Development Of An Agricultural Land Drainage And Reclamation Design Software

Abstract

Good drainage is a pre-requisite for effective soil and water management. In humid areas the removal of excess water is seen as an important aspect of water management, while the provision of drainage in semi-arid irrigated areas is of particular importance to the maintenance of a well aerated root zone and the prevention of the build-up of salinity. The design of appropriate drainage structures however often involves complex hydrological, hydraulic and engineering computations and the use of charts, tables and nomographs, etc. which can lead to errors. In this study an attempt has been made at developing a Windows-based computer programme that facilitates easier and more accurate agricultural land drainage and reclamation design. The Rational formula and
Manning\'s equation were used for surface drainage design whiles Hooghoudt\'s equation was used for subsurface drainage design. The software automatically checks if the design satisfies other requirements as specified in the design code. If the input data are
unable to satisfy both the Rational and Manning\'s equation and other requirements as specified in the code, the software will give suggestions on how to revise the design so that the requirements can be met. The land reclamation component computes leaching
fraction, drainage coefficient, amount of drainable water, salinity, sodicity and then designs a ditch drain to convey the leached water out of the field.

Keywords: Surface and subsurface drainage design, computer application, land reclamation, salinity, sodicity, drains

Journal of the Ghana Institution of Engineers Vol. 5 (1&2) 2007: pp. 39-48