Ballestero, Thomas P.

Roseen, Robert M.

Scholz, Ann

English

University of New Hampshire

University of New Hampshire
University of New Hampshire Scholars' Repository
UNH Stormwater Center Research Institutes, Centers and Programs
3-21-2012
Climate and Land Use Consequences to 100-Year
Flooding
Robert M. Roseen
University of New Hampshire
Ann Scholz
University of New Hampshire
Thomas P. Ballestero
University of New Hampshire, tom.ballestero@unh.edu
Follow this and additional works at: https://scholars.unh.edu/stormwater
This Presentation is brought to you for free and open access by the Research Institutes, Centers and Programs at University of New Hampshire
Scholars' Repository. It has been accepted for inclusion in UNH Stormwater Center by an authorized administrator of University of New Hampshire
Scholars' Repository. For more information, please contact nicole.hentz@unh.edu.
Recommended Citation
Roseen, Robert M.; Scholz, Ann; and Ballestero, Thomas P., "Climate and Land Use Consequences to 100-Year Flooding" (2012).
Lamprey River 100 Year Flood Risk Projecthttp://100yearfloods.org. 57.
https://scholars.unh.edu/stormwater/57
Climate and Land Use Consequences to 
100-Year Flooding 
Robert Roseen D.WRE, PE, PhD, Ann Scholz, PE, CPSWQ, 
Thomas Ballestero, PhD, PE, PH, UNH Stormwater Center 
Nebraska Post- Construction Stormwater Workshop 
Lincoln, Nebraska 
March 21, 2012 
Lamprey River 100 Year Flood Risk Project 
Two year project funded by the  Cooperative Institute  for 
Coastal and Estuarine Environmental Technology (CICEET) 
Interdisciplinary Team: 
Robert Roseen, Ann Scholz, Thomas Ballestero, UNH Stormwater Center 
Cameron Wake, Institute for the Study of Earth, Oceans and Space, UNH 
Steve Miller, Great Bay National Estuarine Research Reserve 
Kathy Mills, Great Bay National Estuarine Research Reserve 
Fay Rubin, Institute for the Study of Earth, Oceans and Space, UNH 
Michael Simpson, Antioch University New England 
Lisa Townson and Julia Peterson, UNH Cooperative Extension 
1.  Failure to think globally and act locally-We must account for 
climate change 
2.  Failure to absorb new knowledge 
3.  Failure to understand, manage, and communicate risk-Need 
to take rigorous risk based approach,  
4.  Failure to build quality in 
5.  Failure to build in resilience 
6.  Failure to provide redundancy  
7.  Failure to see that the sum of many parts does not equal a 
system 
8.  The buck couldn’t find a place to stop--Poor organization, 
lack of accountability 
9.  Beware of interfaces: materials and jurisdiction 
10.  Follow the money-People responsible for design and 
construction had no control of the monies. 
4!

6 
15 Highest Events –  
Peak Recorded Discharges on Lamprey River 
Of 15 largest events since 1934:!
  8 have occurred in last 25 years!
  5 have occurred in last  15 years!
  3 have occurred in last  5 years!
Rank% Date%
Discharge%
(cfs)%
1% 164May406% 8,970%
2% 184Apr407% 8,450%
3% 74Apr487% 7,570%
4% 224Oct496% 7,080%
5% 154Mar410% 6,760%
6% 204Mar436% 5,490%
7% 154Mar477% 5,000%
8% 154June498% 4,720%
9% 34Apr404% 4,690%
10% 304Mar483% 4,570%
11% 64Apr460% 4,470%
12% 114May454% 4,070%
13% 24Feb481% 3,670%
14% 314July438% 3,530%
15% 14Apr493% 3,400%
Source:  http://
waterdata.usgs.gov/nwis 
FIS: 7300 cfs =100-Yr Flood Flow!
CAUSES 
  Land Use ChangesIncrease in 
impervious cover 
  Changes in storm depth, 
duration, and 
frequencyIncreased rainfall 
depth and runoff volume 
SOLUTIONS 
  Land use management 
strategies to mitigate runoff 
volumes 
7!
The use of LID planning and technologies 
can contribute to building community 
resiliency in managing water resources 
and reduce the flood risk associated with 
current and projected changes in land use 
and climate.  
8!
Hydrologic Model Scenarios!
9!
Project(Models%
Land%Use%
CondiMons%
Rainfall%Rates%and%Global%Change%Model%Scenario%
Rainfall%Atlas%
Climate%Period%
203542069%
Climate%Period%
207042099%
TP440% NRCC% NRCC% Regional%Model%
6.3%in/hr% 8.5%in/hr% 8.5%in/hr% X%in/hr%
Current% 2005% 2005%
Build4out% 2050% 2085%
LID/Build4out% 2050% 2085%
Lamprey River 
Watershed 
10!
FEMA Requirements for 
Redelineation 
• Hydrologic Analysis:!
o  Bulletin 17B for gaged streams!
! !Effective Model – 1935 through 1987 !
! ! ! ! !Q100 = 7,300 cfs!
o  Criteria for revised hydrologic analysis!
 Statistically Significance (68-percent confidence interval) !
! !L0.01,0.68 = 6,886 cfs  H0.01,0.68  = 7,834 cfs !!
! !!
 75 yr record – 1935 - 2009!
! !Q100 = 9,411 cfs !!
! !Statistically Significant!
11!
Subbasin% Area%(mi2)%
%%W6510% 32.2%
%%W8600% 19.0%
%%W11900% 16.0%
%%W10910% 6.5%
%%W8380% 12.3%
%%W11020% 6.1%
%%W6730% 58.3%
%%W7060% 33.9%
%%W7920% 4.5%
%%W10250% 21.7%
%%W8590% 0.9%
Total% 211.7%
W7060 
W6730 
W8590 
W10910 
W8380 
W11900 
W6510 
W7920 
W10250 
12 
W8600 
W11020 
Subbasin% CN%
%%W6510% 62.5%
%%W8600% 63.0%
%%W11900% 64.2%
%%W10910% 61.2%
%%W8380% 63.5%
%%W11020% 62.5%
%%W6730% 65.4%
%%W7060% 63.9%
%%W7920% 67.7%
%%W10250% 66.0%
%%W8590% 71.0%
13 
W7060 
W6730 
W8590 
W10910 
W8380 
W11900 
W6510 
W7920 
W10250 
W8600 
W11020 
14!
Current Conditions, 
‘CN’ = 66.8!
Conventional  Build-Out, 
‘CN’ = 78.0!
LID Build-Out!
‘CN’ = 69.5!
15!
Commercial Zoning!
One Acre Residential!
Runoff Curve Number Reduction Method from : 1. McCuen, R. and M. D. E. (1983). Changes in Runoff Curve Number Method; 2. Maryland Department of Environment  (2008). Maryland Stormwater Design Manual, 
Supplement No. 1.!
16 
Summary%of%Cross%SecMon%Data%Source%
Source% Number%
FEMA%FIS%Backup%Data% 111%
%%%%%Duplicates% 19%
Surveyed% 12%
NHDOT/Consultants% 34%
GIS% 44%
Total% 220%
Hydraulics Model – Results for RT108!
April 2007 WSE = 34.41 
March 2010 WSE =33.58 
1
8 
NRCC 100-YR WSE = 35.83 
FIS WSE = 33.0 
Observed WSE: 
April 2007 – 34.1 
March 2010 – 33.3 
Hydraulics Model – Results and Calibration for RT108!
  Model updates indicated a 45% increase in 
the 100-year flood flow from  
◦  USGS gage: 7,300 cfs (FIS) to 10,649 cfs (NRCC) 
  An increase in the base flood elevations by an 
average of 2.7 feet along the 36 mile study 
reach.  
   NRCC elevation almost two feet higher than April 2007 event 
Watershed Scale Build-Out 
  Conventional development resulted in an increase 0.3 
feet in base flood elevation and a 4.3% flood flow 
increase and only a 2.8% increase with the LID 
scenario.   
Subwatershed Scale Build-Out 
  Urban sub basins had substantial runoff reductions 
using LID build-out scenarios and in one instance 
actually reduced beyond current conditions.  
  Conventional build-out had increases in runoff from 
29-36% whereas LID build-out had a range of -2-7%.  
This last finding is substantial illustrates that LID in a redevelopment 
scenario can serve to reduce runoff from current conditions.!
Funding 
Funding is provided  by the Cooperative Institute for Coastal and 
Estuarine Environmental Technology (CICEET) whose mission is to 
support the scientific development of innovative technologies for 
understanding and reversing the impacts of coastal and estuarine 
contamination and degradation. 

Hydraulics Model – Cross Sections!
23!
Summary%of%Cross%SecMon%Data%Source%
Source% Number%
FEMA%FIS%Backup%Data% 111%
%%%%%Duplicates% 19%
Surveyed% 12%
NHDOT/Consultants% 34%
GIS% 44%
Total( 220(
•  FIS sections were duplicated as needed to provide immediate 
sections up and downstream of bridges!
•  No backup data available for Lee!
•  Projects included additional sections supplementing FIS sections!
•  Improved modeling in RT108 corridor and tributaries!
Hydraulics Model – Structural Data!
24!
Summary%of%Bridge%Structure%Source%for%the%Lamprey%River%
Community% StaMon% Road%Name% Data%Source%
Raymond% 181300% Dudley%Road%
Electronic%WSP2%files%from%Roald%Haestad,%Inc.%
March%1993%
180964% Raymond%Road%(RT%27)%
167900% Langford%Road%
160746% Main%Street%
155060% Epping%Street%
154106% B&M%Railroad%
147643% Freetown%Road%(RT%107)%
141372% Presco`%Road%
Epping% 136759% State%Route%101%
127937% Epping%Road%(RT%27)% Electronic%HEC4RAS%files%from%NHDOT,%2010%
123964% Blake%Road%
As4built%drawings%from%NHDOT,%dates%vary%
107459% Main%Street%(Plummer)%
106269% Mill%Street%
Electronic%HEC4RAS%files%from%NHDOT,%2000%
105560% Calef%Hwy%(RT%125)%
88171% Hedding%Road%(RT%87)% WSPRO%print%out%and%As4built%from%NHDOT,%2000%
Lee% 61457% Wadleigh%Falls%Road%
As4built%drawings%from%NHDOT,%dates%vary%
35683% Lee%Hook%Road%
Durham% 20082% Wiswall%Road% Electronic%HEC4RAS%files%from%CLD%ConsulMng,%2009%
16028% Packer's%Falls%Road%
FEMA%FIS%Backup%Data%
Newmarket% 1602% RT%108%
Summary%of%Bridge%Structure%Source%for%the%RT108%Corridor%
Watercourse% StaMon% Road%Name% Data%Source%
Floodplain% 71% Newmarket%Road%(RT%108)% Survey%drawings%from%NHDOT,%2010%
Hamil%Brook% 1040% Newmarket%Road%(RT%108)%
FEMA%FIS%Backup%Data%
Longmarsh%Brook% 4182% Bedard%Road%
Longmarsh%Brook% 1703% Longmarsh%Road%
Longmarsh%Brook% 275% Tote%Road%
Hydraulics Model – Dam and In-line Structural Data!
25!
Summary%of%In4line%Structure%Source%for%the%Lamprey%River%
Community% StaMon% Road%Name% Data%Source%
Epping% 127265% Bunker%Pond%Dam% Electronic%HEC4RAS%files%from%NHDOT%
Lee% 61266% Wadleigh%Falls%Dam% Land%Records%
Durham% 19859% Wiswall%Dam% Electronic%HEC4RAS%files%from%CLD%
ConsulMng%Engineers%
Newmarket% 1286% Coffee%Sluice%
Electronic%HEC4RAS%files%from%Wright4Pierce%
Newmarket% 1164% Macallen%Dam%
•  NHDES Dam Management studying removal of Bunker Pond dam!
•  Wiswall bridge has been replaced and downstream dam 
replacement in near future!
•  Macallen Dam recently inspected per NHDES request !
•  Spillway dimensions and layout, elevation field verified!
• Calibration:!
o  April 2007 – 7,590 cfs, Precipitation – 7.65 in!
o  March 2010 – 6,550 cfs, Precipitation – 7.02 in!
• Optimization parameters:!
o  Manning’s ‘n’!
o  Lag Time!
o  Tc!
• Simulated for !
o  Time to peak!
o  Runoff volume!
o  Peak flow!
Calibrating the Watershed 
2
6 
Calibrating the Watershed 
2
7 
Calibrating the Watershed 
28!
Hydrology Model – Calculated flood flow for the gaged 183 sq.mi. 
watershed !
•  Results of calibrated model run for current land use (2005) using 
TP-40 rainfall. !Q100, TP-40 = 7,580 cfs  vs. Q100, FIS = 7,300 cfs !
•  Results of calibrated model run for current land use (2005) using 
NRCC Atlas rainfall. !Q100, CA = 10,649 cfs!
•  68-percent confidence interval of gaging station estimate for data 
from 1935-2009, !Q100, LP3 = 9,411 cfs!
!L0.01,0.68 = 8,862 cfs     H0.01,0.68  = 10,040 cfs!
29!
Calibrating the Watershed 


Climate and Land Use Consequences to
 100-Year Flooding

UNH Scholars' Repository

University of New HampshireUniversity of New Hampshire Scholars' RepositoryUNH Stormwater Center Research Institutes, Centers and Programs3-21-2012Climate and Land Use Consequences to 100-YearFloodingRobert M. RoseenUniversity of New HampshireAnn ScholzUniversity of New HampshireThomas P. BallesteroUniversity of New Hampshire, tom.ballestero@unh.eduFollow this and additional works at: https://scholars.unh.edu/stormwaterThis Presentation is brought to you for free and open access by the Research Institutes, Centers and Programs at University of New HampshireScholars' Repository. It has been accepted for inclusion in UNH Stormwater Center by an authorized administrator of University of New HampshireScholars' Repository. For more information, please contact nicole.hentz@unh.edu.Recommended CitationRoseen, Robert M.; Scholz, Ann; and Ballestero, Thomas P., "Climate and Land Use Consequences to 100-Year Flooding" (2012).Lamprey River 100 Year Flood Risk Projecthttp://100yearfloods.org. 57.https://scholars.unh.edu/stormwater/57Climate and Land Use Consequences to 100-Year Flooding Robert Roseen D.WRE, PE, PhD, Ann Scholz, PE, CPSWQ, Thomas Ballestero, PhD, PE, PH, UNH Stormwater Center Nebraska Post- Construction Stormwater Workshop Lincoln, Nebraska March 21, 2012 Lamprey River 100 Year Flood Risk Project Two year project funded by the  Cooperative Institute  for Coastal and Estuarine Environmental Technology (CICEET) Interdisciplinary Team: Robert Roseen, Ann Scholz, Thomas Ballestero, UNH Stormwater Center Cameron Wake, Institute for the Study of Earth, Oceans and Space, UNH Steve Miller, Great Bay National Estuarine Research Reserve Kathy Mills, Great Bay National Estuarine Research Reserve Fay Rubin, Institute for the Study of Earth, Oceans and Space, UNH Michael Simpson, Antioch University New England Lisa Townson and Julia Peterson, UNH Cooperative Extension 1.  Failure to think globally and act locally-We must account for climate change 2.  Failure to absorb new knowledge 3.  Failure to understand, manage, and communicate risk-Need to take rigorous risk based approach,  4.  Failure to build quality in 5.  Failure to build in resilience 6.  Failure to provide redundancy  7.  Failure to see that the sum of many parts does not equal a system 8.  The buck couldn’t find a place to stop--Poor organization, lack of accountability 9.  Beware of interfaces: materials and jurisdiction 10.  Follow the money-People responsible for design and construction had no control of the monies. 4!6 15 Highest Events –  Peak Recorded Discharges on Lamprey River Of 15 largest events since 1934:!  8 have occurred in last 25 years!  5 have occurred in last  15 years!  3 have occurred in last  5 years!Rank% Date%Discharge%(cfs)%1% 164May406% 8,970%2% 184Apr407% 8,450%3% 74Apr487% 7,570%4% 224Oct496% 7,080%5% 154Mar410% 6,760%6% 204Mar436% 5,490%7% 154Mar477% 5,000%8% 154June498% 4,720%9% 34Apr404% 4,690%10% 304Mar483% 4,570%11% 64Apr460% 4,470%12% 114May454% 4,070%13% 24Feb481% 3,670%14% 314July438% 3,530%15% 14Apr493% 3,400%Source:  http://waterdata.usgs.gov/nwis FIS: 7300 cfs =100-Yr Flood Flow!CAUSES   Land Use ChangesIncrease in impervious cover   Changes in storm depth, duration, and frequencyIncreased rainfall depth and runoff volume SOLUTIONS   Land use management strategies to mitigate runoff volumes 7!The use of LID planning and technologies can contribute to building community resiliency in managing water resources and reduce the flood risk associated with current and projected changes in land use and climate.  8!Hydrologic Model Scenarios!9!Project(Models%Land%Use%CondiMons%Rainfall%Rates%and%Global%Change%Model%Scenario%Rainfall%Atlas%Climate%Period%203542069%Climate%Period%207042099%TP440% NRCC% NRCC% Regional%Model%6.3%in/hr% 8.5%in/hr% 8.5%in/hr% X%in/hr%Current% 2005% 2005%Build4out% 2050% 2085%LID/Build4out% 2050% 2085%Lamprey River Watershed 10!FEMA Requirements for Redelineation • Hydrologic Analysis:!o  Bulletin 17B for gaged streams!! !Effective Model – 1935 through 1987 !! ! ! ! !Q100 = 7,300 cfs!o  Criteria for revised hydrologic analysis! Statistically Significance (68-percent confidence interval) !! !L0.01,0.68 = 6,886 cfs  H0.01,0.68  = 7,834 cfs !!! !! 75 yr record – 1935 - 2009!! !Q100 = 9,411 cfs !!! !Statistically Significant! 11!Subbasin% Area%(mi2)%%%W6510% 32.2%%%W8600% 19.0%%%W11900% 16.0%%%W10910% 6.5%%%W8380% 12.3%%%W11020% 6.1%%%W6730% 58.3%%%W7060% 33.9%%%W7920% 4.5%%%W10250% 21.7%%%W8590% 0.9%Total% 211.7%W7060 W6730 W8590 W10910 W8380 W11900 W6510 W7920 W10250 12 W8600 W11020 Subbasin% CN%%%W6510% 62.5%%%W8600% 63.0%%%W11900% 64.2%%%W10910% 61.2%%%W8380% 63.5%%%W11020% 62.5%%%W6730% 65.4%%%W7060% 63.9%%%W7920% 67.7%%%W10250% 66.0%%%W8590% 71.0%13 W7060 W6730 W8590 W10910 W8380 W11900 W6510 W7920 W10250 W8600 W11020 14!Current Conditions, ‘CN’ = 66.8!Conventional  Build-Out, ‘CN’ = 78.0!LID Build-Out!‘CN’ = 69.5!15!Commercial Zoning!One Acre Residential!Runoff Curve Number Reduction Method from : 1. McCuen, R. and M. D. E. (1983). Changes in Runoff Curve Number Method; 2. Maryland Department of Environment  (2008). Maryland Stormwater Design Manual, Supplement No. 1.!16 Summary%of%Cross%SecMon%Data%Source%Source% Number%FEMA%FIS%Backup%Data% 111%%%%%%Duplicates% 19%Surveyed% 12%NHDOT/Consultants% 34%GIS% 44%Total% 220%Hydraulics Model – Results for RT108!April 2007 WSE = 34.41 March 2010 WSE =33.58 18 NRCC 100-YR WSE = 35.83 FIS WSE = 33.0 Observed WSE: April 2007 – 34.1 March 2010 – 33.3 Hydraulics Model – Results and Calibration for RT108!  Model updates indicated a 45% increase in the 100-year flood flow from  ◦  USGS gage: 7,300 cfs (FIS) to 10,649 cfs (NRCC)   An increase in the base flood elevations by an average of 2.7 feet along the 36 mile study reach.     NRCC elevation almost two feet higher than April 2007 event Watershed Scale Build-Out   Conventional development resulted in an increase 0.3 feet in base flood elevation and a 4.3% flood flow increase and only a 2.8% increase with the LID scenario.   Subwatershed Scale Build-Out   Urban sub basins had substantial runoff reductions using LID build-out scenarios and in one instance actually reduced beyond current conditions.    Conventional build-out had increases in runoff from 29-36% whereas LID build-out had a range of -2-7%.  This last finding is substantial illustrates that LID in a redevelopment scenario can serve to reduce runoff from current conditions.!Funding Funding is provided  by the Cooperative Institute for Coastal and Estuarine Environmental Technology (CICEET) whose mission is to support the scientific development of innovative technologies for understanding and reversing the impacts of coastal and estuarine contamination and degradation. Hydraulics Model – Cross Sections!23!Summary%of%Cross%SecMon%Data%Source%Source% Number%FEMA%FIS%Backup%Data% 111%%%%%%Duplicates% 19%Surveyed% 12%NHDOT/Consultants% 34%GIS% 44%Total( 220(•  FIS sections were duplicated as needed to provide immediate sections up and downstream of bridges!•  No backup data available for Lee!•  Projects included additional sections supplementing FIS sections!•  Improved modeling in RT108 corridor and tributaries!Hydraulics Model – Structural Data!24!Summary%of%Bridge%Structure%Source%for%the%Lamprey%River%Community% StaMon% Road%Name% Data%Source%Raymond% 181300% Dudley%Road%Electronic%WSP2%ﬁles%from%Roald%Haestad,%Inc.%March%1993%180964% Raymond%Road%(RT%27)%167900% Langford%Road%160746% Main%Street%155060% Epping%Street%154106% B&M%Railroad%147643% Freetown%Road%(RT%107)%141372% Presco`%Road%Epping% 136759% State%Route%101%127937% Epping%Road%(RT%27)% Electronic%HEC4RAS%ﬁles%from%NHDOT,%2010%123964% Blake%Road%As4built%drawings%from%NHDOT,%dates%vary%107459% Main%Street%(Plummer)%106269% Mill%Street%Electronic%HEC4RAS%ﬁles%from%NHDOT,%2000%105560% Calef%Hwy%(RT%125)%88171% Hedding%Road%(RT%87)% WSPRO%print%out%and%As4built%from%NHDOT,%2000%Lee% 61457% Wadleigh%Falls%Road%As4built%drawings%from%NHDOT,%dates%vary%35683% Lee%Hook%Road%Durham% 20082% Wiswall%Road% Electronic%HEC4RAS%ﬁles%from%CLD%ConsulMng,%2009%16028% Packer's%Falls%Road%FEMA%FIS%Backup%Data%Newmarket% 1602% RT%108%Summary%of%Bridge%Structure%Source%for%the%RT108%Corridor%Watercourse% StaMon% Road%Name% Data%Source%Floodplain% 71% Newmarket%Road%(RT%108)% Survey%drawings%from%NHDOT,%2010%Hamil%Brook% 1040% Newmarket%Road%(RT%108)%FEMA%FIS%Backup%Data%Longmarsh%Brook% 4182% Bedard%Road%Longmarsh%Brook% 1703% Longmarsh%Road%Longmarsh%Brook% 275% Tote%Road%Hydraulics Model – Dam and In-line Structural Data!25!Summary%of%In4line%Structure%Source%for%the%Lamprey%River%Community% StaMon% Road%Name% Data%Source%Epping% 127265% Bunker%Pond%Dam% Electronic%HEC4RAS%ﬁles%from%NHDOT%Lee% 61266% Wadleigh%Falls%Dam% Land%Records%Durham% 19859% Wiswall%Dam% Electronic%HEC4RAS%ﬁles%from%CLD%ConsulMng%Engineers%Newmarket% 1286% Coﬀee%Sluice%Electronic%HEC4RAS%ﬁles%from%Wright4Pierce%Newmarket% 1164% Macallen%Dam%•  NHDES Dam Management studying removal of Bunker Pond dam!•  Wiswall bridge has been replaced and downstream dam replacement in near future!•  Macallen Dam recently inspected per NHDES request !•  Spillway dimensions and layout, elevation field verified!• Calibration:!o  April 2007 – 7,590 cfs, Precipitation – 7.65 in!o  March 2010 – 6,550 cfs, Precipitation – 7.02 in!• Optimization parameters:!o  Manning’s ‘n’!o  Lag Time!o  Tc!• Simulated for !o  Time to peak!o  Runoff volume!o  Peak flow!Calibrating the Watershed 26 Calibrating the Watershed 27 Calibrating the Watershed 28!Hydrology Model – Calculated flood flow for the gaged 183 sq.mi. watershed !•  Results of calibrated model run for current land use (2005) using TP-40 rainfall. !Q100, TP-40 = 7,580 cfs  vs. Q100, FIS = 7,300 cfs !•  Results of calibrated model run for current land use (2005) using NRCC Atlas rainfall. !Q100, CA = 10,649 cfs!•  68-percent confidence interval of gaging station estimate for data from 1935-2009, !Q100, LP3 = 9,411 cfs!!L0.01,0.68 = 8,862 cfs     H0.01,0.68  = 10,040 cfs!29!Calibrating the Watershed 

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Climate and Land Use Consequences to 100-Year Flooding

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