HARTWELL DAM AND LAKE
GEORGIA AND SOUTH CAROLINA
VII HARTWELL WATER CONTROL PLAN
H7-01. General Objectives.
The authorized purposes of the Hartwell project are to provide water supply, hydroelectric power, flood control, fish and wildlife, water quality and recreation benefits. The operation of the Hartwell project will be to maximize the benefits of these authorized purposes. The Savannah District is responsible for ensuring attainment of the maximum public benefits from each of its water resource projects consistent with the objectives and specific provisions of the authorizing legislation and applicable Corps of Engineers' directives for the project.
H7-02 . Overall Plan for Water Control .
Water control management decisions at the Hartwell Project consider hydrologic and climatologic factors, conditions at the downstream projects, potential threats of flood or drought, present and projected lake levels, and the constraints of recreation, wildlife management, water quality, water supply, and hydroelectric power production. Evaluation of these factors requires well qualified technically trained personnel with special experience in the field of modern hydrology, hydraulic engineering, and water control management. The Savannah District maintains this expertise in the Hydraulics Section of the Hydrology and Hydraulics Branch (the Water Control Center) with the assistance of fish and wildlife and recreation experts from the Operations Division. Close coordination with the plant operators, whose experience and on-site location makes them a vital part of the water control team, is essential. The Savannah District reports water control conditions and activities to the South Atlantic Division (SAD) office in Atlanta.
The Hartwell Project includes 35 feet of conservation storage (elevation 625 to 660 feet NGVD, 1,415,500 ac-ft) and 5 feet of flood control storage (elevation 660 to 665 feet NGVD, 293,100 ac-ft). The project has limited flood control storage during the spring and early summer but increases as the project follows the drawdown in accordance with the rule curve. The area capacity curve can be found on Plate H7.3.
a. System Management Decisions concerning water control for the Hartwell Project are part of a coordinated multi-reservoir system regulation for the Savannah River Basin, as well as part of the operation of the larger power network for the southeastern United States (coordinated through SAD).
Additional regulation is provided by several independent hydroelectric projects in the upland area of the basin. Duke Power Company entered into an operating agreement with the Corps of Engineers upon completion of the Keowee-Jocassee Project. The percentage of conservation storage remaining in lakes Keowee and Jocassee was to be kept in balance with the average percentage of storage remaining at the Hartwell and J. Strom Thurmond projects. This agreement was to minimize the impact of the headwater projects on the operation of the existing Corps projects. An outline of the agreement is shown as Exhibit C.
b. Compatibility Among Purposes . The primary uses of the Hartwell Project that would appear to conflict are flood control and hydroelectric power generation. Regulation for flood control minimizes the quantity of water held by the dam in anticipation of keeping the maximum amount of storage available for flood inflows. Regulation for power production maximizes the water quantity and water surface elevation behind the dam to meet power demands which vary daily, weekly, and seasonally. The objective, then, is to provide a maximum power pool (660 ft. NGVD) for hydropower generation while having sufficient storage to handle upstream flood flows. Additional flexibility is provided by the seasonality of flood flows, seasonal, weekly, and daily variations in peaking power demand, integrated basin regulation, and coordinated southeastern power system operations.
Other uses may also compete for water from the Hartwell Project. Potential for conflict exists among the following:
(1) Fish and wildlife or water quality and releases for flood control. During flood control operations, passing inflow through the project may have negative impacts on water quality or fisheries, both within the lake and downstream.
(2) Fish and wildlife or water quality and turbine releases for power (see section H7-11 below).
(3) Recreation and water supply and hydropower. Particularly during drought periods, potential exists for such a conflict. Continued power generation to meet contractual obligations for electrical power when pool elevations may negatively impact recreational users of the lake.
(4) Recreation and flood control. Due to the risk of flood damages and injuries, any necessary flood control regulation is given highest priority.
c. Normal Regulation Activities . Long term planning and supervision of the operation of rainfall and river stage reporting works is a responsibility of the Water Control Center. Weekly reservoir control activities are as follows:
(1) Weekly Water Volume Analysis . The Water Control Manager compiles necessary basic data on precipitation, river stages, reservoir elevations, and general streamflow conditions, and prepares inflow, discharge, storage and pool elevation predictions by noon each Wednesday for the following week and makes water generation availability analysis and forecasts for the three-reservoir system. Projections consider guide curves, power contract commitments, antecedent moisture conditions, expected rainfall, and rainfall-runoff relationships for the upper Savannah River Basin. Additional considerations that might affect discharges are powerplant maintenance activities, proposed operational changes that would affect power generation, and water level management activities related to fisheries or recreation. Input concerning these matters are normally received on Wednesdays from the Planning Division and the Technical Support Branch of Operations Division.
(2) Weekly Report To The South Atlantic Division (SAD) . The Water Control Center transmits the recommended schedule of power generation to the Water Management Branch at SAD by Wednesday afternoon. Following SAD consultation with the Southeastern Power Administration (SEPA), the marketing agency for federally generated power in the southeast, SAD coordinates any changes to the schedule with the Water Control Center.
(3) Weekly Meeting . Each Thursday morning the Water Control Manager conducts a meeting with Operations and Planning Division personnel to review storage and pool elevation projections and power generation availability analyses. The Water Control Manager transmits water control data to SAD.
(4) Final Generation Schedule . Following confirmation by SEPA, SAD advises the Water Control Center each Friday of the amount of energy to be taken from each of the three projects. SEPA's customers (the power companies) furnish hourly schedules directly to the Project Operator with copies furnished to the Water Control Center.
H7-03. Standing Instructions to Project Operator.
A summary of reservoir regulation procedures for the project operator during both normal and emergency situations is found in Exhibit H7-A. Standing instructions are essential to ensure efficient and safe operation of the project at all times: during normal conditions, communication outages, unforeseen and emergency events. These instructions clearly outline the physical operating constraints (spillway or outlet work restrictions) which ensure operation in a safe manner and within design limitations.
The Hydraulics Section, Hydrology and Hydraulics Branch, Engineering Division, is responsible for water control management within the Savannah District, including the regulation of the Hartwell Project to achieve its project purposes. Operations Division is responsible for the operation and maintenance of these projects. Assigning responsibility for water control management to the Hydraulics Section does not diminish the necessity for or the desirability of appropriate and adequate interstaff coordination. Hydraulics Section is responsible for insuring that such coordination has been effected and subsequent actions are taken. The Project Operator is responsible to the Water Control Manager for all water control actions.
Transmission of instructions from the Water Control Manager through several individuals or organizational units can be a source of delay and misunderstandings. Clear lines of communication and authority must be maintained. Occasionally, water control management decisions necessitate that the Water Control Manager (in Engineering Division) contact the Project Operator directly so that satisfactory instructions can be given or hydrologic data can be obtained. Particularly during time of emergencies, there must be no delay in transmission of instructions or hydrologic data between the Project Operator and the Water Control Manager. In these instances, the Project Operator will act on instructions received directly from the Water Control Manager on all matters regarding the regulation of water. Advisory notification is furnished to Operations Division as soon as possible.
H7-04 . Flood Control .
a. General Regulation . Normal conditions exist when there is no flood, drought or other emergency and none are anticipated. The Hartwell Project includes 5 feet of flood control storage (elevation 660 to 665 feet NGVD, 293,100 acre-feet). A seasonally varying guide curve, shown on Plate H7.8, from elevation 656 to 660 feet, NGVD, provides additional flood control during the winter and early spring.
b. Flood Regulation . The Water Control Manager performs flood routings and makes lake elevation and river stage forecasts, and coordinates and schedules lake releases during flood periods. Flood forecasting is accomplished using the Hydrologic Engineering Center (HEC) computer software HEC-1F, a rainfall model that uses real-time precipitation data to estimate inflows at the projects. HEC-5, an HEC model that simulates and analyzes the operation of reservoir systems, is a highly complex multi-purpose, multiple reservoir system simulation tool. The model is capable of evaluating a reservoir system to determine the best operation for water quantity and quality, evaluating operational concerns such as flood control, hydropower and water supply. Mod-5 is an interactive version of HEC-5, and will enable the Water Control Manager to model various release scenarios to best manage the projects.
During floods, the Water Control Manager forwards reports as necessary to SAD containing data on predicted peak stages and percentage of flood control storage utilized. The Water Control Manager informs responsible District personnel on critical weather and streamflow conditions affecting the public and District activities and coordinates with the Public Affairs Office to issue flood reports on flood emergencies. The Operations Division Readiness Branch (OP-E) coordinates implementation of evacuation plans with local government agencies in advance of any flood release, and dispatches flood survey teams to affected areas and notifies local officials that District facilities and personnel are available upon request to assist in emergency conditions.
When the possibility of flooding conditions at or downstream of the reservoirs exists, the Readiness Branch (OP-E) is contacted. The Water Control Manager furnishes a forecast of pool elevations and releases to be made to meet flood control requirements to the Water Management Branch, SAD. At least one of the following SAD personnel will be contacted at any time during a flood emergency:
|Mr. Chris Smith||Office||N/A|
|Mr. Trent Ferguson||Office||N/A|
a. General Information . These "Standing Instructions to
the Project Operator for Water Control" are written in compliance
with Paragraph 9-2 of Engineering Manual 1110-2-3600 (Engineering and Design,
MANAGEMENT OF WATER CONTROL SYSTEMS, 30 November 1987) and with Engineer
Regulation 1110-2-240 (Engineering and Design, WATER CONTROL MANAGEMENT,
8 October 1982).
(1) Project Purposes . The Hartwell Project is operated for Hydropower, Recreation, Fish and Wildlife, Flood Control, Water Supply and Water Quality .
(2) Chain of Command . The Project Operator is responsible to the Water Control Manager for all water control actions.
(3) Structure . The Hartwell Dam is located at Savannah River Mile 288.9, Hartwell County, Georgia. The dam is a concrete gravity and earth embankment structure with a concrete gravity ogee spillway. The Hartwell (ft NGVD) is located on the Georgia (west) side, immediately downstream of the dam.
(4) Operations and Maintenance (O&M). All O&M activities are the responsibility of the U.S. Army Corps of Engineers.
b. Role of the Project Operator .
(1) Normal Conditions (dependent on day-to-day situation ). During normal conditions, all releases will be made through the turbine units. The water control manager will coordinate the weekly water control actions with SEPA. The Project Operator will then receive instructions from SEPA. This communication will be increased to a daily basis if the need develops.
(2) Emergency Conditions (flood or drought) . The Project Operator will be instructed by water control managers on a daily or hourly basis for water control actions during flood events and other emergency conditions. In the event that communications with water control managers are cut off during a flood event, the operator should regulate plant discharge in accordance with Plate H7.4, Flood Control Release Schedule, Plate H7.5, Spillway Gate Regulation Schedule, and Plate H7.6, Tainter Gate Rating Curves.
a. Normal Conditions . Project data is recorded hourly by the project operator. The data is retrieved hourly by the Water Control Manager and loaded into the Water Control Data System. The data is subsequently made available on the Water Management web site at http://water.sas.usace.army.mil:
(1) Pool Elevations in feet NGVD are collected hourly.
(2) Basin Average Precipitation in hundredths of an inch is estimated hourly from NWS doppler radar.
(3) Tailwater Elevations in feet NGVD are collected hourly.
(4) Discharge in cubic feet per second is collected hourly.
(5) Inflow to the lake in cubic feet per second is collected hourly.
(6) Scheduled and Actual Generation in megawatt-hours is collected hourly.
b. Emergency Conditions . Report hourly the elevation, turbine discharge, spillway discharge, and general project status to the Water Control Manager.
c. Regional Hydro-meteorological Conditions . The Project Operator will be informed by the Water Control Manager of regional hydrometeorological conditions that may impact the structure.
a. Normal Conditions . The Project Operator reports directly
to the Water Control Manager.
b. Emergency Conditions . The Project Operator will follow the Savannah River Emergency Action Plan (District Pamphlet 1130-2-16, Appendix B) for emergency notification procedures.
c. Inquiries . All significant inquiries received by the Project Operator from citizens, constituents or interest groups regarding water control procedures or actions must be referred directly to the Water Control Manager.
d. Water Control Problems . The Project Operator must immediately notify the Water Control Manager, by the most rapid means available, in the event that an operational malfunction, erosion or other incident occurs that could impact project integrity in general, or water control capability in particular. Such incidents are discussed in Appendix A of DP 1130-2-16, the Emergency Action Plan.
HARTWELL DAM AND LAKE
|In the Piedmont Physiographic Province at Latitude 34 o 21' north, Longitude 82o 48' west|
|On the Savannah River:|
|288.9 miles above the mouth|
|274.5 miles above Savannah, Georgia|
|89.3 miles above Augusta, Georgia|
|67.3 miles above Thurmond Dam|
|29.8 miles above Russell Dam|
|In Hart County, Georgia 7 miles east of Hartwell, Georgia 2300 feet upstream of U.S. Highway 29|
|DRAINAGE AREA||percentage||square miles|
|Above the mouth of the Savannah River||100||10,579|
|Above Augusta, Georgia (Butler Cr. gage)||71||7,508|
|Above J. Strom Thurmond Dam||58||6,144|
|Above Richard B. Russell Dam||27||2,890|
|Above Hartwell Dam||20||2,088|
|Basin between Russell Dam and Hartwell Dam||8||802|
|STORAGE VOLUMES||Elevation (ft NGVD)||Acre-feet|
|Spillway design flood||674.0||3,430,000|
|Standard project flood||667.9||3,020,000|
|Flood control pool||665.0||2,842,700|
|Maximum conservation pool||660.0||2,550,000|
|Minimum conservation pool||625.0||1,134,100|
|Conservation storage, usable||625 to 660||1,416,000|
|Flood storage||660 to 665||293,000|
|Surcharge storage||665 to 674||596,000|
|POWERPLANT ELEVATIONS||Elevation (ft NGVD)|
|Bottom of draft tube||442|
|RESERVOIR AREAS||Elevation(ft NGVD)||Acres|
|Spillway design flood (Max Surcharge Pool)||674.0||71,300|
|Standard project flood||667.9||64,800|
|Flood control pool||665.0||61,400|
|Maximum conservation pool||660.0||55,950|
|Minimum conservation pool||625.0||27,650|
|Limits of clearing||630 to 661||26,600|
|below 630||Partial clearing|
|DAM, SPILLWAY, INTAKE AND POOL ELEVATIONS||Feet NGVD|
|Top of dam||679.0|
|Maximum Observed Pool||665.40||4/8/1964|
|Minimum Observed Pool||637.49||12/10/2008|
|Spillway design flood||674.0|
|Induced surcharge pool||674.0|
|Standard project flood||667.9|
|Top of tainter gates, closed||665.0|
|Flood control pool||665.0|
|Maximum conservation pool||660.0|
|Average conservation pool||652.0|
|Minimum conservation pool||625.0|
|Intake invert for Hydropower||500.0|
|Spillway bucket lip||517.0|
|Elevation, bottom of sluice||500.0|
|Draft tube exit||442.0|
|DAM, SPILLWAY AND INTAKE DIMENSIONS|
|Concrete gravity and earth embankment with concrete gravity ogee spillway|
|Length of concrete sections||1900 feet|
|Length of earth embankment||15,952 feet|
|Maximum height of concrete section||204 feet|
|Maximum height of earth embankment||106 feet|
|Length of intake section||340 feet|
|Number of sluices||2|
|Width of sluices||5.67 feet|
|Height of sluices||10 feet|
|Gross length of spillway||568 feet|
|Length of clear opening||568 feet|
|Tainter gates (12)||each 40 feet wide by 35.5 feet high|
|Flip bucket||20 degrees|
|Radius of bucket||40 feet|
|TAILWATER ELEVATIONS||Feet NGVD|
|Spillway design flood||519.3||565,000 cfs|
|Standard project flood||512.0||420,000 cfs|
|(ft NGVD) Design flood||510.0||380,000 cfs|
|Maximum pool of record||491.6|
|Four units operating at average head||481.6|
|Maximum static condition||482.6|
|DESIGN FLOWS||Cubic feet per second|
|Spillway Design Flood||Peak Reservoir Inflow||875,000 cfs|
|Maximum Estimated Outflow||565,000 cfs|
|Standard Project Flood (SPF)||Peak Reservoir Inflow||435,000 cfs|
|Maximum Estimated Outflow||325,000 cfs|
|Initial units||four conventional|
|Supplimental Units||one conventional|
|Maximum net operating head||192 feet|
|Average operating head||171 feet|
|Minimum operation head||142 feet|
|Turbine capacity at average head||91,500 hp per unit|
|Maximum discharge at minimum head||6500 cfs per unit|
|Length of draft tube||66 feet|
|Initial installation - four conventional units each at||66 MW initial||85 MW current|
|Supplemental installation - one conventional unit at||84 MW initial||90 MW current|
|Total installation||426 MW|
|Average annual energy||457,342,000 kilowatt-hours|
|Generator rating||90% pf, units 1-4; 95% pf, unit 5||66,000 kva|
|Generator speed||100 rpm|
|Generator voltage||13.8 kV|
|Transformer rating||two 3-phase||56.6 mva|
|Transformer voltages, kV||13.2 to 230|
|Location west (Georgia) bank, downstream|
|Initial number of transformer bays||2|
|Ultimate number of transformer bays||3|
|Equipment voltage||230 kV|