The effects of tile drain input on a gaining stream: Using a thermal end member mixing model and a statistical analysis approach Zachary Kisfalusi Master's Thesis Research 10/09/15

Overview Introduction Hypotheses Study Site Methods Results Discussion Conclusions Future Work

Temperature An effective proxy to measure interactions (Baskaran et al., 2009, Stonestrom and Constantz, 2004) Seasonal vs diurnal variations (Silliman and Booth, 1992; Peterson and Sickbert, 2006) Surface water experiences diurnal variations and large seasonal change Near-surface GW is more constant with a muted and lagged effect from seasonal and diurnal alterations

Agricultural setting Large amounts of contaminant runoff from fertilizers Decoupled hydrologic cycle due to tile drains (Sickbert and Peterson, 2014) Tile drain inputs interfere and influence the water chemically and thermally

Hypotheses The thermal input from the tile- drain will have no effect on stream temperature. Though, during low frequency, high magnitude precipitation events, the tile drain input is expected to influence the stream temperature.

Study Site T3 is a semi-natural, low-order gaining stream One known direct tile drain input The reservoirs to be studied: GW aquifer to the east, the tile drain, upstream and downstream of input

Tile diversion zone east of stream for nitrate removal Drains 65 acre farm Larger project to look at tile diversion GW signature from 13 & 15 along with from diversion box

Methods Temperature 150 HOBO Pendant loggers spaced at every 50 cm in stream One logger in each well (2 in riparian and 12 in hyporheic) and 1 in the tile directly Record data every 15 minutes Discharge Velocity measured using a flow meter and the cross-sectional area of stream Taken at 3 locations (Hyporheic wells) Q GW =Q out- Q in- Q tile

Time series Constant groundwater thermal signature Sampling dates visible by spikes Large diurnal changes evident in stream temperature Weather fronts evident Tile is constant throughout summer Noise at end due to composition of diversion box

Stream correlation to tile flow Temperature data from Dec Sept Tile warmer than stream in winter Chaos in spring; 1:1 otherwise Post-diversion has 1:1 ratio within an envelope Suspected tile influence

Conclusions Thermal signature of tile is more constant throughout dataset similar to groundwater Tile drain input does seem to have an effect on the temperature variance of the stream when comparing upstream to downstream between April and early July

Future work Pull data loggers in December Quantify hyporheic exchange, groundwater influence on stream, using HZ temperature loggers Perform a statistical analysis on dataset Interpret full dataset for seasonal changes on stream due to tile flow Determine if mass or variance in temperature play a larger role in the influence of tile drains on streams

Acknowledgements Primary Advisor – Dr. Eric W. Peterson Thesis Committee – Dr. Catherine M. O’Reilly & Dr. Dagmar Budikova Persaud City of Bloomington - Richard Twait Illinois Groundwater Association, Geological Society of America, Illinois State Graduate School, and ISU Department of Geography-Geology Powell Club for financial support Current and past graduate and undergraduate students of Illinois State University for assistance throughout the last year Tamru Taye for assistance in the field, conceptual model, and project collaboration Eileen Maxwell for background data Kelly Sanks and Tyler Rothschild for field support Many others for assistance in the field since December 2014-Present

Thank you for your time. Questions?