A study published in the Wetlands science journal examined the long-term impact of the Coldwater Creek Restored Wetland on water quality within the Grand Lake St. Marys watershed. Here are highlights from the study, which was conducted by Wright State University-Lake Campus Biology Professor Dr. Stephen Jacquemin, Research Assistant Morgan Grunden, and Mercer County Agriculture & Natural Resource Director Theresa Dirksen.
- Between 2017 and 2023, researchers monitored the wetland’s ability to filter nutrients and sediments from agricultural runoff, a significant contributor to Grand Lake’s harmful algal blooms
- The findings reveal that the wetland intercepted approximately 10.5 million cubic meters of water, accounting for about 10% of the subwatershed’s total flow into Grand Lake St. Marys
- Notably, the wetland achieved average load reductions of at least 63% for soluble reactive phosphorus (1.85 g/m²/year), total phosphorus (5.2 g/m²/year), nitrate-nitrogen (48 g/m²/year), and total suspended solids (657 g/m²/year)
- These results underscore the critical role of restored wetlands in mitigating nutrient pollution and highlight the necessity of long-term monitoring to fully understand and enhance their ecological functions