Findings & Recommendations
  1. The study was competently executed and the results were generally supported by the peer reviews. We believe the results are valid although limitations on the P source estimations have to be taken into account as previously discussed. The study results should be put to use by resource management agencies in the Missisquoi Bay watershed.
     
  2. The project has brought the scientific capability in Vermont up to a comparable level to what exists in Québec with respect to watershed modeling and critical source area analysis in the Missisquoi Bay watershed. Complementary research in the Québec portion of the watershed arrived at similar conclusions regarding the high percentage of the phosphorus load that is coming from a small percentage of the land area.
     
  3. The United States Department of Agriculture (USDA) should make sure that state Natural Resource Conservation Service (NRCS) offices retain the flexibility to apply local ranking criteria that give high weight to sites having critical source area characteristics when making funding decisions for applications under EQIP and other programs. National standards for ranking criteria should not be imposed in a way that limits the ability of local offices to target critical source areas. The need to make maximum use of the available dollars to reduce phosphorus loading to Missisquoi Bay should outweigh concerns about inequities in funding allocations when applying a critical source area targeting approach.
     
  4. Critical source area targeting should be implemented at two spatial scales:
    • Sub-watershed scale: Separate Environmental Quality Incentive Program (EQIP) funding pools should be established for areas identified as critical sub-watersheds, as has been done for the Rock River and Lewis Creek watersheds in Vermont.
    • Farm scale: Ranking of funding applications should be based on site physical characteristics (e.g., slope, topographic index, soil group, proximity to water) available from this study and accurate site information on land use and cropping patterns, management practices in place, and soil phosphorus tests (STP) obtained by field surveys. Resource management agencies should be proactive in their outreach, targeting landowners where potential critical source areas have been identified by this study, rather than passively responding to applications for funding.
       
  5. More management attention should be paid to reducing phosphorus loads from streambank erosion caused by channel disequilibrium, since this process represents a high percentage of the phosphorus load delivered to the Missisquoi River.  Resource management must promote strategies to regain and maintain the stream channel’s equilibrium conditions, such as the restoration of a channel’s access to the floodplain and the restoration of a stable slope and planform, in order to achieve phosphorus load reductions over the long term.
     
  6. The long-term goal of state and federal resource management agencies should be to limit or mitigate the effects of intensive cropping and animal use in critical source areas. This should be accomplished by educational outreach and technical assistance, financial incentives for mitigating practices such as cover cropping, multi-crop grain rotations, changes in tilling practices, and conservation buffers, and a structure of those incentives to place greater value on the areas that pose the greatest risk of export. Stronger regulatory approaches should be used where voluntary incentives are not working or are not being applied on the critical source areas. It is likely that much of these efforts will need to be focused on small farms in Vermont since medium and large farms already fall under higher levels of state water quality regulation.
     
  7. The maps and other supporting GIS data files from this study should be made available to resource management agencies in the basin for placement on agency computer servers and at the Vermont Center for Geographic Information. Field staff should make use of these files to prioritize site visits and to support more in-depth farm assessments at the field and sub-field levels. Field tablet technology under development by NRCS to support on-site BMP analysis and scenario testing with farmers should incorporate the critical source area data produced by this study. Public notice should be provided before critical source areas maps are made broadly available so that landowners are not caught by surprise and appropriate disclaimers about the limitations of the analysis should be included.
     
  8. The Partner Liaison position established under the President’s America’s Great Outdoors Initiative in Vermont will support coordination among water quality management agencies in implementing an agricultural-based critical source area targeting approach in the Lake Champlain Basin. Funding for this new position should be sustained in the future.
     
  9. Tactical basin plans developed as part of the Vermont Surface Water Management Strategy should incorporate the findings of this analysis into their priorities.
     
  10. The newly revised USDA national conservation practice standard on nutrient management in order to help producers better manage the application of nutrients on agricultural land should be used in priority in the Missisquoi Bay Basin as it has shown significant results in other watersheds such as the Upper Mississippi Basin, the Chesapeake Bay Watershed and the Great Lakes Basin. The nutrient management standard provides a roadmap for NRCS staff and others to help producers apply available nutrient sources in the right amount, from the right source, in the right place, at the right time for maximum agricultural and environmental benefits: http://www.nrcs.usda.gov/wps/portal/nrcs/main/national/landuse/crops/npm
     
  11. There is a need for further research on the relationship between soil P concentrations (STP) and P concentrations in field runoff for Missisquoi Bay Basin agricultural soils to better rank critical source areas in terms of risk of soil P desorption (soil P release in runoff).
     
  12. Vermont AAFM should compile and retain soil phosphorus concentration data available from farm nutrient management plans and other sources in a database for use in making more accurate critical source area assessments. These data could be aggregated if necessary to preserve farmer confidentiality.
     
  13. The IJC has made valuable contributions to phosphorus and water quality management in Missisquoi Bay in recent years through involvement in the causeway issue, support for small farm nutrient management planning, and the present critical source area analysis. Future involvement by the IJC in specific study issues such as these would be very welcome. The Missisquoi Study Board has considered the topic of future involvement by the IJC at a broader oversight level for the Lake Champlain Basin. We have concluded that broad IJC oversight is not warranted because of the strong bilateral presence of the Lake Champlain Basin Program. Through the existing MOU between Vermont, Québec, and New York, and the involvement of US and Provincial partners on the Lake Champlain Basin Program's Steering Committee, considerable coordination and collaboration between partners and across the border regularly occur. We feel that adding a permanent monitoring board to this existing structure would be redundant.
     
  14. The critical source area modeling approach is fundamentally sound, particularly when used over the short term, and should be applied throughout the Lake Champlain Basin, in Vermont, New York, and Québec. Development of supporting data and refinements of the methods to better address developed land and in-stream sources will be needed in applying the approach to other watersheds. Nevertheless, water quality improvements from long-term critical source area management remain difficult to estimate due to spatial complexity and variability of large watershed systems.