Agenda 11-02-23; 4-a - Resolution Endorsing Consensus Principles II for Revised Falls Lake Rules

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=50 potentially leveraging funding from other sectors. DOT representatives have also indicated an interest in participating in this revised program. Site-Specific Chlorophyll-a Standard and 303(d) Listing Considerations The UNRBA is proposing a path forward in our recommendations that sets an ambitious process toward protecting Falls Lake and for continuing those efforts into the future, but the current standard and 303(d) water quality assessment process should be adjusted to better reflect conditions in Falls Lake. The UNRBA could apply much additional financial resources,time, and effort to secure a new standard through administrative, legislative, or legal means. However,the time associated with these efforts would delay watershed improvement actions and put Falls Lake at risk of water quality degradation that could impact uses. Options include a variance, use-attainability analysis,judicial review, legislative action, or other effort to address the compliance issues. UNRBA membership recommends focusing time and financial resources on collaborative projects that address water quality and watershed health. A request for a site-specific standard may still be needed, and the goal would be to promote progress by setting an achievable goal for the watershed and the lake. The established goal for improving water quality in Falls Lake is the current water quality standard for chlorophyll-a. As part of a comprehensive consideration of an effective nutrient management strategy for Falls Lake, it is appropriate to provide some comments related to this goal. The UNRBA continues to evaluate and consider a site-specific chlorophyll-a standard for Falls Lake. The current standard was adopted in 1979 to address use support issues on the Chowan River. The scientific data, research efforts, and an assessment of uses of Falls Lake shows no use impairment. The current standard is not appropriate for the lake because the designated uses are being met despite exceedances of the criterion in some locations. The 303(d)-assessment methodology being applied is not consistent with scientific evaluations of lake quality in NC or any reservoir environment in similar regions of the US. Even if the UNRBA does not submit a new standard petition as part of this reexamination, the 303(d) assessment methodology should be adjusted for Falls Lake consistent with the science of using chlorophyll-a data to assess overall reservoir quality(how eutrophication is indicated for the reservoir as a whole rather than a station-by-station assessment). The 303(d) assessment methodology for Falls Lake should establish stable and consistent assessment segments based on the physical and limnologic characteristics of the reservoir. On several occasions, the UNRBA has provided comments and requests for an adjusted methodology for Falls Lake. The data and scientific evaluations provide fundamental information about the reservoir and the watershed. The modeling and scenarios demonstrate the limitations of what can be achieved in terms of additional nutrient load reductions and attainment of the chlorophyll-a standard and the amount of time to realize changes given the soil chemistry in the watershed. Because 75 percent of the watershed is unmanaged and significant reductions in nutrient loading have already occurred since the baseline period of the Rules, additional, large-scale nutrient reductions are not likely to occur. Rather than focus on attainment of the chlorophyll-a standard, the goals of the revised strategy should be incremental improvements and long-term protection of the designated uses of Falls Lake. The UNRBA supports an adjusted 303(d) assessment methodology and site-specific chlorophyll-a standard for Falls Lake and will continue to cooperate and collaborate with DEQ-DWR, Environmental Protection Agency (EPA), and other stakeholders on these revisions. Consistent with established legislation,the UNRBA recommends that the NC DEQ-DWR and EMC move forward promptly with the revisions to the Falls Lake Rules taking into consideration these 31