STIBINGER J.
Abstract
Policy of subsurface pipe drainage practices in agricultural areas situated around Nile Delta in Egypt was analyzed. Subsurface
drainage structures were designed for the conditions of steady state drainage fl ow. This work shows procedures based
on non-steady state drainage fl ow in the agricultural areas in Nile Delta, developed by irrigation and drainage. For research
of non-steady state drainage fl ow analytical solution of Boussinesq’s equation was used. The fi nal expression of lowering
of water table in time was approximated by Glover-Dumm. The objective of this article is to explain the hydraulic function
of subsurface pipe drainage system on agricultural experimental fi eld in Mashtul Pilot Area (Nile Delta) also in non-steady
state drainage fl ow conditions. The solution of the drainage project in Nile Delta was applied in other irrigated agricultural
areas in semi-arid and arid regions and can serve as a good tool for the future. In order to mitigate soil salinity a drainage
system was designed for the conditions of steady-state drainage fl ow. However, in reality non-steady-state drainage situations
prevail, and a model to solve the problem is presented.
Key words:
subsurface drainage systems, agricultural areas, Mashtul Pilot Area, Nile Delta, Egypt, equations of non-steady
state drainage fl ow, water table