchase. Those flags you fit in the ditches, you can make them out of a bit of pipe and canvas, and a piece of dog chain. Sprinklers you can buy commercially.
On a flat site you can grade up a wall and get maybe 20 acres of water when it rains, which rapidly dries off.
You can put a little concrete sill in your wall and have a sliding door, called a floodgate, which you can pull up and let all those twenty acres of water out into a chiseled two or three acre area. The floodgate is just like a board in a groove, a simple little thing. You can make those by hand. They all leak a little bit. Expect everything to leak a little bit. Even those lock pipes leak a little. That is normal. Dams leak a little.
We may run this water through our irrigation channel only twice a year, or something like that. Most of the time we let the water go, and therefore we have a normal spillway over the dam.
A dam may have these four things: a diversion channel leading in, an irrigation channel leading away, some device for releasing the water--either a lock pipe or a siphon over the top--and a spillway.
Now when you come to look at the dams--and we will look at a few on this site--the spillway may not go past the dam at all. We might be working on a site in which we have undulating country. We might take a spillway from the back of the dam and lead it into the next valley. There are all sorts of games we can play.
Contour dams are very cheap, no-fuss dams. They are dams in which the actual dam follows the contour and then swings back to ground level.
Basically, the construction is the same as for other dams, but usually you put contour dams on pretty flat land, and you grade them up pretty quickly. They may be six feet high. It doesn't matter if you get a bit of grass or rock in them sometimes. They can be a little rougher. Just roll them down tightly and they will hold.
There are all sorts of reasons for little mini-ponds. Never neglect the little pond. When you are planting steep slopes with trees, you might put a little well at the end of your paths. On a steep slope, it pays to dig these little wells, and line them with plastic, or drop a tire in, which is the quickest. Then when you have to water the slope, you are always carry ing a small amount of water down hill instead of a lot of water uphill.
Another use for mini-systems is when you go to broadscale quail or pheasants. You drop these little ponds through the landscape every 150 feet or so. Just make little holes.
If you have a lot of pear trees, you may want to rear frogs to get rid of pear slugs. You then place these little ponds all over the system.
Well, we have covered the keyline concept, and in with that falls all your lower slope control. And you have this bold idea of storing water right up on the top of the hills.
Only as a last resort do you dam the valleys. You only do that in emergencies, or for the creation of productive systems. Large-surface, relatively shallow, easily constructed, cheap lower productive dams are very good!
In dry areas, and in areas where you are growing very intensively, you might design some form of drip irrigation. Drip irrigation systems are very modest with water. For high value tree crops, they are critically important for establishment, but probably not thereafter.
There is another form of water control that is very interesting, given that we have some water uphill, and given that we have established an orchard on the hillside down below our glasshouse, which is bermed into the hillside directly above the orchard. We will grade little shelves almost on true contour all the way down, at about 40-foot spacing, which is about correct for orchard trees. Down the hill we go, grading these little platforms out and leaving the area in between them in grass. We will then plant our little trees in the outer edge of our swale. We have a pipe from our water source, which is uphill, and we bring it down and stop it.
We can lay a hose in these systems, or we can do another thing that is interesting. We can bury a pipe that comes up in the next system below for reverse siphoning. We can have these little reverse siphons going all the way down the slope. In that way we only need to run the hose in up here. The water enters the highest
swale; it runs along and soaks up all the Earth, then enters the reverse siphon and runs down to the next level, and so on. One person can water hundreds of trees in about an hour.
Then you can do something very interesting. You can plant this swale to a highly nutritious crop, such as white clover. Then you mow the grass strip and throw all the grass on the swale. When it is looking all rich and good, you run along and regrade it, bringing that rich top soil up to your trees. Your trees will get bigger. You grade again, cutting it back a little bit. You do it two or three times. By that time, you have a great mound of black Earth, tree roots growing in it, and a well-defined walking platform that you can walk along, and an easy watering system. No problem with that one.
You stagger your trees down slope. You should also alternate species, putting your narrow leafed species up at the top--peaches and apricots--and your broad leafed species down below, because it is getting wetter all the way down.
That is a very easy way to run an orchard, and a very easy way to set it up. That is real Chinese style, building up the richness in your paths, and then scrape your paths off and put that around your plants. But always keep your stems free. You also have a nice little garden path in which to set your ladders for picking. It's a generally sensible little set-up.
When you get to very flat land with hardly any fall, you can make a trench, a side channel down the side of the field. The side channel has a little fall to it. We block off the side channel at intervals, and through these blocks we put short pieces of four to six inch pipes. We have a plug with a handle on it that fits into those pipes. When we let the water go into this side channel, it fills up to the first block, which we have plugged so that the water cannot go beyond this barrier. We have also done something else. Leading out through the side wall of this main drain, we have many little two inch pipes directing water out into our field. Our side drain conducts water through these little pipes out into graded channels running down the lengths of that field. There are trees on little banks between the channels. Again, this area has been planted with grains, and can be graded up to either bank. So we have banks made up of loads of clover and topsoil, with trees on them.
When all those little pipes are conducting water down over the first section of our field, we pull the plugs from the first barrier, and plug the second barrier. When that section of the field saturates, we move our plugs down to the next area. There can be four or five or even six or seven of these little two inch pipes leading the water in an even flow from the main drain to the irrigation channel. We can irrigate hundreds of trees with very little effort. That's for flat lands.
If we want switching systems, we put in another one of these barriers, and we just pull the plugs and let the water go down. We can direct water around contours, and along to other flat fields. It is a cheap, simple system, consisting of many short lengths of pipe and plugs that you carry with you.
This is not a trickle-flow system. The whole thing is running like blazes. When we need to irrigate, we go up and open our floodgate, and the main water channel comes down and hits that little channel, and we stop it here and it fills up, floods out; then we move on and the next section fills up and floods out, and so on. You let a lot of water go, and you thoroughly soak it. Then you plug the whole thing up by closing down your floodgates.
You can dig those trenches with a little crawler tractor, just a small machine, or you can do it with shovels. The best way to dig a trench with shovels is to use two men. You get a very broad shovel, with one man on it. Around the neck of the shovel, just above the blade, you put a rope, and then you put a toggle on the end of the rope. One man puts the shovel in and the other pulls, and you get a rocking motion up. They can throw up banks about as fast as we can walk, very easily, no arm strain. One man is just moving sideways and putting the shovel in the ground, the other pulls, and away you go. Little Earth banks appear right across the country just like that. If you have to empty a load of gravel and have no dump truck, use that method, with one man standing on the ground pulling, and another just putting the shovel down in the middle. Painless. That is the way the Turks and Afghans contour enormous acreages of very shallow country. They will build and rebuild those contours every year, miles of them, just a couple of men. Ho! Ho! Ab-do!
One of the advantages of the keyline that very few persons see is that if you have a diversion drain above your fields and household systems, that works just as efficiently to remove excess water in winter as it does to direct water into your drains. A well-keylined and combed landscape that has been soil conditioned doesn't get boggy in winter and doesn't get dry in summer. People forget that the same drain that diverts water off the hillside also prevents bog situations and seepage situations below. Once your storages are full and your soil is charged, you can direct a winter runoff into a creek if you want to. You can take it off the landscape through this system, just as easily as putting it on. We often run a descending diversion around the valley slope just to keep the drain bottom dry in winter. The same diversion drain, plugged, will irrigate the valley in summer.
Now when you are wandering around with this diversion drain, bringing it down to your dam, and taking an irrigation canal out of your dam, if you come to a little gully or something, you can easily make a little pond there as you go. It is quite easy to do that.
Another way to go about bringing more water into the landscape, storing water on the land, is to run broad swales. This has a particular application in urban areas. A swale is a critical technology for winter-wet America that is not much used. It is also a very useful technology to use when laying out forests.
You cut shallow blade trenches on true contours, with no movement of water along the trenches. The trenches are quite broad, hardly ever less than four feet wide, and often much wider. You wouldn't do this on a steep slope, just a moderate to shallow slope system. You walk it out along
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