Irrigation and drainage apparatus

摘要

The present invention constitutes an improved subsurface irrigation and drainage apparatus and system for its use that includes at least one main pipe or line arranged to receive a water flow therein that can include a water born fertilizer and, optionally, the main pipe or line can incorporate a fan or like arrangement for injecting an air-flow therein and, as required, an airborn fertilizer. The main line preferably includes spaced cross-pieces that are joined to lateral lines or laterals and may incorporate sleeves therewith, which main line, laterals, and sleeves may contain weirs for maintaining a desired water head therebehind as appropriate, and may include slots, holes or like openings formed therein above and/or below a water line therein. The weirs arranged within the cross-pieces, laterals and sleeves preferably have a triangular shape with the base thereof connected to the lowest surface therein, the sides rising therefrom and sloping inwardly to an apex, which sloping surface facilitates flushing sediment therefrom by introduction of a rapid water flow thereagainst, and each weir can include an arrangement for passing water from a separate source from the flow through the main line, that separate flow passing into the area downstream or in front of the weir as needed, to provide an additional water source thereto. Further, to compensate for any deviation from a desired plane or grade within the drainage system, the present invention provides for inclusion of weirs of different heights wherebehind a desired level of water can be held to effectively and economically provide uniform watering.