UVM Theses and Dissertations
Format:
Print
Author:
Kominami, Hisashi C.
Dept./Program:
Plant and Soil Science
Year:
2010
Degree:
MS
Abstract:
Three studies of water quality were conducted to investigate the relationship between farming practices and runoff entering Lake Champlain from Shelburne Farms, a 530-ha pasture-based dairy farm along the lakeshore in northwestern Vermont.
In the first study, agricultural runoff and near-shore lake water quality were assessed based on agronomic and water quality data collected on the farm between 2004 and 2008. Water quality monitoring revealed that total phosphorus (TP), dissolved reactive phosphorus (DRP), total suspended solids (TSS), and Escherichia coli concentrations were generally comparable to concentrations reported in agricultural watersheds in which best management practices (BMPs) have been implemented. However, two lake swimming areas frequently violated the Vermont state beach bathing water quality standard after storm events, and diffuse phosphorus pollution is still an environmental problem. Results also demonstrated that dirt roads impair waterways at discrete locations on the farm and that the two strongest contributors to surface water pollution were the dairy barnyard area and catchment draining to Orchard Cove.
For the second study, the site suitability of three existing composting areas was evaluated based on a Natural Resource Conservation Service (NRCS) conservation practice standard. The analysis was performed using a GIS and criteria defined by the NRCS. Results revealed that one composting area is unlikely to pose a threat to water quality. However, the two other composting areas were only partly within suitable areas and may require remedial measures to ensure adequate water quality protection. Additionally, the analysis revealed that one previously used composting area was not properly sited and could potentially have been a source of pollutants to a nearby drainage ditch that discharges into Lake Champlain.
The third study evaluated the start-up performance of the recently built stormwater treatment system at reducing pollutants in agricultural stormwater from the 5-ha dairy barnyard catchment. Between July and December 2009, treatment performance was evaluated by 1) comparing storm flow and non-event flow concentrations of particulate phosphorus (PP), total dissolved phosphorus (TDP), TP, DRP, TSS, and E. coli at the treatment system's inlet and outlet, and 2) quantifying TP and TSS removal efficiencies of a treatment system component (gravel wetland) during two storms. Results demonstrated that mean storm flow concentrations were significantly lower (p <0.05) at the treatment system's outlet for all measured parameters except E. coli. For one storm in mid-November and another in early December, the gravel wetland retained 39 and 13% ofP and 42 and 38% ofTSS, respectively.
Results from these studies suggest that balancing water quality protection and dairy farming may continue to pose challenges at Shelburne Farms despite long-standing BMPs and recent efforts to reduce pollution. However, the results also indicate that implementing additional site-specific BMPs could further reduce agricultural pollution and help Shelburne Farms meet its own stewardship goals. Achieving desired water quality goals for Lake Champlain will probably require better nutrient management and more effective measures to control diffuse pollution from dairy farms.
In the first study, agricultural runoff and near-shore lake water quality were assessed based on agronomic and water quality data collected on the farm between 2004 and 2008. Water quality monitoring revealed that total phosphorus (TP), dissolved reactive phosphorus (DRP), total suspended solids (TSS), and Escherichia coli concentrations were generally comparable to concentrations reported in agricultural watersheds in which best management practices (BMPs) have been implemented. However, two lake swimming areas frequently violated the Vermont state beach bathing water quality standard after storm events, and diffuse phosphorus pollution is still an environmental problem. Results also demonstrated that dirt roads impair waterways at discrete locations on the farm and that the two strongest contributors to surface water pollution were the dairy barnyard area and catchment draining to Orchard Cove.
For the second study, the site suitability of three existing composting areas was evaluated based on a Natural Resource Conservation Service (NRCS) conservation practice standard. The analysis was performed using a GIS and criteria defined by the NRCS. Results revealed that one composting area is unlikely to pose a threat to water quality. However, the two other composting areas were only partly within suitable areas and may require remedial measures to ensure adequate water quality protection. Additionally, the analysis revealed that one previously used composting area was not properly sited and could potentially have been a source of pollutants to a nearby drainage ditch that discharges into Lake Champlain.
The third study evaluated the start-up performance of the recently built stormwater treatment system at reducing pollutants in agricultural stormwater from the 5-ha dairy barnyard catchment. Between July and December 2009, treatment performance was evaluated by 1) comparing storm flow and non-event flow concentrations of particulate phosphorus (PP), total dissolved phosphorus (TDP), TP, DRP, TSS, and E. coli at the treatment system's inlet and outlet, and 2) quantifying TP and TSS removal efficiencies of a treatment system component (gravel wetland) during two storms. Results demonstrated that mean storm flow concentrations were significantly lower (p <0.05) at the treatment system's outlet for all measured parameters except E. coli. For one storm in mid-November and another in early December, the gravel wetland retained 39 and 13% ofP and 42 and 38% ofTSS, respectively.
Results from these studies suggest that balancing water quality protection and dairy farming may continue to pose challenges at Shelburne Farms despite long-standing BMPs and recent efforts to reduce pollution. However, the results also indicate that implementing additional site-specific BMPs could further reduce agricultural pollution and help Shelburne Farms meet its own stewardship goals. Achieving desired water quality goals for Lake Champlain will probably require better nutrient management and more effective measures to control diffuse pollution from dairy farms.