Presented by: Bill Kreutzberger Jaime Robinson November 14, 2017 Science and Stakeholders - Taking Initiative in the High Rock Lake Nutrient Management Strategy Presented by: Bill Kreutzberger Jaime Robinson November 14, 2017 Abbotts Creek, a section of High Rock Lake near Lexington, North Carolina. Source: Photo by Panda Brown. (Wife of en:User:Pharmboy)

Science and Stakeholders The Science: NC Division of Environmental Quality’s Nutrient Criteria Development Plan High Rock Lake selected as the first lake for nutrient management The Stakeholders Yadkin-Pee Dee River Basin Association, including POTWs and industry Yadkin RiverKeeper Agricultural Interests NCDOT Stormwater programs Potential Outcomes and Strategy Moving Forward

The Need for a Strategy

NCDP Background Refresher Three areas for Nutrient Criteria Development Piedmont Reservoir watershed High Rock Lake Planned adoption of numerical nutrient criteria (NNC) completion in July 2018 Estuaries Albemarle Sound Planned adoption of NNC by Dec 2020 Rivers/Streams Central Portion of Cape Fear River Basin Planned adoption of NNC by Dec 2021 Statewide Criteria Estuaries – 2023 Lakes – 2024 Rivers/streams – 2025

NCDP Background Refresher Creates Science Advisory Council (SAC) and Criteria Implementation Committee (CIC) SAC focus has been primarily on HRL

YPDRBA Engagement in NCDP Process

YPDRBA Engagement in the NCDP Mission Statement: Through active participation in the High Rock Lake Nutrient Criteria Development, we will work collectively to engage with DEQ and other stakeholders such that it results in comprehensive, cost-effective, flexible, and adaptive process and requirements

Science and Stakeholders Why engage early in the process? Water Quality in HRL NPDES Permit Cycles NCDP Other Stakeholder Objectives

Science and Stakeholders Why engage early in the process? Water Quality in HRL NPDES Permit Cycles NCDP Other Stakeholder Objectives

Comprehensive Approach: Understanding the Source Contributions of Nutrients Point Sources are not the only major contributor of nutrients

YPDRBA Engagement in the NCDP Implementing the Mission Statement DEQ engagement Active participation in SAC and CIC process, including technical reviews Stakeholder engagement Alliance with Yadkin Riverkeeper and outreach to agricultural interests and NCDOT Comprehensive approach Working with Riverkeeper on approach to not leave responsibility just on point source discharges Cost-effective approach Creation of nutrient removal cost estimation tool for point-sources and use of water quality model to develop cost-effective nutrient reduction strategy Flexible and adaptive process Supporting proposed revisions to chlorophyll a water quality and conducting water quality sampling at 2 HRL stations to develop baseline WQ dataset

The Science: Chlorophyll a response Modeling indicates phosphorus removal only will lead to reductions of chlorophyll a in HRL and meet water quality objectives. We also know from evaluating WWTP processes that this is more cost-effective; TN removal leads to a large jump in cost.

The Science: Chlorophyll a response How much TP removal by point source discharges is enough? This depends on how much is also reduced from nonpoint sources. Reductions only by the point sources could be enough to meet the standard, but prefer a watershed-scale approach to nutrient management Potential changes to the chlorophyll a standard could provide some flexibility in how the standard is achieved and applied to utilities

The Science: Phosphorus Removal Costs and Responses Geomean Chl a (µg/L)1 Scenario TP Reduction Total Capital Total Annual O&M Total Net Present Value Point Source Reductions All Source Reductions Baseline N/A 43.7 - 32.6 Current 11% 42.6 - 31.7 39.1 - 29.0 1 mg/L at permitted flow 44% $8,348,000 $1,799,100 $28,985,000 39.5 - 29.3 26.3 - 19.1 1 mg/L at 80% permitted flow 55% $28,536,000 38.4 - 28.5 21.8 - 15.6 0.5 mg/L at 80% permitted flow 78% $42,842,000 $4,057,100 $89,375,000 36.3 - 26.8 12.9 - 8.7 Notes: Assumes TN loading at baseline conditions for all scenarios Costs updated to 10/2016 based on ENR CCI

The Science: Nitrogen Removal Costs and Responses Nitrification Nitrogen Removal Scenario TN Change (+ Increase, - Decrease) Total Capital Total Annual O&M Total Net Present Value Baseline Current +21% 8 mg/L at permitted flow +11% $78,585,000 $5,469,300 $186,434,000 $4,312,900 $377,220,000 5 mg/L at permitted flow -31% $288,193,000 $7,547,000 $516,074,000 Note: Costs updated to 10/2016 based on ENR CCI

Potential range of required reduction based on geometric mean results You can say that we are going to present results based on seasonal geomean - like discussion from SAC- but minor changes to curves

Science and Stakeholders: Chlorophyll a response Scenario 1 – All sources (56%) Scenario 2 – All sources (45%) Scenario 3 – All sources (22%) Scenario 1 – Point sources only (89%) Scenario 3 – Point sources only (81%) Scenario 2 – Point sources only (87%) Current – Point sources only (97%)

Potential Outcomes and Strategy Moving Forward

Stakeholder Engagement YPDRBA in conjunction with stakeholders develop initial nutrient management strategy Move forward with P-only nutrient reduction strategy for dischargers Develop non-regulatory approach to N reductions Determine appropriate targets for P reduction understanding limitations of the model Work with other stakeholders to reach agreement on initial reduction goals and strategies Track SAC process to ensure strategy is consistent with proposed criteria Continue to use the Cost Curve to understand implications of TP removal on utilities Propose strategy to DWR and EMC

The Benefits of Stakeholder Engagement Understanding the other sources of nutrient loading and the potential costs of nutrient reduction enables the YPDRBA and its members to make choices about where to make investment. City of Winston-Salem: Provides funding support to its Soil and Water Conservation Service staff to reduce nutrient loading through agricultural programs and education efforts. This type of support is being considered across the basin because it is more cost- effective than the same amount of point-source removal.

The Science: Preparing for an Adaptive Management Process Began seasonal monitoring of High Rock Lake DEQ only monitors every 5 years Increased frequency needed to detect trends Objective: As nutrient management strategies are implemented, water quality will be monitored and benefits recognized Chlorophyll a Dissolved Oxygen pH

Science and Stakeholders: Preparing for an Adaptive Management Process Two stations are now monitored by the YPDRBA. Utilities are cooperating to provide sampling support and analysis is done in part by the same lab performing their required monthly ambient monitoring. DEQ hosted a sampling event in the lake Boats provided by DEQ and the Yadkin RiverKeeper SAC members, YPDRBA members, and the RiverKeeper were invited

The Science – DO and pH Dissolved Oxygen pH Consensus that SAC should not recommend changes to the DO criterion magnitude, nor derive separate criteria for bottom waters SAC discussed refining narrative language on where and how DO criteria are applied Discussed clarification for bottom waters hypoxia and temporary surface water hypoxia due to mixing Decided that the existing language was sufficient for lake bottom waters, and hypoxia in lake surface waters was too rare to merit additional language. pH Further discussed proposal to increase pH maximum to 9.5 (from 9.0) Considerable debate and presentation of data – including examination of ammonia levels Asked SAC members to develop proposals for July meeting

Science and Stakeholders: Strategy Moving Forward YPDRBA in conjunction with stakeholders develop initial nutrient management strategy Utilities Actions: Move forward with P-only nutrient reduction strategy for dischargers and carry this forward in permitting renewal strategies Continue to use the Cost Curve to understand implications of TP removal on utilities Winston-Salem’s continued support of Soil and Water Conservation District staffing Track and participate in SAC process to ensure strategy is consistent with proposed criteria Stakeholders Actions: Develop non-regulatory approach to N reductions with other stakeholders Joint meeting of stakeholders – August-October * *Timing based on SAC recommendations regarding chlorophyll a and algal toxins

YPDRBA Plan Moving Forward Pause for recommendations from the SAC Further stakeholder engagement meetings to develop strategy Initial nutrient management strategy Winston-Salem’s continued support of Soil and Water Conservation District staffing Consider expansion of this approach to other HRL watershed counties with YPDRBA funding Promotion of land use best management practices HRL monitoring to support an adaptive management strategy

Science and Stakeholders: A Model for Success

High Rock Lake Dischargers Mission Statement Through active participation in the High Rock Lake Nutrient Criteria Development, we will work collectively to engage with DEQ and other stakeholders such that it results in comprehensive, cost-effective, flexible, and adaptive process and requirements.

YPDRBA Engagement in the NCDP Implementing the Mission Statement to achieve objectives DEQ engagement Active participation in SAC and CIC process, including technical reviews Stakeholder engagement Alliance with Yadkin Riverkeeper and outreach to agricultural interests and NCDOT Comprehensive approach Working with Riverkeeper on approach to not leave responsibility just on point source discharges Cost-effective approach Creation of nutrient removal cost estimation tool for point-sources and use of water quality model to develop cost-effective nutrient reduction strategy Flexible and adaptive process Supporting proposed revisions to chlorophyll a water quality standard and conducting water quality sampling at 2 HRL stations to develop baseline WQ dataset

Presented by: Bill Kreutzberger Jaime Robinson November 14, 2017 Science and Stakeholders - Taking Initiative in the High Rock Lake Nutrient Management Strategy Presented by: Bill Kreutzberger Jaime Robinson November 14, 2017 Abbotts Creek, a section of High Rock Lake near Lexington, North Carolina. Source: Photo by Panda Brown. (Wife of en:User:Pharmboy)