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Cumberland River Basin2007 Hydrologic & Hydraulic Drought

Joy Broach – Aquatic BiologistPlanning Branch - Environmental Section

SWPBATennessee

November 15-17, 2011

Hydrologic DroughtTDEC Drought Management Plan 2008

Hydrologic Drought (Meteorological) extreme low stream flowsdeclininggroundwater levels

Caused by extended period of reduced precipitation

Hydraulic DroughtTDEC Drought Management Plan 2008

(Hydraulic) Socioeconomic drought - occurs when the demand for goods or services exceeds the available supply as a result of precipitation conditions. Measured by the amount of water available in rivers and lakesImpacts: Hydroelectric Generation Water Supply Navigation (Light Loading & Windows)

Agricultural DroughtTDEC Drought Management Plan 2008

InsufficientSoil Moisture to meet crop needs during growing season

(Alabama State Climatologist) 96 % of the state reported short to very short soil moisture – Oaks dying on ridges – Serious Impacts next 2 years

Palmer Z Index

Short-TermConditions

August 2007

DroughtConditions

StandardizedPrecipitationIndex

Nine Months

December 2006 – August 2007

DroughtConditions

Tennessee DroughtConditions

SOUTHCAROLINA

Laurel

Martins Fork

Wolf Creek

Dale Hollow

CenterHill

J. PercyPriest

Nashville

Cordell HullOld

HickoryCheatham

Barkley

TENNESSEE

KENTUCKY

MISSISSIPPI ALABAMA GEORGIA

NORTHCAROLINA

Lock & DamDam

Mississippi R. Ohio R.

Cumberland R.

Tennessee R.

Cumberland River Basin

VIRGINIA

Nashville District BoundaryHydraulic Drought

Barkley

Cheatham

J. Percy Priest

■Clarksville

■NashvilleCarthage■

■Celina

Center Hill

Old Hickory

Cordell Hull Dale

Hollow

Martins Fork

Laurel

Wolf Creek

Run-of-RiverFlood Damage Reduction

Cumberland River Basin Reservoir System

Interim Risk Reduction Measures

Public and Ecosystem HealthWolf Creek (Lake Cumberland)

– 19 January 2007– Flat-line elevation 680 (Normal Summer Pool 723)

Center Hill– 21 December 2006– June 1 elevation of 640.6 (Normal Summer Pool 648)

Available Storage1 June 2007

ProjectHeadwater

(feet)Available Storage

(Acre-feet)% of Normal

(%)

Wolf Creek 680.5 18,900 1

Dale Hollow 652.1 527,200 106

Center Hill 639.8 346,700 71

J. Percy Priest 489.4 0 0

Total 892,800 28

Wolf CreekWolf Creek

Headwater Elevation2007

670

680

690

700

710

720

730

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Disc

harg

e, cf

s

Headwater Elevation Top of Power Pool SEPA TopSEPA Bottom Seepage Top Seepage Bottom

Wolf Creek Dam Lake Cumberland

Wolf Creek Dam:– Cumberland River Mile 460.9– Completion Date - August 1952– Power Plant - Six 45-MW units– Drainage Area - 5,789 mi2– Surface Area - 50,250 acres– Backwater Length - 101.3 miles– Average Depth - 80 ft– Retention Time - 140 days – Wolf Creek National Fish Hatchery

Pumping System for Wolf Creek Hatchery

Center Hill Lake

Center Hill Dam:– Caney Fork River Mile 26.6– Completion Date - April 1951– Powerplant - Three 45-MW units– Drainage Area - 2,174 mi2– Surface Area - 18,220 acres– Backwater Length - 64.0 miles– Average Depth - 73 ft– Retention Time - 131 days

Center HillCenter Hill

Headwater Elevation2007

620

625

630

635

640

645

650

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Disc

harg

e, cf

s

Headwater Elevation Top of Power Pool SEPA TopSEPA Bottom Seepage Top Seepage Bottom

Cumberland River BasinRainfall Summary

December 2006 - October 2007

01234567

DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT

Rai

nfal

l, in

.

Average Rainfall Observed Rainfall

Cumberland River BasinRunoff Summary

December 2006 - October 2007

0123456

DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT

Run

off,

in.

Average Runoff Observed Runoff

Cumberland River Basin Drought Contingency Plan

Cumberland River Basin Drought Contingency Plan– Dated November 1994– Response to drought of 1985 -1988

System-wide Priorities– Water Supply– Water Quality (Human and Ecosystem Health)– Navigation– Hydropower– Recreation

Old Hickory Dam Releases

0

5000

10000

15000

20000

25000

APR MAY JUN JUL AUG SEP OCT NOV DEC

Median Water Quality 1988 2007

Water QualityWolf Creek Dam Sluice Gate

1,500 cfs

Water QualityWolf Creek Dam Orifice Gate

200 cfs

Water Quality Center Hill Sluice Releases

Sluice Gate Release

►Flow ~ 1,500 cfs►DO >> 10 mg/l

Orifice Gate Release►Flow ~ 200 cfs►DO ~ 9 mg/l

Water Quality Center Hill Orifice Gate Releases

Water Quality Cordell Hull Dam Spillway Releases

Water Quality DataCordell Hull

61 64 68 72 75 79 82 86F F

CORDELL HULL FOREBAY

CORDELL HULL FOREBAY

61 64 68 72 75 79 82 86

TVA Gallatin Fossil Fuel Plant

StationsCRM 241CRM 245

244

243

242

Old Hickory DamSpillway Releases

Old Hickory Water Quality Data

F 72 75 79 82 86 90

F 72 75 79 82 86 90

OLD HICKORYFOREBAY

OLD HICKORYFOREBAY

Spillway Releases at J. Percy Priest Dam

Cheatham DamSpillway Releases

95

86

77

Tem

pera

ture

(OF)

68

59

50

41

TVA Cumberland Fossil Fuel Plant

StationsCRM 100.1CRM 105.5

103

103

ALMS GA

TN NC

KY VA

Summary of ConcernsHot, dry conditions accelerate evaporation rates (little or no runoff)Ability to support water supply in Lake Cumberland and downstream

– Quantity – Quality Wolf Creek and Center Hill coldwater fisheriesWater quality at Cordell Hull, Old Hickory, and CheathamVulnerability of river system to a wastewater bypass eventCooling water requirements at Gallatin and Cumberland CityMaintain commercial navigation in some capacityTributary projects at near record low elevations

Questions?

Answer: It depends on the weather.

Cumberland River Basin2007 Hydrologic & Hydraulic Drought