Hydrologic response shifts on flat tile drained watersheds

Through the nine years of record for the Little Vermilion River watershed project there are times when the basic hydrologic response of the river shifts unexpectedly. During these shifts, the watershed response differs from what might be called the norm. This response shift is either not detected or poorly described by calibrated models. There are factors then affecting the response of a tile drained watershed that are very important, and going undetected with traditional analyses. This study investigates the correlation of these response shifts with additional data sources, mass interrelationships, and variables previously assumed constant or of low priority. This study using physical data sources and processes may lead to model improvements.