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Martin Rule Curve StudyMartin Rule Curve Study
Ashley McVicar, APCAshley McVicar, APC
Maurice James, Water Resources Maurice James, Water Resources Consulting LLC Consulting LLC
Martin Rule Curve StudyMartin Rule Curve Study
PurposePurpose Preliminary modeling study to determine the Preliminary modeling study to determine the
feasibility of a higher winter pool at Martin in feasibility of a higher winter pool at Martin in accordance with MIG 3 Project Operations accordance with MIG 3 Project Operations Study Plan.Study Plan.
Martin Rule Curve StudyMartin Rule Curve Study
Design Flood Study ApproachDesign Flood Study Approach Determine historical flood event to model for Determine historical flood event to model for
the 100 year design flood the 100 year design flood Replicate operations for the actual flood event Replicate operations for the actual flood event
in an operation spreadsheetin an operation spreadsheet Evaluate a higher winter pool vs. baseline of Evaluate a higher winter pool vs. baseline of
elevation 480’elevation 480’ Compare ResultsCompare Results
““100 Year Flood”100 Year Flood” Has a specific definitionHas a specific definition
US Dept of Interior Bulletin 17BUS Dept of Interior Bulletin 17B
Applied by Regulating Agencies (FEMA, Applied by Regulating Agencies (FEMA, COE, FERC, the States, etc.)COE, FERC, the States, etc.)
Frequency Analysis of Maximum Annual Frequency Analysis of Maximum Annual Flood Events.Flood Events.
1% chance of occurrence in each year.1% chance of occurrence in each year. Generally concerned with peak flowGenerally concerned with peak flow For Reservoirs – volume also criticalFor Reservoirs – volume also critical
How is this Analysis Done?How is this Analysis Done?
Select Maximum Flood Event for each Select Maximum Flood Event for each year.year. Prefer 30+ year record.Prefer 30+ year record.
Apply a specific frequency analysis to Apply a specific frequency analysis to data. data. COE Frequency Analysis programCOE Frequency Analysis program Project to 1% probability of exceedence.Project to 1% probability of exceedence.
Monthly AnalysisMonthly Analysis
Not an established procedure.Not an established procedure. Referred to as a “Partial Duration”Referred to as a “Partial Duration”
Only considering part of the record.Only considering part of the record. Maximum event in month for the period Maximum event in month for the period
of record.of record. Annual peak procedures may not apply.Annual peak procedures may not apply. Will still have a probability of exceedence Will still have a probability of exceedence
but not necessarily 1%.but not necessarily 1%.
Horseshoebend Annual Peaks
0%
5%
10%
15%
20%
25%
30%
35%
1 2 3 4 5 6 7 8 9 10 11 12
Month
Perc
en
t
19 Years of Record
Approximate Rule Curve
EL 480 ft.
EL 490 ft.
74%
Probability
0.9999 0.9990 0.9900 0.9000 0.5000 0.1000 0.0100 0.0010 0.0001
Flow
(cf
s)
100.0
1000.0
10000.0
100000.0
Exceedance Probability for Martin DEC Freq Analysis
DEC-MON Observed Events (Weibull plotting positions)
Computed Curve
Expected Probability Curve
5 Percent Confidence Limit
95 Percent Confidence Limit
What does all this say?What does all this say?
There is a chance that the 100 year flood There is a chance that the 100 year flood could occur in any month of the year.could occur in any month of the year.
The greatest chance would be during the The greatest chance would be during the months of Dec. through April.months of Dec. through April.
Not necessary for the record to have an Not necessary for the record to have an event near or greater than the 1% event.event near or greater than the 1% event.
Martin Rule Curve StudyMartin Rule Curve Study
APC Flood Frequency AnalysisAPC Flood Frequency Analysis Model developed by COE – Hydrologic Model developed by COE – Hydrologic
Engineering Center in Davis, CAEngineering Center in Davis, CA Utilizes the COE 1939-2001 unimpaired flow Utilizes the COE 1939-2001 unimpaired flow
database created as part of the ACT database created as part of the ACT Comprehensive StudyComprehensive Study
Submitted to the COE by APC in November Submitted to the COE by APC in November 20052005
Martin Rule Curve StudyMartin Rule Curve Study
Martin flowMartin flow 100 yr flow unregulated = 130,000 cfs-days100 yr flow unregulated = 130,000 cfs-days March 1990 flow unregulated = 125,019 cfs-March 1990 flow unregulated = 125,019 cfs-
days (96% of 100 year flood)days (96% of 100 year flood) March 1990 inflow regulated used in Martin March 1990 inflow regulated used in Martin
Rule Curve evaluation (with Harris and Martin Rule Curve evaluation (with Harris and Martin in place) = 92,307 cfs-days (71% of 100 year in place) = 92,307 cfs-days (71% of 100 year unregulated flood)unregulated flood)
Basin Wide RainfallBasin Wide Rainfall
Current Martin Flood Control Current Martin Flood Control Guidelines Pre-Turbine UpgradesGuidelines Pre-Turbine Upgrades
Martin Rule Curve Study Martin Rule Curve Study Post Turbine UpgradesPost Turbine Upgrades
General AssumptionsGeneral Assumptions Martin Turbine Capacity = 16500 (based on Martin Turbine Capacity = 16500 (based on
upgrades completed in 2004)upgrades completed in 2004) Yates Turbine Capacity = 12400Yates Turbine Capacity = 12400 Thurlow Turbine Capacity = 13200Thurlow Turbine Capacity = 13200 20 spillway gates 20 spillway gates Ability to open 2 spillway gates an hour Ability to open 2 spillway gates an hour
Martin Reservoir Model Calibration
-
20,000
40,000
60,000
80,000
100,000
120,000
140,000
3/15 3/16 3/17 3/18 3/19 3/20 3/21 3/22 3/23 3/24
Date
Dis
char
ge
cfs
483.0
484.0
485.0
486.0
487.0
488.0
489.0
490.0
Ele
vati
on
ft.
(M
arti
n D
atu
m)
Model Discharge
Actual Discharge
Inflow
Model Elevation
Actual Elevation
Martin Rule Curve StudyMartin Rule Curve Study
Design Flood EvaluationDesign Flood Evaluation Operational criteria set forth in model Operational criteria set forth in model
accurately replicated historical conditionsaccurately replicated historical conditions
Martin Rule Curve StudyMartin Rule Curve Study
Evaluation of Winter Pool of 480’ vs. 483’Evaluation of Winter Pool of 480’ vs. 483’ Used current operational criteria set forth by Used current operational criteria set forth by
March 1990 flood historical operations and March 1990 flood historical operations and began pool at both 480’ and 483’began pool at both 480’ and 483’
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Martin Reservoir 480 vs. 483 Model Simulation
-
20,000
40,000
60,000
80,000
100,000
120,000
140,000
15 16 17 18 19 20 21 22 23 24
Date
Dis
char
ge
cfs
478
480
482
484
486
488
490
492
Ele
vati
on
ft.
(M
arti
n D
atu
m)
480 Discharge
483 Discharge
Inflow
480 Elevation
483 Elevation
Martin Rule Curve StudyMartin Rule Curve Study
Elevation 480’ vs 483’ ResultsElevation 480’ vs 483’ Results Martin pool kept below top of easement Martin pool kept below top of easement
elevation 490 for both elevation 490 for both Beginning winter pool elevation of 483’ results Beginning winter pool elevation of 483’ results
in earlier releases as well as approximately in earlier releases as well as approximately 25-30k higher discharge during the peak25-30k higher discharge during the peak
Resulting outflows passed downstream Resulting outflows passed downstream with HEC-RAS model with HEC-RAS model
Tallapoosa Profile
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
0 5 10 15 20 25 30 35 40 45 50 55
Tallapoosa River Mile
Max
imu
m E
leva
tio
n f
t. m
sl Initial Pool-480
Initial Pool-483Montgomery Water
Works gage
Milestead gage
Tallassee gage
Alabama River Thurlow Dam
Martin Rule Curve StudyMartin Rule Curve Study
ResultsResults Elevations downstream result in a 1’ – 3’ Elevations downstream result in a 1’ – 3’
higher elevation downstream to Alabama higher elevation downstream to Alabama River.River.
COE uses FEMA’s requirement of “no COE uses FEMA’s requirement of “no increase of peak elevation downstream”increase of peak elevation downstream”
FERC defers to the COE for flood analysisFERC defers to the COE for flood analysis FERC would require a full analysis of flood, FERC would require a full analysis of flood,
environmental and recreational impacts of environmental and recreational impacts of proposed vs. current operation proposed vs. current operation
Martin Rule Curve StudyMartin Rule Curve Study
Further Study during Relicensing RequiredFurther Study during Relicensing Required MIG 3 proposals evaluatedMIG 3 proposals evaluated Look at different winter pool elevation and/or shape of Look at different winter pool elevation and/or shape of
Rule Curve Rule Curve Look at different operational plansLook at different operational plans Further evaluate downstream flood & environmental Further evaluate downstream flood & environmental
impacts and present these effects and associated impacts and present these effects and associated mitigation measures to FERCmitigation measures to FERC
FERC will then evaluate and balance all interestsFERC will then evaluate and balance all interests