DIN 1185-1:2015-12

Drainage eliminates soil moisture that is harmful to crops and tillage, improves soil aeration, opens up deeper soil areas for plant roots, makes better use of nutrients, breaks down organic acids, and stimulates the activity of soil bacteria. The possibility of earlier tillage extends the growing season. Management is facilitated and damage associated with mechanization (soil compaction) is reduced or eliminated. Pastures become more treadable, and precipitation during the growing season can be better utilized. Due to the increased storage capacity, waterlogged soils and soils characterized by retained water in particular have considerably more usable soil moisture after drainage during dry periods. The technical systems for drainage can only be properly and economically constructed and maintained if they are based on a design that has been drawn up in accordance with recognized technical principles. The soil water regime is differentiated according to soil wetted by groundwater, waterlogged or characterized by retained water. Recognizing that it is more successful to address the cause rather than the effect, the site assessment for drainage will therefore be the basis for the choice of technical measure. Improvement of the soil structure as far as possible and its stabilization is regarded as the essential goal of drainage. The DIN working committee "Irrigation and Drainage" has set itself the goal of modernizing and streamlining the standard, incorporating the latest findings, dispensing with the details that are now established in other standards (for example, pedological data), and replacing the textbook-like form of the standard as far as possible with a practical design. In accordance with these work instructions it seemed expedient to restructure the DIN 1185 series of standards and to summarize them in only three parts so that the person in charge or the site manager is given the opportunity to obtain general or specific information on the various issues and technical details, depending on knowledge and experience, without having to consult or work through the entire standard. Part 1 "General principles" therefore contains, with special consideration of the newly included subsoil amelioration, an overview of the current possibilities of regulating the soil water regime, taking into account the specific site conditions. It was considered expedient to subordinate all technical possibilities to the generic term "drainage". Special cases are also dealt with in this part.