07/01/2017 - 06/30/2019
- Catherine Christenson, University of Wisconsin-Madison
- Michael Cardiff, University of Wisconsin-Madison
- David J. Hart, University of Wisconsin - Extension
- Susan K. Swanson, Beloit College
Groundwater discharge to surface water carries unique thermal and geochemical signatures and provides important ecological services by providing baseflow and stable temperature habitats (Hayashi and Rosenberry, 2002). GW-SW interactions have proven to be highly variable at a local scale (Shaw and Prepas, 1990). Dense spatial variability is rarelydocumented with water-quality sensor technology due to cost, software, and power limitations. In a warming climate (Cook et al., 2013), environmental scientists will need additional tools to measure hydrologic data to understand and model complex environmental systems (Lovett et al., 2007; Tauro et al., 2018).Currently, hydrologic properties in streams are most commonly measured at in-situ “point-scale” locations, sometimes continuously through time. Data from fixed stations provide information that are often used to characterize the cumulative upstream watershed (Gilliom et. al, 1995). Water-quality sensors that are used to collect continuous data at fixed stations are frequently purchased as a pre-compiled package with software, and are cost prohibitive. However, recent advances in low-cost, easy-to-use microcontrollers have made customizing sensor software as a scientific tool highly accessible (Wickert et al., 2014). To overcome these issues of spatial heterogeneity and cost, we developed a method that collects spatially dense datasets of water-quality and streambed conductivity over lengths of streams and lakes via canoe utilizing low-cost microcontrollers. Parameters collected included stream temperature, dissolved oxygen content, pH, specific conductance, and nitrate and chloride concentrations in stream water, in combination with streambed electrical conductivity, water depth, and video data in order to create a synoptic view of a stream’s quality and areas of groundwater-surface water exchange. The purpose of this study is to develop, validate and assess the utility of collecting high-density, geolocated data on small surface-water systems.