Install swales on contour in locations as determined by survey and site evaluation.
Create a berm on contour with material borrowed adjacent to berm on uphill side. The borrow site will create a slight depression which will hold water in rain events sufficient to produce runoff. Create one or more spillways on berm to allow for excess water movement during flood events. Create one or more wetland areas behind berm by applying clay, impervious liner material or dispersal agents to perch a water table and overfilling with topsoil.
Central Texas has lost a significant amount of topsoil due to erosion and eradication of Beaver populations since European settlement in the 1800’s. One result of this is that much rainfall quickly runs off the land carrying with it more soil and the detritus on the ground that would build new topsoil. The building of swales is one of the most efficient and cost effective methods of capturing more of the rain falling on a watershed resulting in numerous benefits.
• Increase of water insoak along entire length of swale. This increase can be over 10 times previous amounts.
• Harvest of erosion materials behind swale for rapid buildup of topsoil and resultant fertility.
• Ability to redirect rainwater to recharge wetlands, ponds aquifers or other insoak fields.
• Ability to redirect heavy rainwater away from sensitive areas such as erodable slopes or various improvements.
• Plant beneficial and useful plants including wildlife food plants without supplemental water.
• Create seed factories that will naturally reseed adjacent areas.
• Reduce erosion
When swales are built in conjunction with soil remineralization, inoculation of beneficial soil microorganisms and native plant revegitation, the positive results are exponential. The natural process of topsoil generation is greatly accelerated. One reason for this is that soil organisms (especially bacteria and fungi) create the soil crumb structure that holds water, envites earthworms and soil macroarthropods and allows easy root, water and air penetration. These organisms only reproduce and do their work during a window of optimum moisture. In Central Texas and numerous places throughout the world with poor thin soils this window is very narrow. In the area in and adjacent to swales this window is dramatically increased. Therefore fertility increases rapidly along swales with the resulting increase in quality and quantity of biomass. This biomass is food and shelter for wildlife of all kinds.
The water captured in swale systems follows several natural pathways. Some portion will soak into the soil with a filtering action and recharge the aquifer with the highest quality water. Other portions will soak into the soil and follow seep pathways to arrive in creeks and drainages over a protracted period of time, all the while providing water to the entire area downhill from the swale. Another portion will be used by the plants and soil building organisms that inhabit the swale. Some part of this water is stored in the greater biomass generated and another part will be transpired into the atmosphere to fall as rain on some other property along with natural evaporation. All these beneficial uses come from water that would have otherwise contributed to flood waters downstream with their load of eroded soil, leaf litter and all the accompanying flood problems.
Place dead barriers in areas with slope greater than 3%.
The procedure involves laying branches and small logs on contour. Select branches that are straight in one plane of the branch or log and work it into the leaf litter such that it makes contact with the soil as much as possible. Alternately, use a pick or hoe to remove leaf litter under branch and work it into the soil somewhat. (Best method) Several lengths of branches can be placed end to end.
In conjunction with placing dead barriers it is desirable to spread some remineralization mix (a shovel full for a four-foot branch). As this area will collect more moisture and hold it longer, it is an excellent place to add seed. One technique is to add seed to the amount of remineralization mix you intend to use that day and spread together. When seed is planted it is helpful to place some brush over the area to prevent deer an other animals from browsing the young seedlings. Be careful not to apply so much as to block out light even in a deep forest shade.
Over time the dead barrier will build and be colonized with plant roots and fungal hyphae and become even more stable. Another layer of dead barrier can then be placed above the mature one and slightly uphill. At this point the process of soil building in the area begins to greatly accelerate.
On slopes the main mechanism for erosion is sheet flow of water in heavy rain events. This water carries leaf litter, soil, small twigs, animal droppings and all manner of potential soil building materials downhill and ultimately into streams and rivers. If this material encounters an obstruction it will gather behind it. Creating a long obstruction such as a dead barrier also slows water and allows more water to soak into the soil at that location. The presence of the branch and leaf litter retards evaporation and therefore the area stays moist much longer than surrounding areas. This is an ideal habitat for soil organisms to take hold and proliferate; building soil at greatly accelerated rates compared to surrounding areas. This also is the preferred habitat for many insects and their larva. All insect eating wildlife benefit from this increase in biodiversity and carrying capacity. Beetles are especially fond of this habitat and over time Wild Turkey will discover this fertile hunting ground of their favorite food.
Create exclosures to allow the successful establishment of sensitive plants introduced by seeding, starter plants, as well as allowing the regrowth of plants through natural ecological succession.
Use any of available deer/game fencing materials to create an area deer or stock animals cannot get into. Area of exclosure can be any size and take any shape. Include gate for easy access.
Use brush to create a windrow fence. The brush can be the entire length of the structure or used in conjunction with any of the fencing referenced above. An option is to build sections of the exclosure on top of, or in proximity to a permaculture swale. The added water availability will allow the planting of a larger variety of plants and vines on these windrows.
One of the major reasons for the paucity of biological diversity in Central Texas today as opposed to pre-European settlement, is the pressure from deer and livestock grazing and browsing. Young plants are especially sensitive to this pressure and as a result many species that would naturally reseed themselves cannot become established. An exclosure, by restricting this pressure, will allow many native plants to survive through their young vulnerable stage. In 5 to 10 years the exclosures can be removed. This technique is one of the least expensive and effective methods of reestablishing some of the most beneficial plants for healthy wildlife populations of all kinds. When used in conjunction with Permaculture Swales, scientific remineralization and compost teas, vibrant regrowth occurs. This new growth is more nutrient dense than surrounding vegitation. Songbirds and other wildlife recognize this and flock to the area bringing with them native seeds they have eaten in the bioregion. All this working together creates and ongoing passive natural reseeding process which continues without any additional input on your part, for years into the future.
Gabions are any structures which slow down water flow in a seasonal stream bed or other drainage channel. The classic design is a wire basket tube of rocks placed across a drainage channel. In fact, the imagination is the only limit to gabion design from a fabricated log jam to a stone and mortar check dam. Seeds, plants, soil and soil organisms can be added above these structures to quickly rebuild biodiversity and augment the structure.
As water moves with greater speed its carrying capacity increases as well a destructive and erosive force. Any strategy to slow down water will reduce adverse effects as well as drop out sediments to build topsoil and fertility behind the structure. With the presence of gabions more water soaks into the soil and creeks begin to flow longer after rains. Selective pruning above gabions let in more light and allow a faculative wetland community of plants to establish increasing function and durability while augmenting the wildlife carrying capacity of the land.
Apply remineralization mix to selected areas.
Design remineralization mix according to soil test results. Add recommended minerals and nutrients to compost mix. Best results accrue after twenty-one day biofermentation period. Product can then be applied in selected areas such as areas to be seeded or planted, around trees, on future Permaculture swale and exclosure sites etc.
Apply Compost Tea to selected areas.
Formulate Compost Tea and apply as soil spray in locations as above and as a foliar spray to introduced and existing plants.