PERMACULTURE DESIGN COURSE HANDBOOK
The essential techniques are: • Soil storage (rehabilitation of compressed and/or sealed soils) • Swales (soakage to high groundwater) • Mulch (prevention of evaporation) • Small surface storages (dams and tanks) A. Soil storage: rehabilitation of compressed soils mainly by Keyline methods, including chisel ploughing, for increased soil aeration B. Swales: level grooves to hold water momentarily to keep it from running away rapidly downhill. Water soaks into the ground, and eventually ground slowly charges up with water. Trees planted either side will thrive. Village Homes, Davis, California example of diverting all surface waters into the swales (with 15" rainfall) recharged groundwater supplies to 17 feet in 4 years. C. Mulching: imitation of forest floor - reduces evaporation, prevents erosion, and builds up soil. Easier to achieve in small areas, but can also use 'mulch trees' such as Leucaena, Casuarina, Pines D. Small surface storages: tanks at houses for fresh water supplies; small ponds in gardens, nurseries (for frogs), stock ponds, steep hillside path ends DAMS • Types (saddle, valley, contour, open storage) • Diversion and distribution • Placements T 1.5 FALL
SADDLE DAM
DIVERSION ~ DRAIN TO DAM
, EVAPORATION STRATEGY 2 3
Evaporation Strategy: Make three smaller dams (instead of one big dam), one above the other