ET from Shallow Groundwater Maintained by Controlled-Drainage/Subirrigation System

by James L. Fouss,
James S. Rogers,

Abstract: Soil-water management by maintaining a shallow groundwater level (watertable) via a dual purpose subdrainage-subirrigation system, is becoming popular in humid regions of the United States and Canada. Controlled-drainage is an important mode of operation for this soil-water management system. Proper and timely control of subsurface drainage effluent can: (a) reduce the need for pumping subirrigation water, (b) prevent overdrainage of the soil profile for more efficient use of naturally occurring rainfall, and (c) reduce the duration of excess soil-water conditions in the root-zone caused by rainfall. This paper presents the results of computer simulations conducted for different water management system designs and for various controlled-watertable depths in the lower Mississippi Valley (LMV) region. Simulation models which have been previously validated from field data for the soils and climate conditions in the LMV region are used, such as DRAINMOD and an enhanced Boussinesq Equation based model which predicts watertable depth fluctuations at multiple modes from the drainline to midway between drains. The predicted potential ET and actual ET from the shallow controlled groundwater are presented for several scenarios. The application of these results in the design and operation of watertable control systems are discussed for the southern humid regions of the United States.

Subject Headings: Soil water | Groundwater | Computer models | Data processing | Simulation models | Systems management | Drainage systems | Groundwater management | North America | United States | Mississippi | Canada

Services: Buy this book/Buy this article


Return to search