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HomeMy WebLinkAboutAppendix-D_ Low_Inflow_Protocol_CatawbaAppendix D Low Inflow Protocol for the Catawba River Basin Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 1 January 24, 2006 Attachment G - Low Inflow Protocol (LIP) for the Catawba-Wateree Project PURPOSE The purpose of this Low Inflow Protocol (LIP) is to establish procedures for reductions in water use during periods of low inflow to the Catawba-Wateree Project (the Project). The LIP was developed on the basis that all parties with interests in water quantity will share the responsibility to establish priorities and to conserve the limited water supply. OVERVIEW This Low Inflow Protocol provides trigger points and procedures for how the Catawba-Wateree Project will be operated by the Licensee, as well as water withdrawal reduction measures and goals for other water users during periods of low inflow (i.e., periods when there is not enough water flowing into the Project reservoirs to meet the normal water demands while maintaining Remaining Usable Storage in the reservoir system at or above a seasonal target level). The Licensee will provide flow from hydro generation and other means to support electric customer needs and the instream flow needs of the Project. During periods of normal inflow, reservoir levels will be maintained within prescribed Normal Operating Ranges. During times that inflow is not adequate to meet all of the normal demands for water and maintain reservoir levels as normally targeted, the Licensee will progressively reduce hydro generation. If hydrologic conditions worsen until trigger points outlined herein are reached, the Licensee will declare a Stage 0 - Low Inflow Watch and begin meeting with the applicable agencies and water users to discuss this LIP. If hydrologic conditions continue to worsen, the Licensee will declare various stages of a Low Inflow Condition (LIC-as defined in the Procedure section of this document). Each progressive stage of the LIC will call for greater reductions in hydro station releases and water withdrawals, and allow additional use of the available water storage inventory. The goal of this staged Low Inflow Protocol is to take the actions needed in the Catawba- Wateree River Basin to delay the point at which the Project’s available water storage inventory is fully depleted. While there are no human actions that can guarantee that the Catawba- Wateree River Basin will never experience operability limitations at water intake structures due to low reservoir levels or low streamflows, this Low Inflow Protocol is intended to provide additional time to allow precipitation to restore streamflow, reservoir levels, and groundwater levels to normal ranges. The amount of additional time that is gained during the LIP depends primarily on the diagnostic accuracy of the trigger points, the amount of regulatory flexibility the Licensee has to operate the Project, and the effectiveness of the Licensee and the water users in working together to implement their required actions and achieve significant water use reductions. In order to ensure continuous improvement regarding the LIP and its implementation throughout the term of the New License, the LIP will be re-evaluated and modified periodically. These re- evaluations and modifications will be as determined by the Catawba-Wateree Drought Management Advisory Group (CW-DMAG). Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 2 January 24, 2006 KEY FACTS AND DEFINITIONS 1. Full Pond Elevation – Also referred to simply as “full pond”, this is the level of a reservoir that corresponds to the point at which water would first begin to spill from the reservoir’s dam(s) if the Licensee took no action. This level corresponds to the lowest point along the top of the spillway (including flashboards) for reservoirs without flood gates, and to the lowest point along the top of the flood gates for reservoirs that do have flood gates. To avoid confusion among the many reservoirs the Licensee operates, the Licensee has adopted the practice of referring to the Full Pond Elevation for all of its reservoirs as equal to 100.0-feet (ft.) relative. The Full Pond Elevations for the Catawba-Wateree Project reservoirs are as follows: Reservoir Full Pond Elevation (ft. above Mean Sea Level) Lake James 1200.0 Lake Rhodhiss 995.1 Lake Hickory 935.0 Lookout Shoals Lake 838.1 Lake Norman 760.0 Mountain Island Lake 647.5 Lake Wylie 569.4 Fishing Creek Reservoir 417.2 Great Falls-Dearborn Reservoir 355.8 Cedar Creek Reservoir 284.4 Lake Wateree 225.5 2. Net Inflow – The cumulative inflow into a reservoir, expressed in acre-feet (ac-ft) per month. Net inflow is the sum of tributary stream flow, inflow from upstream hydro development releases (where applicable), groundwater inflow, precipitation falling on the reservoir surface, land surface runoff, and on-reservoir point-source return flows, less the sum of on- reservoir water withdrawals, groundwater recharge, hydro development flow releases, evaporation, and other factors. 3. Normal Minimum Elevation – The level of a reservoir (measured in feet above Mean Sea Level (msl) or feet relative to the full pond contour with 100.0 ft corresponding to full pond) that defines the bottom of the reservoir’s Normal Operating Range for a given day of the year. If Net Inflows to the reservoir are within some reasonable tolerance of the average or expected amounts, hydro project equipment is operating properly, and no protocols for abnormal conditions have been implemented, reservoir level excursions below the Normal Minimum Elevation should not occur. 4. Normal Maximum Elevation – The level of a reservoir (measured in feet above Mean Sea Level (msl) or feet relative to the full pond contour with 100.0 feet corresponding to full pond) that defines the top of the reservoir’s Normal Operating Range for a given day of the year. If net inflows to the reservoir are within some reasonable tolerance of the average or expected amounts, hydro project equipment is operating properly and no protocols for abnormal Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 3 January 24, 2006 conditions have been implemented, reservoir level excursions above the Normal Maximum Elevation should not occur. 5. Normal Target Elevation - The level of a reservoir (measured in feet above Mean Sea Level (msl) or feet relative to the full pond contour with 100.0 ft corresponding to full pond) that the Licensee will endeavor in good faith to achieve, unless operating in this Low Inflow Protocol or the Maintenance & Emergency Protocol. Since inflows vary significantly and outflow demands also vary, the Licensee will not always be able to maintain actual reservoir level at the Normal Target Elevation. The Normal Target Elevation falls within the Normal Operating Range, but it is not always the average of the Normal Minimum and Normal Maximum Elevations. 6. Normal Operating Range – The band of reservoir levels within which the Licensee normally attempts to maintain a given reservoir that it operates on a given day. Each reservoir has its own specific Normal Operating Range, bounded by a Normal Maximum Elevation and a Normal Minimum Elevation. If net inflows to the reservoir are within some reasonable tolerance of the average or expected amounts, hydro project equipment is operating properly, and no protocols for abnormal conditions have been implemented, reservoir level excursions outside of the Normal Operating Range should not occur. 7. Large Water Intake – For the purposes of this Low Inflow Protocol, a Large Water Intake is any intake (e.g., public water supply, industrial, agricultural, power plant, etc.) having a maximum instantaneous capacity greater than or equal to one Million Gallons per Day (MGD) that withdraws water from the Catawba-Wateree River Basin. 8. Public Water Supply – Public Water Supply is used in this document to describe any system owned and/or operated by any governmental or private entity that utilizes waters from the Catawba-Wateree River Basin for public interest including drinking water; residential, commercial, industrial, and institutional uses; irrigation, and/or other public uses. 9. Critical Reservoir Elevation – The level of water in a reservoir (measured in feet above Mean Sea Level or feet relative to the full pond contour with 100.0 ft. corresponding to full pond) below which any large public water supply intake, large industrial intake, or regional power plant intake located on the reservoir will not operate at its Duke Power-approved capacity. The Critical Reservoir Elevations, as of the revision date of this AIP, are defined below: Reservoir Critical Reservoir Elevation (ft. relative to local datum) Type of Limit Lake James 61.0 Power Production Lake Rhodhiss 89.4 Municipal Intake Lake Hickory 94.0 Municipal Intake Lookout Shoals Lake 74.9 Municipal Intake Lake Norman 90.0 Power Production Mountain Island Lake 94.3 Power Production Lake Wylie 92.6 Industrial Intake Fishing Creek Reservoir 95.0 Municipal Intake Great Falls-Dearborn Reservoir 87.2 Power Production Cedar Creek Reservoir 80.3 Power Production Lake Wateree 92.5 Municipal Intake Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 4 January 24, 2006 10. Total Usable Storage (TUS) – The sum of the Project’s volume of water expressed in acre- feet (ac-ft) contained between each reservoir’s Critical Reservoir Elevation and the Full Pond Elevation. 11. Remaining Usable Storage (RUS) - The sum of the Project’s volume of water expressed in acre-feet (ac-ft) contained between each reservoir’s Critical Reservoir Elevation and the actual reservoir elevation at any given point in time. 12. Storage Index (SI) – The ratio, expressed in percent, of Remaining Usable Storage to Total Usable Storage at any given point in time. 13. Target Storage Index (TSI) – The ratio of Remaining Usable Storage to Total Usable Storage based on the Project reservoirs being at their Normal Target Elevations. The following table lists the Target Storage Index for the first day of each month: Month Target Storage Index (%)* Jan 63 Feb 54 Mar 63 Apr 68 May 77 Jun 77 Jul 77 Aug 77 Sep 77 Oct 77 Nov 71 Dec 64 * Target Storage Indices for other days of the month are determined by linear interpolation. 14. U.S. Drought Monitor - A synthesis of multiple indices, outlooks, and news accounts that represent a consensus of federal and academic scientists concerning the drought status of all parts of the United States. Typically, the U.S. Drought Monitor indicates intensity of drought as D0-Abnormally Dry, D1-Moderate, D2-Severe, D3-Extreme, and D4-Exceptional. The website address is http://www.drought.unl.edu/dm/monitor.html. The following federal agencies are responsible for maintaining the U.S. Drought Monitor: ƒ Joint Agricultural Weather Facility (U.S. Department of Agriculture and Department of Commerce/National Oceanic and Atmospheric Administration) ƒ Climate Prediction Center (U.S. Department of Commerce/NOAA/National Weather Service) ƒ National Climatic Data Center (DOC/NOAA) 15. U.S. Drought Monitor Three-Month Numeric Average – If the U.S. Drought Monitor has a reading of D0-D4 as of the last day of the previous month for any part of the Catawba- Wateree River Basin that drains to Lake Wateree, the Basin will be assigned a numeric value for the current month. The numeric value will equal the highest Drought Monitor designation (e.g., D0 = 0, D4 = 4) as of the last day of the previous month that existed for Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 5 January 24, 2006 any part of the Catawba-Wateree River Basin that drains to Lake Wateree. A normal condition in the Basin, defined as the absence of a Drought designation, would be assigned a numeric value of negative one (-1). A running average numeric value of the current month and the previous two months will be monitored and designated as the U.S. Drought Monitor Three-Month Numeric Average. 16. Critical Flows – The minimum flow releases from the hydro developments that may be necessary to: a. prevent long-term or irreversible damage to aquatic communities consistent with the resource management goals and objectives for the affected stream reaches; b. provide some basic level of operability for large water intakes located on regulated river reaches; and, c. provide some basic level of water quality maintenance in the affected stream reaches. For the purposes of this LIP, the Critical Flows are as follows: a. Linville River, below the Bridgewater Development: 75 cubic feet per second (cfs). b. Catawba River Bypassed Reach below the Bridgewater Development: 25 cfs c. Oxford Regulated River Reach below the Oxford Development: 100 cfs d. Lookout Shoals Regulated River Reach below the Lookout Shoals Development: 80 cfs e. Wylie Regulated River Reach below the Wylie Development: 700 cfs f. Great Falls Bypassed Reaches (Long and Short) at the Great Falls-Dearborn Development: 450 cfs and 80 cfs respectively. g. Wateree Regulated River Reach below the Wateree Development: 800 cfs 17. Recreation Flow Reductions - Since all recreation flow releases must be made by either releasing water through hydroelectric generation or through flow releases that bypass hydro generation equipment, reductions in Project Flow Requirements will impact recreation flow releases. 18. Organizational Abbreviations – Organizational abbreviations include the NC Department of Environment and Natural Resources (NCDENR), North Carolina Wildlife Resources Commission (NCWRC), South Carolina Department of Natural Resources (SCDNR), South Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 6 January 24, 2006 Carolina Department of Health and Environmental Control (SCDHEC), and the United States Geological Survey (USGS). 19. Catawba-Wateree Drought Management Advisory Group (CW-DMAG) – The CW-DMAG will be tasked with working with the Licensee when the LIP is initiated. This team will also meet as necessary to foster a basin-wide response to a Low Inflow Condition (see Procedure section of this LIP). Members of the CW-DMAG agree to comply with the conditions of this LIP. Membership on the CW-DMAG is open to the following organizations, of which each organization may have up to two members: a. NCDENR (including - Division of Water Resources and the Division of Water Quality) b. NCWRC c. SCDNR d. SCDHEC e. USGS f. Each Owner of a Large Water Intake located on one of the Catawba-Wateree Project reservoirs or the main stem of the Catawba-Wateree River g. Each Owner of a Large Water Intake located on any tributary stream within the Catawba-Wateree River Basin that ultimately drains to Lake Wateree h. Licensee (CW-DMAG Coordinator). The CW-DMAG will meet annually during the month of May, regardless of the Low Inflow Condition Status, to review prior year activities, discuss data input from Large Intake Owners, and discuss other issues relevant to the LIP. The Licensee will maintain an active roster of the CW-DMAG and update the roster as needed. 20. Revising the LIP - During the term of the New License, the CW-DMAG will be tasked with reviewing and updating the LIP. In order to ensure continuous improvement of the LIP and its implementation throughout the New License term, the LIP will be re-evaluated and modified periodically. These re-evaluations and modifications will be considered at least once every five (5) years. Modifications must be approved by a consensus of the participating CW-DMAG members. If the participating members cannot reach consensus, then the procedures identified in Section ___ will be used for resolving the dispute. Approved modifications will be incorporated through revision of this LIP and the Licensee will file the revised LIP with FERC. In addition, if any modifications of the LIP require amendment of the New License, the Licensee will file a license amendment request for FERC approval. During this process the CW-DMAG may appoint an ad hoc committee to address issues and revisions relevant to the LIP. Issues such as sediment fill impact on reservoir storage volume calculations, and substitution of a regional drought monitor for the U.S. Drought Monitor, if developed in the future, are examples of items that may be re- evaluated. The Licensee will prepare meeting summaries of all CW-DMAG meetings and will make these meeting summaries available to the public by posting on its website. 21. Water Withdrawal Data Collection and Reporting – All owners of Large Water Intakes located on Project reservoirs will, on an annual basis, report daily and average monthly metered water withdrawals (in MGD) to the Licensee. The Licensee will maintain a database of this information including the Licensee’s own non-hydro water use records (i.e. water uses due to thermal power generation). These annual withdrawal summaries will be due by January 31 of each year for the preceding calendar year. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 7 January 24, 2006 22. Reclaimed Water – Wastewater that has been treated to reclaimed water standards and is re-used for a designated purpose (e.g. industrial process, irrigation). Reclaimed Water will not be subject to the restrictions outlined in this Procedure. 23. Drought Response Plan Updates – All Large Water Intake Owners will review and update their Drought Response Plans (or develop a plan if they do not have one) to ensure compliance and coordination with this LIP, including the authority to enforce the provisions outlined herein. 24. Relationship Between the LIP and the Maintenance & Emergency Protocol (MEP) – The MEP outlines the response the Licensee will take under certain emergency and equipment failure and maintenance situations to continue practical and safe operation of the Project, to mitigate any related impacts to license conditions, and to communicate with resource agencies and the affected parties. Under the MEP, temporary modifications of minimum flow releases and the reservoir level operating ranges are allowed. Lowering levels of Project reservoirs caused by situations addressed under the MEP will not invoke implementation of this Low Inflow Protocol (LIP). Also, if the LIP has already been implemented at the time that a situation covered by the MEP is initiated, the Licensee will typically suspend implementation of the LIP until the MEP situation has been eliminated. The Licensee may, however, choose to continue with the LIP if desirable. 25. Consensus – Consensus is reached when all CW-DMAG members can ‘live with’ the outcome or proposal being made. The concept of consensus is more fully described in the Catawba – Wateree Hydroelectric Project Relicensing – Stakeholder Team Charter (dated October, 2005). 26. Monitored USGS Streamflow Gages - USGS streamflow gage #’s 02145000 (South Fork Catawba River at Lowell, NC), 02137727 (Catawba River near Pleasant Gardens, NC), 02140991 (Johns River at Arneys Store, NC), and 02147500 (Rocky Creek at Great Falls, SC) 27. Human Health and Safety and the Integrity of the Public Water Supply and Electric Systems are of Utmost Importance – Nothing in this protocol will limit the Licensee’s ability to take any and all lawful actions necessary at its hydro projects to protect human health and safety, protect its equipment from major damage, protect the equipment of the Large Intake Owners from major damage, and ensure the stability of the regional electric grid. It is recognized that the Licensee may take the steps that are necessary to protect these things without prior consultation or notification. ASSUMPTIONS 1. Instream Flows for Recreation – The New License for the Catawba-Wateree Project includes the prescribed recreational flow releases as listed in Section 3.0 of this AIP. 2. Instream Flows for Aquatic Habitat/Water Quality/Navigation – The New License for the Catawba-Wateree Project includes the instream flow requirements for Aquatic Habitat/Water Quality/Navigation as listed in Section 4.0 of this AIP, including flow requirements in bypassed reaches. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 8 January 24, 2006 3. Water Management to Support Water Users - The New License for the Catawba-Wateree Project includes water management to support water users as listed in Section 5.0 of this AIP. 4. Project Flow Requirements – These flow requirements include Instream Flows for Aquatic Habitat/Water Quality/Navigation and the portion of Instream Flows for Recreation that is greater than the Instream Flows for Aquatic Habitat/Water Quality/Navigation as identified in Sections 3.0 and 4.0 of this AIP for normal conditions (i.e., conditions outside of this LIP or the Maintenance and Emergency Protocol). 5. Public Information System – The Licensee will maintain public information readily available on its website and toll-free telephone system as identified in Section 8.0 of this AIP. 6. Normal Operating Ranges for Reservoirs – The New License for the Catawba-Wateree Project includes the Normal Operating Ranges for the reservoirs (i.e., Normal Minimum, Normal Maximum, and Normal Target Elevations) as listed in Section 2.0 of this AIP. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 9 January 24, 2006 PROCEDURE During periods of normal inflow, reservoir levels will be maintained within prescribed Normal Operating Ranges. During times that inflow is not adequate to meet all of the normal demands for water and maintain reservoir levels as normally targeted, the Licensee will progressively reduce hydro generation while meeting Project Flow Requirements. During a Low Inflow Watch or a Low Inflow Condition (LIC) (as defined below), the Licensee and other water users will follow the protocol set forth below for the Catawba-Wateree Project regarding communications and adjustments to hydro releases, bypassed flow releases, minimum reservoir elevations, and other water demands. The adjustments set forth below will be made on a monthly basis and are designed to equitably allocate the impacts of reduced water availability in accordance with the purpose statement of this LIP. Triggers points that demonstrate worsening hydrologic conditions will define various stages of the Low Inflow Condition. A summary of trigger points for various stages is provided in the table below. The specific triggers required to enter successive stages are defined in the procedure for each stage. Summary of LIP Trigger Points Stage Storage Index 1 Drought Monitor 2 (3-month average) Monitored USGS 3 Streamflow Gages 04 90% < SI < TSI 0 ≤ DM AVG ≤ 85% 1 75% < SI ≤ 90%TSI and 1 ≤ DM or AVG ≤ 78% 2 57% < SI ≤ 75%TSI and 2 ≤ DM or AVG ≤ 65% 3 42% < SI ≤ 57%TSI and 3 ≤ DM or AVG ≤ 55% 4SI ≤ 42%TSI and DM = 4 or AVG ≤ 40%1 The ratio of Remaining Useable Storage to Total Usable Storage at a given point in time. 2 The three-month numeric average of the published U.S. Drought Monitor. 3 The sum of the rolling sixth-month average for the monitored streamflow gages as a percentage of the period of record rolling average for the same six-month period for the monitored streamflow gages. 4 Stage 0 is triggered when any two of the three trigger points are reached. Stage 0 - Low Inflow Watch: The Licensee will monitor the Storage Index, the U.S. Drought Monitor, and the Monitored USGS Streamflow Gages on at least a monthly basis and will declare a Stage 0 - Low Inflow Watch if any two of the following conditions occur: a. On the first day of the month, Storage Index is below the Target Storage Index, but greater than 90% of the Target Storage Index, while providing the Project Flow Requirements for the previous month. b. The U.S. Drought Monitor Three-Month Numeric Average has a value greater than or equal to 0. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 10 January 24, 2006 c. The sum of the actual rolling six-month average streamflows at the Monitored USGS Streamflow Gages is equal to or less than 85% of the sum of the period of record rolling average streamflows for the same six-month period. When a Low Inflow Watch has been declared: a. The Licensee will activate the CW-DMAG, including the initiation of monthly meetings or conference calls to occur on the second Tuesday of each month. These monthly discussions will focus on: ƒ Proper communication channels between the CW-DMAG members. ƒ Information reporting consistency for CW-DMAG members, including a storage index history and forecast (at least a 90-day look back and look ahead) from the Licensee, a water use history and forecast (at least a 90-day look back and look ahead) from each water user on the CW-DMAG, streamflow gage and groundwater monitoring status from the state agencies and USGS, and state- wide drought response status from the state agencies. ƒ Refresher training on this LIP. ƒ Overview discussions from each CW-DMAG member concerning their role and plans for responding if a Low Inflow Condition is subsequently declared. b. In addition, the Licensee will reduce the prescribed recreation flow releases at the Wylie Development from 6,000 cfs to 3,000 cfs. Stage 1 Actions: 1. The Licensee will declare a Stage 1 LIC and notify the CW-DMAG if: a. On the first day of the month, Storage Index is at or below 90% of the Target Storage Index, but greater than 75% of the Target Storage Index, while providing the Project Flow Requirements for the previous month. and either of the following conditions exists: b. The U.S. Drought Monitor Three-Month Numeric Average has a value greater than or equal to 1. c. The sum of the actual rolling six-month average streamflows at the Monitored USGS Streamflow Gages is equal to or less than 78% of the sum of the period of record rolling average streamflows for the same six-month period. 2. The Licensee will complete the following activities within 5 days after the Stage 1 LIC declaration: a. Reduce the Project Flow Requirements by 60% of the difference between the Project Flow Requirements and the Critical Flow. These reduced Project Flow Requirements are referred to as Stage 1 Minimum Project Flows. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 11 January 24, 2006 b. Reduce the Normal Minimum Elevations by one foot at each reservoir, except two feet at Lake James and Lake Norman, but not to levels at any reservoir below the Critical Reservoir Elevations. These elevations are referred to as the Stage 1 Minimum Elevations. c. Update its website and IVR messages to account for the impacts of the LIP on reservoir levels, usability of Duke Power public access areas, and recreation flow schedules. d. Provide bi-weekly (once every two weeks) information updates to owners of Large Water Intakes about lake levels, meteorological forecasts, and inflow of water into the system. 3. Owners of Public Water Supply intakes and other intakes with a capacity greater than 100,000 gallons per day used for irrigation will complete the following activities within 14 days after the Stage 1 LIC declaration: a. Notify their water customers of the low inflow condition through public outreach and communication efforts. b. Request that their water customers implement voluntary water use restrictions, in accordance with their drought response plans, which may include: ƒ Reduction of lawn and landscape irrigation to no more than two days per week (i.e. residential, multi-family, parks, streetscapes, schools, etc). ƒ Reduction of residential vehicle washing. At this level, the goal is to reduce water usage by approximately 3-5% from the amount that would otherwise be expected. The baseline for this comparison will be generated by each entity and will be based on existing conditions (i.e. drought conditions). For the purposes of determining ‘the amount that would otherwise be expected’, each entity may give consideration to one or more of the following: ƒ Historical maximum daily, weekly, and monthly flows during drought conditions. ƒ Increased customer base (e.g. population growth, service area expansion) since the historical flow comparison. ƒ Changes in major water users (e.g. industrial shifts) since the historical flow comparison. ƒ Climatic conditions for the comparison period. ƒ Changes in water use since the historical flow comparison. ƒ Other system specific considerations. c. Provide a status update to the CW-DMAG on actual water withdrawal trends. Discuss plans for moving to mandatory restrictions, if required. 4. Owners of Large Water Intakes, other than those referenced in item 3 above, will complete the following activities within 14 days after the Stage 1 LIC declaration: a. Notify their customers of the low inflow condition through public outreach and communication efforts. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 12 January 24, 2006 b. Request that their customers conserve water through reduction of water use, electric power consumption, and other means. c. Provide a status update to the CW-DMAG on actual water withdrawal trends. Stage 2 Actions: 1. The Licensee will declare a Stage 2 Low Inflow Condition (LIC) and notify the CW-DMAG if: a. On the first day of the month, Storage Index is at or below 75% of the Target Storage Index, but greater than 57% of the Target Storage Index, while providing the Stage 1 Minimum Project Flows during the previous month. and either of the following conditions exists: b. The U.S. Drought Monitor Three-Month Numeric Average has a value greater than or equal to 2. c. The sum of the actual rolling six-month average streamflows at the Monitored USGS Streamflow Gages is equal to or less than 65% of the sum of the period of record rolling average streamflows for the same six-month period. 2. The Licensee will complete the following activities within 5 days after the Stage 2 LIC declaration: a. Eliminate prescribed recreation flow releases at this stage and all subsequent stages. Reduce the remaining Project Flow Requirements by 95% of the difference between the Project Flow Requirements and Critical Flow. These reduced flows are referred to as Stage 2 Minimum Project Flows. b. Reduce the Stage 1 Minimum Elevations by one additional foot (two feet total below Normal Minimum Elevation) at each reservoir, except by one additional foot at Lake James (three feet total below Normal Minimum Elevation) and two additional feet at Lake Norman (four feet total below Normal Minimum Elevation), but not to levels at any reservoir below the Critical Reservoir Elevations. These elevations are referred to as the Stage 2 Minimum Elevations. c. Update its website and IVR messages to account for the impacts of the LIP on reservoir levels, usability of Duke Power public access areas, and recreation flow schedules. d. Provide bi-weekly information updates to owners of Large Water Intakes about lake levels, meteorological forecasts, and inflow of water into the system. 3. Owners of Public Water Supply intakes and other intakes with a capacity greater than 100,000 gallons per day used for irrigation will complete the following activities within 14 days after the Stage 2 LIC declaration: a. Notify their water customers of the continued low inflow condition and movement to mandatory water use restrictions through public outreach and communication efforts. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 13 January 24, 2006 b. Require that their water customers implement mandatory water use restrictions, in accordance with their drought response plans, which may include: ƒ Limiting lawn and landscape irrigation to no more than two days per week (i.e. residential, multi-family, parks, streetscapes, schools, etc). ƒ Eliminating residential vehicle washing. ƒ Limiting public building, sidewalk, and street washing activities except as required for safety and/or to maintain regulatory compliance. At this level, the goal is to reduce water usage by approximately 5-10% from the amount that would otherwise be expected (as discussed in Stage 1 above). c. Enforce mandatory water use restrictions through the assessment of penalties. d. Provide a status update to the CW-DMAG on actual water withdrawal trends. 4. Owners of Large Water Intakes, other than those referenced in item 3 above, will complete the following activities within 14 days after the Stage 2 LIC declaration: a. Continue informing their customers of the low inflow condition through public outreach and communication efforts. b. Request that their customers conserve water through reduction of water use, electric power consumption, and other means. c. Provide a status update to the CW-DMAG on actual water withdrawal trends. Stage 3 Actions: 1. The Licensee will declare a Stage 3 Low Inflow Condition (LIC) and notify the CW-DMAG if: a. On the first day of the month, Storage Index is at or below 57% of the Target Storage Index, but greater than 42% of the Target Storage Index, while providing the Stage 2 Minimum Project Flows during the previous month. and either of the following conditions exists: b. The U.S. Drought Monitor Three-Month Numeric Average has a value greater than or equal to 3. c. The sum of the actual rolling six-month average streamflows at the Monitored USGS Streamflow Gages is equal to or less than 55% of the sum of the period of record rolling average streamflows for the same six-month period. 2. The Licensee will complete the following activities within 5 days after the Stage 3 LIC declaration: a. Reduce the Stage 2 Minimum Project Flows to Critical Flows. These reduced flows are referred to as Stage 3 Minimum Project Flows. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 14 January 24, 2006 c. Reduce the Stage 2 Minimum Elevations by one additional foot (three feet total below Normal Minimum Elevation) at each reservoir, except by seven additional feet at Lake James (ten feet total below Normal Minimum Elevation) and one additional foot at Lake Norman (five feet total below Normal Minimum Elevation), but not to levels at any reservoir below the Critical Reservoir Elevations. These elevations are referred to as the Stage 3 Minimum Elevations. d. Update its website and IVR messages to account for the impacts of the LIP on reservoir levels, usability of Duke Power public access areas, and recreation flow schedules. e. Provide bi-weekly information updates to owners of Large Water Intakes about lake levels, meteorological forecasts, and inflow of water into the system. 3. Owners of public water supply intakes and other intakes with a capacity greater than 100,000 gallons per day used for irrigation will complete the following activities within 14 days after the Stage 3 LIC declaration: a. Notify their water customers of the continued low inflow condition and movement to more stringent mandatory water use restrictions through public outreach and communication efforts. b. Require that their water customers implement increased mandatory water use restrictions, in accordance with their drought response plans, which may include: ƒ Limiting lawn and landscape irrigation to no more than one day per week (i.e. residential, multi-family, parks, streetscapes, schools, etc). ƒ Eliminating residential vehicle washing. ƒ Limiting public building, sidewalk, and street washing activities except as required for safety and/or to maintain regulatory compliance. ƒ Limiting construction uses of water such as dust control. ƒ Limiting flushing and hydrant testing programs, except to maintain water quality or other special circumstances. ƒ Eliminating the filling of new swimming pools. At this level, the goal is to reduce water usage by approximately 10-20% from the amount that would otherwise be expected (as discussed in Stage 1 above). c. Enforce mandatory water use restrictions through the assessment of penalties. d. Encourage industrial/manufacturing process changes that reduce water consumption. e. Provide a status update to the CW-DMAG on actual water withdrawal trends. 4. Owners of Large Water Intakes, other than those referenced in item 3 above, will complete the following activities within 14 days after the Stage 3 LIC declaration: a. Continue informing their customers of the low inflow condition through public outreach and communication efforts. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 15 January 24, 2006 b. Request that their customers conserve water through reduction of water use, electric power consumption, and other means. c. Provide a status update to the CW-DMAG on actual water withdrawal trends. Stage 4 Actions: 1. The Licensee will declare a Stage 4 Low Inflow Condition (LIC) and notify the CW-DMAG if: a. On the first day of the month, Storage Index is at or below 42% of the Target Storage Index, while providing the Stage 3 Minimum Project Flows during the previous month. and either of the following conditions exists: b. The U.S. Drought Monitor Three-Month Numeric Average has a value of 4. c. The sum of the actual rolling six-month average streamflows at the Monitored USGS Streamflow Gages is equal to or less than 40% of the sum of the period of record rolling six-month average streamflows for the same six-month period. 2. The Licensee will: a. Continue to provide Critical Flows as long as possible. b. Reduce the Stage 3 Minimum Elevations to the Critical Reservoir Elevations. c. Establish a meeting date and notify the CW-DMAG within 1 day following the Stage 4 LIC declaration. d. Continue to update its website and IVR messages to account for the impacts of the LIP on reservoir levels, usability of Duke Power public access areas, and recreation flow schedules. e. Provide bi-weekly information updates to owners of Large Water Intakes about lake levels, meteorological forecasts, and inflow of water into the system. Note: In a Stage 4 LIC, the Remaining Usable Storage in the reservoir system is small and can be fully depleted in a matter of weeks or months. Groundwater recharge may also contribute to declining reservoir levels. For these reasons in the Stage 4 LIC, the Licensee may not be able to ensure that releases from its hydro developments will meet or exceed Critical Flows or that reservoir elevations will be greater than or equal to the Critical Reservoir Elevations. 3. Owners of public water supply intakes and other intakes with a capacity greater than 100,000 gallons per day used for irrigation will complete the following activities within 14 days after the Stage 4 LIC declaration: Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 16 January 24, 2006 a. Notify their water customers of the continued low inflow condition and movement to emergency water use restrictions through public outreach and communication efforts. b. Restrict all outdoor water use. c. Implement emergency water use restrictions in accordance with their drought response plans, including enforcement of these restrictions and assessment of penalties. d. Prioritize and meet with their commercial and industrial large water customers to discuss strategies for water reduction measures including development of an activity schedule and contingency plans. e. Prepare to implement emergency plans to respond to water outages. At this level, the goal is to reduce water usage by approximately 20-30% from the amount that would otherwise be expected (as discussed in Stage 1 above). 4. Owners of Large Water Intakes on the CW-DMAG, other than those referenced in item 3 above, will complete the following activities within 14 days after the Stage 4 LIC declaration: a. Continue informing their customers of the low inflow condition through public outreach and communication efforts. b. Request that their customers conserve water through reduction of water use, electric power consumption, and other means. 5. The CW-DMAG will: a. Meet within 5 days after the declaration of the Stage 4 LIC and determine if there are any additional measures that can be implemented to: (1) reduce water withdrawals; (2) reduce water releases from the Project; or (3) utilize additional reservoir storage without creating more severe regional problems. b. Work together to develop plans and implement any additional measures identified above. Recovery from the Low Inflow Protocol 1. Recovery from the LIP will simply reverse the same staged approach as noted above, except that: a. All the trigger points identified above for declaring the lower numbered stage must be met or exceeded before returning reservoir levels and flows to that LIC stage, Low Inflow Watch, or Normal Conditions. Catawba-Wateree Agreement-in-Principle (AIP) CW AIP LIP Attachment G 1-24-06.doc 17 January 24, 2006 b. The following groundwater level trigger points must also be attained before returning reservoir levels and flows to that LIC stage, Low Inflow Watch, or Normal Conditions: USGS has reviewed available well records and has determined that there are existing wells with an adequate period that can be used for this process and has also determined that additional wells are needed in order to include groundwater as part of the recovery. Groundwater Trigger Points (depth below land surface (feet)) for Returning to: Groundwater Monitor [Reg.=regolith; BR=bedrock] Stage 3 (a) Stage 2 (b) Stage 1 (c) LIW (d) Normal (d) #1 #2 #3 #4 #5 #6 USGS Langtree Peninsula RS Reg. well MW-2 & BR well MW-2D 24.91 23.61 22.21 18.21 18.21 #7 USGS Linville RS NC- 220 BR well 2.74 2.19 2.11 2.04 2.04 #8 NC DWR Glen Alpine BR well L 76G2 10.01 9.03 8.32 7.69 7.69 #9 #10 Note: USGS groundwater levels calculated from daily mean data. NCDWR water levels calculated from hourly data. All trigger levels calculated from water levels collected through the 2005 water year. Trigger groundwater levels may be updated on a yearly or water-year basis. Footnotes: (a) Stage 3: Period of record low water level (b) Stage 2: 10th percentile (c) Stage 1: 25th percentile (d) LIW and Normal: 50th percentile 2. The NCDENR, SCDNR, SCDHEC, USGS and the Licensee will determine when attainment of the groundwater trigger points for recovery is reached. 3. The Licensee will directly notify the CW-DMAG members within 5 days following attainment of all the trigger points necessary to recover to a lower stage of the LIC, Low Inflow Watch, or Normal Conditions. 4. The Licensee will update its website and IVR messages to account for the impacts of the LIP on reservoir levels, usability of Duke Power public access areas, and recreation flow schedules.