Managing water excess and deficit in agriculture: subsurface drainage and irrigation systems

Water is essential in our daily lives: for nature, agriculture, drinking water, and industry. However, the demand for freshwater is increasing while the availability is declining. In addition, climate change is increasingly causing extreme weather conditions, such as droughts and heavy rainfall.

To anticipate both dry and wet conditions in agriculture is therefore becoming increasingly important. One measure is to convert existing subsurface drainage systems into controlled drainage with subirrigation (CDSI). CDSI aims to drain groundwater when necessary, retain water when possible, and supply water where feasible.

In my PhD research, I investigated the hydrological opportunities of CDSI in the Dutch Pleistocene uplands. CDSI can raise groundwater levels and thereby increase crop yields. In the short term, it is relatively easy to convert existing drainage systems into CDSI. In the long term, CDSI can serve as a technical measure in areas where soil and water were leading in spatial planning, to mitigate both too wet and too dry circumstances.