Method and apparatus for the hydrologic regulation of turf soil profiles

Abstract

The hydrology of a "perched water table" soil profile is regulated by installing a simple subsurface air-pipe system in the gravel layer of the soil profile to uniformly control the air pressure under the turf and to adjust the equilibrium condition between the capillary rise and the gravitational forces on the water in the soil. The air pipe system includes perforated pipes extending horizontally through the gravel layer of the soil profile at regular, spaced-apart intervals. The pipes are located adjacent the gravel layer/choker layer interface in vertical alignment with each drain pipe in the water drainpipe trench(es). The pipes are oriented such that the perforations extend along one (or both) sides of the pipe. A vacuum is applied to the pipes and the air is withdrawn uniformly across the gravel layer and the choker layer. According to one aspect of the invention, the air pressure difference across the rootzone acts as an additional force assisting gravity in the extraction of water from the rootzone. According to another aspect of the invention, sub-atmospheric pressure in the gravel layer is provided by the air pipes to increase the driving force of the water through the soil.

Dependencies are inferred from the claim text.