ML20080M136
| ML20080M136 | |
| Person / Time | |
|---|---|
| Issue date: | 03/23/2020 |
| From: | M'Lita Carr, Harden T, O'Connor J Office of Nuclear Regulatory Research, US Dept of Interior, Geological Survey (USGS), US Dept of Interior, Geological Survey, Oregon Water Science Center |
| To: | Office of Nuclear Regulatory Research |
| T. Aird | |
| Shared Package | |
| ML20080M135 | List: |
| References | |
| Download: ML20080M136 (30) | |
Text
Tess Harden - USGS Oregon Water Science Center Jim OConnor - USGS Geology, Mineral, Energy and Geophysics Meredith Carr - Nuclear Regulatory Commission
What is Paleoflood Hydrology
.using geologic evidence to understand flood history
Harden and OConnor, 2017 Tennessee River Gorge Chattanooga
Reworked flood deposit 1917??
Burrow fill Flood deposit Flood deposit 14C 360+/-30 Local material 14C 2210+/-30 Provisional data, do not cite
Identified ~30 sites, fully described 17 Focused on sites were preservation of sediment was most ideal Also targeted a full range of site elevations Radiocarbon dating and optically stimulated luminescence (OSL)
Tennessee Valley Authority Naturals model in HEC-RAS shortened to provide sufficient length for boundary conditions.
Calibrated to historical high water marks.
i o Oh
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nd e rl a 44.314*
52.468*
um C
60.538* b ls Ho 68.232* Barkley-Ohio on t
SFHols ton-77.34*
85.7033* 79.795 66.07* 52.29 95.1375* NOH-Tenn 103.46* 47.725*15.005*
Nolichucky-Tenn 652.22 8.4 Forks 32.2 of River 115.606* 8.4 29.55*
568.11*
0 Hols ton-LilTenn 630.12 123.87* Clinch 546.94 2.65333*
LilTenn-Clinch 594.845*
Little Tenn 132.82* Clinch-Hiwass ee 530.96* 12.7885*
140.718* 516.93* 33.595 150.902* FNH-Tenn 500.75*
176.32* Hiwass ee 12.7066*
es 492.04 Hiwass ee-Elk 192.41*
se El k 30.52 Ocoee-Tenn 483.095*
1.2 53.8 n ee Te n o
200.897*
e Te n 22 471.793* Oc 11.88 Nottely-Ocoee 213.73* TFH-Tenn 434.6 16 36.51 n se 20 19 205 204 425.72 BaySprings 227.8 se 1718 207 20621 BRH-Hiwas s ee 22.35 406.297*
239.4258.8 278.777*
2.61285*
Elk-Ohio e
396.31*
Ocoee Elk 295.059* 386.85 309.44 374.23 337.352*
o-Ref ef Non 49 us Non Geo-Ref er XS'sinterpolated entered Geo-Ref are usGeo-Referenced not XS er interpolated XS entered XSXS) ( 363.72
TVA, 1940
8 unique paleofloods in ~4,000 years Bulletin 17C EMA LP3 distribution Discharge uncertainty and perception thresholds USGS PeakFQ England and others, 2019
Benito et al., (in press)
Perception thresholds (17C; England et al., 2019):
- The stage or flow above which a source would provide information on the flood peak in any given year.
- Reflect the range of flows that would have been measured had they occurred
Scenario 1: Gaged plus historical record (1826-2008), 3 perception thresholds Scenario 2-4: 4 paleofloods (350,1000, 1500, 1650); 5 perception thresholds (variation to 1 paleo perception threshold)
Scenario 5-7: 4 paleofloods (variation in age and magnitude); 5 perception thresholds
4 paleofloods used in the flood frequency analysis.
Age and magnitude was varied in some scenarios to account geochronologic and stratigraphic uncertainty.
Missing year Provisional data, do not cite Historical: 1826-1873 Gage: 1874-2008
Red Flower Perception flood age threshold change varies Discharge, cfs A.D. 1000 Perception flood threshold magnitude varies change Perception Red Flower flood threshold magnitude varies change Year Provisional data, do not cite
Discharge, cfs Best estimate
~4000 year record 4 paleofloods and 5 perception thresholds Year Provisional data, do not cite
Gaged + historical data Provisional data, do not cite
Best estimate
~4000 year record 4 paleofloods and 5 perception thresholds Provisional data, do not cite
Provisional data, do not cite Gaged + historical record Scenario 1: Gaged and Historical Record Scenario 5: 4 Paleofloods (Red Flower A.D. 1050),
PT1A-PT5 Return EMA Confidence Limits AEP Return EMA Confidence Limits Period Estimate AEP Lower Upper Period Estimate Lower Upper 100 0.01 370000 340000 450000 100 0.01 400000 370000 440000 200 0.005 390000 350000 490000 200 0.005 440000 400000 480000 500 0.002 430000 370000 560000 500 0.002 490000 450000 560000 1,000 0.001 460000 380000 610000 1,000 0.001 540300 480000 620000 10,000 0.0001 520000 410000 800000 10,000 0.0001 700900 600000 900000 Scenario 3: 4 Paleofloods, PT1A-PT5, Best Estimate Scenario 7: 4 Paleofloods (Red Flower flood discharge equal to that of Jeff-n-Steph flood), PT1A-Return EMA Confidence Limits AEP PT5 Period Estimate Lower Upper Return EMA Confidence Limits AEP Period Estimate Lower Upper 100 0.01 400000 370000 430000 100 0.01 400000 360000 420000 200 0.005 440000 400000 480000 200 0.005 420000 390000 450000 500 0.002 500000 450000 560000 500 0.002 460000 420000 500000 1,000 0.001 540000 480000 620000 1,000 0.001 490000 440000 540000 10,000 0.0001 700000 600000 900000 10,000 0.0001 580000 510000 690000 Best Estimate Paleoflood Scenario Provisional data, do not cite
Change date of large Red Flower flood Scenario 1: Gaged and Historical Record Scenario 5: 4 Paleofloods (Red Flower A.D. 1050),
PT1A-PT5 Return EMA Confidence Limits AEP Return EMA Confidence Limits Period Estimate AEP Lower Upper Period Estimate Lower Upper 100 0.01 370000 340000 450000 100 0.01 400000 370000 440000 200 0.005 390000 350000 490000 200 0.005 440000 400000 480000 500 0.002 430000 370000 560000 500 0.002 490000 450000 560000 1,000 0.001 460000 380000 610000 1,000 0.001 540300 480000 620000 10,000 0.0001 520000 410000 800000 10,000 0.0001 700900 600000 900000 Scenario 3: 4 Paleofloods, PT1A-PT5, Best Estimate Scenario 7: 4 Paleofloods (Red Flower flood discharge equal to that of Jeff-n-Steph flood), PT1A-Return EMA Confidence Limits AEP PT5 Period Estimate Lower Upper Return EMA Confidence Limits AEP Period Estimate Lower Upper 100 0.01 400000 370000 430000 100 0.01 400000 360000 420000 200 0.005 440000 400000 480000 200 0.005 420000 390000 450000 500 0.002 500000 450000 560000 500 0.002 460000 420000 500000 1,000 0.001 540000 480000 620000 1,000 0.001 490000 440000 540000 10,000 0.0001 700000 600000 900000 10,000 0.0001 580000 510000 690000 Best Estimate Paleoflood Scenario Provisional data, do not cite
Gaged plus historical record Provisional data, do not cite Scenario 1: Gaged and Historical Record Scenario 5: 4 Paleofloods (Red Flower A.D. 1050),
PT1A-PT5 Return EMA Confidence Limits AEP Return EMA Confidence Limits Period Estimate AEP Lower Upper Period Estimate Lower Upper 100 0.01 370000 340000 450000 100 0.01 400000 370000 440000 200 0.005 390000 350000 490000 200 0.005 440000 400000 480000 500 0.002 430000 370000 560000 500 0.002 490000 450000 560000 1,000 0.001 460000 380000 610000 1,000 0.001 540300 480000 620000 10,000 0.0001 520000 410000 800000 10,000 0.0001 700900 600000 900000 Scenario 3: 4 Paleofloods, PT1A-PT5, Best Estimate Scenario 7: 4 Paleofloods (Red Flower flood discharge equal to that of Jeff-n-Steph flood), PT1A-Return EMA Confidence Limits AEP PT5 Period Estimate Lower Upper Return EMA Confidence Limits AEP Period Estimate Lower Upper 100 0.01 400000 370000 430000 100 0.01 400000 360000 420000 200 0.005 440000 400000 480000 200 0.005 420000 390000 450000 500 0.002 500000 450000 560000 500 0.002 460000 420000 500000 1,000 0.001 540000 480000 620000 1,000 0.001 490000 440000 540000 10,000 0.0001 700000 600000 900000 10,000 0.0001 580000 510000 690000 Best Estimate Paleoflood Scenario Change magnitude of large Red Flower flood
Adding 4000 years of paleoflood data reduces uncertainty of the very small AEPs by 22-44%
Adding 4000 years of paleoflood data increases the magnitude of the very small AEPs.
Record length has a strong influence on the curve.
Provisional data, do not cite