Baker Farm Site in Middletown, Ohio

Research Summary

This project investigates groundwater-surface water interactions, focusing on how nutrient transport and water dynamics are influenced by agricultural practices and natural hydrological factors. The study site, located on agricultural land along the Great Miami River in Middletown, Ohio, features alluvial sediments atop low-permeability Ordovician shale, a setting that contributes to extended groundwater residence times. With staple crops grown on the site’s 113 acres, researchers are examining how precipitation and nutrient runoff impact local water quality, particularly concerning nitrogen levels in the aquifer.

Over a 24-week period, researchers collected biweekly surface and groundwater samples from multiple locations, including the Great Miami River, Elk Creek (a tributary), and a man-made lake on the field site. This sampling aims to analyze how water flows through and interacts with these different sources. By examining hydrogen and oxygen stable isotopes in addition to nutrient levels, the study seeks to clarify how local precipitation patterns impact nutrient transport and groundwater recharge.

Preliminary findings from isotope analysis reveal that the man-made lake retains water for extended periods, while the tributary is sensitive to precipitation variations. The study’s results are expected to inform strategies for managing agricultural impact on water resources by enhancing understanding of how surface water contributes to groundwater regimes and how nutrient levels fluctuate with local hydrological changes.

Research Goals and Methods

• Project Focus: Understanding nutrient fate and transport in groundwater-surface water systems in agricultural areas.

• Study Site: Agricultural land along the Great Miami River with alluvial sediments over low-permeability shale, leading to extended groundwater residence times.

• Key Concerns: Nitrogen loading in the aquifer from agricultural runoff and precipitation-driven recharge.

Research Design

• Sample Collection: Biweekly sampling of surface and groundwater over 24 weeks.

  • Sampling locations include:

    • Great Miami River

    • Elk Creek (tributary)

    • Man-made lake on the field site

• Analytical Methods:

  • Hydrogen and oxygen stable isotope analysis to trace water sources.

  • Nitrate and phosphate testing to assess nutrient transport in relation to precipitation.

Preliminary Findings

• Man-Made Lake: Shows prolonged water residence times.

• Elk Creek: Highly sensitive to precipitation patterns.

• Great Miami River: Limited variability in flow, indicating stable regional water sources.

Expected Outcomes

• Improved understanding of nutrient fluxes driven by precipitation.

• Insights into how surface water contributes to groundwater systems in agricultural settings.

• Practical recommendations for crop management to mitigate impacts on local water quality.