Fellow: Mohammed Mizanur Rahman, Agricultural and Biosystems Engineering, NDSU
Advisor: Zhulu Lin, Assistant Professor, Department of Agricultural and Biosystems Engineering, North Dakota State University, Fargo, ND.
Matching Support: NDSU
Degree Progress: I anticipate graduating in December 2011

The Red River of the North Basin (RRNB) has been following a wet weather pattern since 1993. Farmers in the region have been experiencing wetter than normal working conditions and increasing soil salinity problems in their lands. Installation of subsurface (or tile) drainage systems helps to drain excess water to improve field conditions and to lower water table to mitigate dryland salinity problems. On the other hand, due to the recent wet weather cycle, the residents along the river have also witnessed more frequent major floods occurring in the Red River. In the century-long stream stage history, five out of the ten highest historic crests in the Red River at Fargo, occurred in the past 15 years. At the field scale, it is well known that the subsurface drainage systems may increase (subsurface) runoff volume from the tiled fields. However, it is less well known how the subsurface drainage will affect the streamflows downstream at the basin scale. The purpose of the study is to apply the Soil and Water Assessment Tool (SWAT), a physically-based watershed model, to analyze the impact of the subsurface drainage on the streamflows in the upper Red River basin.

Project Objectives:

The main objective of the study is to apply the SWAT model to investigate the effects of subsurface drainage on streamflows in the upper Red River basin. The specific objectives are:

1. To develop and calibrate the SWAT model for the upper Red River of the North basin.
2. To develop a practical method for mapping the existing tile-drained areas in the upper Red River basin.
3. To conduct the impact analysis of tile drainage on streamflows in the upper Red River basin during summer and spring seasons.

Progress:

I have finished collecting and processing data for the RRNB on topography, land use, soils, meteorology, hydrology, and water quality. I have successfully set up and calibrated the SWAT model for the Western Wild Rice River watershed. I am developing a method for mapping the existing tile-drained areas in the upper Red River basin.

Significance:

Whether the increasing trend of the tile drainage installation in the Red River Valley will further increase the chances of spring flood in the area or mitigate the current situation of spring flooding is an issue on debate. On one hand, it is believed that subsurface drainage systems normally promote drainage from the waterlogged root zone of agricultural lands. On the other hand, the field studies in the area have shown that the tile drainage reduces the soil moisture in the fall season. In turn, the lowered soil moisture level in the region’s soils may decrease runoff volumes during the snow-melting season in spring. The calibrated SWAT model will help in understanding the hydrologic cycle and the impact of the tile drainage on streamflows in the RRNB. The model is also expected to be used in developing a long term regional water resources management plan.

Peer-Reviewed Journal Papers:

     Lin, Z., A.P. Kirilenko, and M.M. Rahman (2011). Copying with uncertainty in assessing climate change impacts on streamflows. Proceedings of the AWRA 2011 Spring Specialty Conference, Baltimore, MD (submitted).

     Rahman, M.M., and Z. Lin (2011). Hydrologic adaptation of SWAT model to analyze impacts of tile drainage on streamflows in snow dominated upper Red River of the North Basin. ASABE Annual International Meeting 2011, Louisville, KY (Abstract accepted).