How does agricultural drainage work?

In our Theory of Drainage course, we have been developing an understanding of how agricultural drainage works, both qualitatively and quantitatively. This is exciting, because the some of the same concepts can be applied to wetland hydrology, stream to groundwater table interactions and much more!

We resurrected an old Hele-Shaw laboratory model that was used to investigate some of the equations we applied this semester. With Dr. Skaggs' help, we ran an experiment during class to test the equations. For the most part, resulting data showed a strong agreement between the equations and the lab observations, which were recorded by the graduate students pictured here. We did find some areas where the data began to stray from the predicted values, which was also a valuable exercise.

 

For the study originally published (Skaggs, 1973) from this model, measurements were observed manually using optical sights. Today, it would be a great way to apply vision-based liquid level measurement!

SKAGGS, R (1973). "WATER TABLE MOVEMENT DURING SUBIRRIGATION". Transactions of the ASAE(0001-2351), 16 (5), p. 988.