US Army Corps of Engineers Hydrologic Engineering Center
Design of Flood Control Improvements by System Analysis: A Case Study October 1971 Approved for Public Release. Distribution Unlimited. TP-51
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4. TITLE AND SUBTITLE Design of Flood Control Improvements by Systems Analysis: A Case Study
5c. PROGRAM ELEMENT NUMBER
5d. PROJECT NUMBER 5e. TASK NUMBER
6. AUTHOR(S) Howard O. Reese, Arnold V. Robbins, John Jordan, Howard V. Doyal
5F. WORK UNIT NUMBER
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) US Army Corps of Engineers Institute for Water Resources Hydrologic Engineering Center (HEC) 609 Second Street Davis, CA 95616-4687
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12. DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES Presented at the ASCE National Meeting on Environmental Engineering, October 1971. 14. ABSTRACT A hydrologic-economic simulation model was developed to evaluate alternative protection schemes in the design of an authorized federal flood control project for 125 miles of the Tibbee River floodplain in Mississippi. The model requires input consisting of unit hydrographs, streamflow routing coefficients and storage functions, a pattern storm, rainfall loss rate functions, and flow-damage-frequency relations. A single synthetic pattern storm was used in conjunction with flow-frequency curves at index locations to generate a series of floods for comparing alternative protection schemes with existing conditions. The effect of channel improvements on flood runoff characteristics was evaluated by using storage routing functions that account for change in storage-discharge relations. Based on results obtained from using the model, a channel improvement plan was tentatively selected for the Tibbee River basin from the alternative schemes evaluated. 15. SUBJECT TERMS flood control, systems analysis, Mississippi, model studies, flood damage, hydrologic aspect, economics, mathematical models, design, analytical techniques, methodology, channel improvement, flood protection, stream improvement, Tibbee River, case study 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON a. REPORT U
b. ABSTRACT U
c. THIS PAGE U
17. LIMITATION OF ABSTRACT UU
18. NUMBER OF PAGES 30 19b. TELEPHONE NUMBER
Design of Flood Control Improvements by Systems Analysis: A Case Study
October 1971 US Army Corps of Engineers Institute for Water Resources Hydrologic Engineering Center 609 Second Street Davis, CA 95616 (530) 756-1104 (530) 756-8250 FAX www.hec.usace.army.mil TP-51
Papers in this series have resulted from technical activities of the Hydrologic Engineering Center. Versions of some of these have been published in technical journals or in conference proceedings. The purpose of this series is to make the information available for use in the Center's training program and for distribution with the Corps of Engineers. The findings in this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products.
DESHW OF n O O D GOMTROL IHWOBrlEmNTS BY SYSTEMS M L Y S I S : A CSE s ~ F ~ " J ( ~ )
bps
( 4 ) Howard 0. ease!" Arnold V. ~ o b b i n s !3' John 8. Jordan,
and' Harold V, ~ o ~ a l ( ~ )
A hydrologic-economic simuBae9~n m d e l was developed tto evaluate alter-
na t ive protec t ion schemes i n the design of an authorized fede ra l f lood
contro l p ro jec t f o r 125 m i l e s of the Tibbee River f lood p l a i n i n M s s i s s i p p i .
The model requi res input cons is t ing of u n i t hydrographs, s t r e m f l o w rout ing
c o e f f i c i e n t s and s to rage functions, a p a t t e r n storm, r a i n f a l l l o s s r a t e
functions, and Plow-damge-frequency r e l a t i o n s . A s i n g l e syn the t i c pa t t e rn
storm was used i n conjunction with flow-frequency curves a t index loca t ions
t o generate a series of f loods f o r comparing a l t e r n a t i v e protec t ion schemes
with e x i s t i n g condit ions. The e f f e c t of channel improvements on flood
runoff c h a r a c t e r i s t i c s was evaluated by using s torage routing functions
t h a t account f o r changes i n storage-discharge r e l a t i o n s , Based on r e s u l t s
obtained from using the model, a channel. i q r o v e e w e plan was t e n t a t i v e l y
se lec ted f o r the Tibbee River basin from the al tematiave schems evaluated.
( I ) For presenta t ion a t the ASCE National Meeting on Environmental Engineering, October 1971.
(2 ) Chief, Special Assistance Branch, The Hydrologic Engineering Center, U. S. A m y Corps of Engineers, Davis, Ca l i fo rn ia ,
(3) Civi l Engfneer, P ro jec t Development Seceioa, Nobile D i s t r i c t , U. S. Army Corps of Engineers, Mobile, Alabama.
' 4 ) Chief, Hydrology Sect ion , Mobile D i s t r i c t , U. S. Amy Corps of Engi neers , Mobile, ABabam,
'5) C iv i l Engineer Technician, Hydraulic Data Section, Mobile D i s t r i c t , U . S. Army Corps of EngBneers, Mobile, ABabam.
A federal project involving extensive stream clearing,
straightening and enlargement was authorized by Congress in 1958.
The purpose of the project is to achieve flood control and drainage
on 466 miles of flood plain along 22 tributary streams of the upper
Tombigbee River in Mississippi and Alabama. A current study conducted
on a cooperative basis by the Mobile District and The Hydrologic
Engineering Center, Corps of Engineers, is concerned with a portion
of the overall project, namely 125 miles of f.l.ood control improvements
authorized for a system of 1.0 streams in the Tlbbee River basin,
Mississippi (figure 1). The objectives of the study are to determine
the effect of alternative channel improvement schemes on flood runoff
characteristics in the stream system, to determine the reductions in
flood damage associated with the alternative plans, and to select
from among the alternatives the plan that would most economically
achieve the fl..ood control ob jecti.ves . The methodology adopted for the study required the development
of a generalized hydrologic-economic ma$hematical model to simulate the
flood runoff characteristics of the basin under existing conditions and
for alternative improvement schemes, including detention structures
that are planned by the U. S. Soil Conservation Service. This paper
describes the simulation model and study procedures and presents some
of the results of the study.
The total , area of %he Tibbee River basin is
1,121 square miles, of which about U O s q w e miles are i n the flood
p la in of %he 10 s taems authorized for improvement. The basin has
a maximum width of 30 miles, an average width or" 2 l m i l e s , and a
stream length of 74 miles (from the mouth of Tibbec River to the head
of Sakatonchee Creek, %ts longest t r i b u t a q ) . '$ke t e r r a in is f a i r l y
rugged with rather high r e l i e f varying from elevgution la Lo 400 f ee t ,
rn.s.1.
The Tibbee River i s fomed a t the junction of Line and Sakatonchee
Creeks and it flows easter ly about 24 mil-es to join the Tonabjigbee River
through the r ight bank about 35 miles northwest of Colmbus, Mississippi.
It has an average gradient of 1.5 f ee t per mile. Its %ributaPies
range i n length from about 5 miles t o 50 miles with gradients generally
steeper than tha t of' the main stem. The fl,ood plain along the Tibbee
River and i ts tribuLaP.ies awrages about E mile In width and i s subject
t o frequent flooding,
The basin area i s located within the Tombigbee H i U s and Black
Prair ie d i s t r i c t s of the Gulf Coastal Halain physiowaplaic province.
The downstream 4 on. 5 miles of the Ti.bbee River traverses the Tombigbee
H i l l s d i s t r i c t with topography rangiwg from 9 . 0 ~ ~ smoothly rounded
hi l . ls t o h i l l s and ridges separated by nwrow valleys. The upstrem
reach of the Tibbee River and i t s t r ibu ta r i e s i s located i n the Black
Pra i r i e d i s t r i c t where the topography var ies from nearly f l a t
t o smoothly rounded h i l l s or Low r e l i e f .
Climatology. The Tibbee River basin has a temperature climate
with warm sumners and m i l d winters. The normal annual temperature
is 64 degrees with monthly normals ranging from 47 degrees i n
January t o 81 degrees i n July. '1111e minimu? recorded temperature
i s -10 degrees and the maximum is 113 degrees. The frost- f ree
period normally l a s t s from April t o November.
Precipi ta t ion during the year is abundant and f a i r l y well
d is t r lbuted. The normal annual. r a i n f a l l i s almost 49 inches, of
which 58 percent f a l l s i n the winter and spring, 24 percent in the
summer, and 18 percent in the f a l l . The average annual snowfall is
about 35 inches.
Flood producing storms may occur a t any time but a r e more
frequent during the winter and spring. Such storms a r e usualQ of t he
f ron ta l type covering large meas and l a s t i ng from 2 t o 4 days. S m e r
storms a re generally of the thunderstorm type with high in tens i ty
over small. areas. Recorded rainfall .1~ i l l the basin include maximums of
3.20 inches i n a 1-hour period, 6.53 inches i n 1.2 hours, and 7.43
inches i n 24 hours. The 1- and 12-hour maximums occurred during a
storm on June 1-2, 1947, and the 24-how maximum occurred i n
January 1950.
Land Use. About half of the t o t a l basin area i s i n farms. Sixty
percent of .the farmland acreage i s about equblly divided between
cropland and other uses such a s house l o t s , roads, pastures andl
wasteland. The remaining 40 percent is woodland. More than
80,000 acres a r e i n t h e flood pla in along the 10 project streams.
It is estimated t h a t 30 percent of %his flood p la in land is i n
cul t ivat ion, 15 percent i s i n pastme o r id le , and 55 percent i s wood-
land. It i s estimated t h a t flood amages t o flood p la in development;
average $1.,837,000 a yew, consist ing mainw of agricul.tural. losses.
The improvement of t he project streams would reduce these flood
damages and permit more intensive agr icu l tu ra l use of t h e flood
plains.
INVEST IGAT TON
General. To accomplish the study objectives, it was concluded
t h a t a systems analysis of various a l te rna t ive schemes of basin develop-
ment f o r the Tibbee River was required, and t h a t a hydrologic-economic
simulation model should be developed t o f a c i l i t a t e the analysis . It was
recognized t h a t extensive channel improvement works i n a r i ve r system
could cause an adverse peaking e f f e c t on runoff; i.e., peak r tnoff r a t e s
could l i ke ly be la rger because of t he more rapid concen%ration of runoff
resu l t ing from more e f f i c i e n t conveyance. Therefore, %he model was
developed primari1.y for the purpose of epretl.uating t he e f fec t s of
a l t e rna t ive channel improvement plans on the flood runoff charac te r i s t i cs
of timing and magnitude of peak runoff ra te . Another major purpose o f the
model was t o determine the reductions i n flood damage fo r the a l te rna t ive
plans. A general.ized computer program (ra infa l l - runoff model)
developed by The Hydrologic Engineering Center was used f o r
mode1:ing purposes.
The appl ica t ion o f the general ized simulat ion model required
t h e devel.opment of c e r t a i n hydrologleal and economic inputs, such as
(1) u n i t hydrograph and l o s s rate c r i t e r i a , (2) channel rout ing c r i t e r i a ,
(3) s y n t l ~ e t i c pa t t e rn storm, (4) d i jcharge-frequency and stage-discharge
r e l a t i o n s , and ( 5 ) stage-damage r e l a t i o n s .
Economic Studies. The procedure used f o r determining reductions
i n f lood damage a t t r i b u t a b l e Lo chanael improvement works was t o
compute the d i f ference i n average annual flood damages1 between
e x i s t i n g conditions and improved conditions. Average annual f lood
damages f o r e x i s t i n g condit ions were computed from known o r derived
stage-discharge, discharge-frequency, and stage-damage re la t ionships .
For 'mproved conditions, average annual f lood damages are usually computed
from these same rel.a-kionships with t h e stage-discharge re la t ionsh ip modified
t o r e f l e c t t h e changes i n stage. However, f o r t h i s study i t was a l s o
necessary t o modify t h e discharge-frequency re la t ionsh ip t o r e f l e c t t h e
magnitude of the peaking e f f e c t on runoff resul . t ing from upstream channel
improvement works. The need f o r modifying t h i s r e la t ionsh ip made the
determination of flood damage reduction more d i f f i c u l t .
I n formulating the optimal plan of channel. improvement works f o r
t h e Tibbee River basin, es t imates of f lood damage reduction a t t r ibutable
' ~ v e r a ~ e annual f lood damage i s defined as t h e expected value of annual flood damage computed by in tegra t ing t h e damage-exceedence frequency function.
6
Co each alternative plan evaluated were determined. For this
determination, the flood plains of the Tibbee River and its
tributaries were subdivided into 21 plannirng reaches vanyi.ng in length
from 2 to 17 miles (figure 1). Based on detaiLed economic studies,
flood damages were deteMned for each planni~lg reach and related
to stage at the index station (representatiw reference point)
selected for the reach. Using stage-discharge and discharge-frequency
relationships, average annual. flood damages were computed at each
index station for existing conditions and for each alternative plan
as described later in the paper.
Hydrologic and IQnirau3.i~ Studies. A discharge-frequency
statistical analysis was made from stremflow data for gaging stations
located on the Tibbee River and its tributaries and on adjacent streams
of similar size and comparable hydrologic characteristics. A relationship
of drainage area versus the annual mean was devel.oped, A skew coefficient
of zero and a standard deviation of 0.24 were adopted and used with this
relationship for determining the discharge-frequency relationship at
each index station for existing conditions in the basin.
Extensive backwater computations for existing conditions and for
alternative plans of improvement were made to determine stage-discharge
relations at each index station, pertinent water surface profiles, and
storage-outflow relations for the selected channel routing reaches. Data
on surveyed cross-sections and topographic maps were available. The
roughness coeff ic ients used i n Manningqs f0muZ.a were based on
known high water marks and r a t i ng s ta t ions i n t he basin.
FOP study purposes, the Tibbee River basin was subdivided in to
216 subareas. Synthetic uni t hydrographs were derived fo r each
subarea by the Clark un i t hydrograph method using generalized
coeff ic ients . Unit hydrograph and r a i n f a l l loss r a t e coefficients
were derived for 22 stream gaging l x a t i o n s i n the Tibbee River basin
and other adjacent stream basins from an analysis of streanflow and
r a i n f a l l data f o r a t o t a l of 89 runoff events (2 t o 8 per location).
The r e su l t s of t h i s analysis were used for developing generalized
coeff ic ients for application t o ungaged locations.
The methodology adopted fo r evaluating the e f f ec t of channel
improvements on flood runoff character is t ics required the development
of a single representati.ve synthetjc pat tern storm for the Tibbee River
basin. It a l so provided for computing a synthetic pattern flood for
each submea from the pattern storm and, using mu.l.tiples of the
pat tern flood, for determining other floods of pertinent magnitudes or
frequencies.
A uniform a rea l d i s t r ibu t ion of rainfall . was used f o r computing
the pattern storm. In t h i s way, each portion of the basin had a
representative e f f ec t on flood dalerminations. Although a single pat tern
storm may not be to ta l ly representative fo r the en t i r e Tibbee River
basin as well a s the headwater areas, it would have been extremely
d i f f i c u l t and laborious t o attempt many representative storm centerings
within the basin. Also, it is doubtful t h a t r e s u l t s would have
been s u b s t a n t i a l l y d i f f e r e n t than those obtained from a s ing le
uniform storm pa t t e rn . While t h e e f f e c t s of t r i b u t a r y runoff would
actual.1.y va-y, depending on storm centering, the ne t e f f e c t of all
centerings and a11 storm magnitudes would probably not be s u b s t a n t i a l l y
d i f f e r e n t from t h a t computed using a uniform d i s t r i b u t i o n .
The area-depth-duration r e l a t i o n adopted fo r t h e pa t t e rn storm
was of p a r t i c u l a r importance because the r e s u l t i n g pa t t e rn fl.oods
were t o be representa t ive of h i s t o r i c a l f loods. 1% was determined
t h a t i f t h e peak-to volume re la t ionsh ips of t h e pa t t e rn floods a r e
representa t ive of h i s t o r i c a l f loods throughout the basin, then o the r
f loods derived a s mul.tiples o f t h e pa t t e rn f loods would be equally
r ep resen ta t ive because peak-to-volume r a t i o s of h i s t o r i c a l f loods a r e
r e l a t i v e l y independent of flood magnitude. The adopted c r i t e r i a f o r the
storm were a r a i n f a l l i n t e n s i t y of 5-year recurrence in te rva l , 8. r a i n -
fa1.l dure t ion o f 48 hours, and an a r e a s i z e of 200 square miles. Based
on r a i n f a l l da ta i n Weather Bwreau Technical Papers 40 and 49, it was
determined t h a t the t o t a l s t o m r a i n f a l l was 5.7 inches.
For t h i s study, the pa t t e rn f lood a t any loca t ion i n t h e bas in i s
defined a s the runoff from t h e pa t t e rn storm. Tke pa t t e rn flood
hydrograph f o r each subarea was computed by applying t h e pa t t e rn storm
r a i n f a l l excess t o t h e syn the t i c u n i t hydrograph. The pa t t e rn flood
hydrographs f o r the o ther locat ions i n the bas in were determined by
rout ing and combining these subarea pa t t e rn flood hydrographs. The
Muskingum rou t ing method was used f o r t h e smaller streams i n the head-
water a reas and the nonlinear s torage rout ing method (modified ~ u l s )
was used f o r the o t h e r stream reaches. The l a t t e r method required t h e
development of storage-outflow r e l a t i o n s Tor each sel.ected channel
rou t ing reach f o r e x i s t i n g and improved condit ions. I n t h i s r e l a t i o n ,
t h e s torage value is t h e volume of water i n t h e channel and overbank
wi th in the rout ing reach corresponding t o a given steady s t a t e water
surface p r o f i l e . The storage-.outflow r e l a t i o n f o r e x i s t i n g condit ions
was adjusted t o r e f l e c t the changes i n s torage f o r each plan of
channel improvement considered. Therefore, although t h e same pa t t e rn
storm was used, t h e r e s u l t i n g pa t t e rn f loods a t a given loca t ion were
d i f f e r e n t f o r each a l t e r n r t i v e plan as i l l u s t r a t e d i n f i g u r e 2 fo r
one of t h e index s t a t i o n s on Catalpa Creek.
A s e r i e s o r s e t o f nine syn the t i c flood hydrographs a t a l l
l oca t ions i n t h e bas in was developed f o r e x i s t i n g condit ions and f o r
each considered plan o f improvement. The s e t of f lood hydrographs was
synthesized by mult iplying al.1 of t h e subarea p a t t e r n f lood hydrograph
ordinates by nine predetermined r a t i o s and by rou t ing and combining
the s u b ~ r e a pa t t e rn f loods computed f o r each mult iple. Tlie same
mult iples used f o r e x i s t i n g condit ions were used f o r each plan of
improvement. Multiples were se lec ted t o produce f lood magnitudes
corresponding t o a frequency range from four t o twelve times per year
(zero flood damage s t age ) t o approximately once i n 200 years.
Using discharge-frequency curves, an exceedence p robab i l i ty was
assigned t o each mult iple flood a t each index s t a t i o n locat ion f o r
e x i s t i n g conditions. For each plan of improvement, the exceedenee
probabi l i ty f o r each mul.tiple flood was assumed t o be the same a s t h a t
es tabl i shed f o r e x i s t i n g conditfons, The p r o b a b i l i t i e s associa ted
with each mul.tip1.e were used, i n conjui~cQion with flow-damage c w v e s ,
t o compute average annual flood damages a t each index s t a t i o n f o r
e x i s t i n g condit ions and f o r each plan of improvement. The assigned
range of p robab i l i ty of each mult iple f lood is mul t ip l ied by the
damage caused by t h a t f lood, and the sum of these cross products f o r
a l l of the nine mul t ip le f loods is the average annual damage f o r the
given condit ion.
RESULTS
Some of t h e r e s u l t s of t h e inves t iga t ion a r e i l . l u s t r a t ed on
f igures 2 through 6 f o r two of the planning reaches analyzed. The
resul - t s f o r these two loca t ions a r e representa t ive of t h e o the r
Locations i n the basin.
Examples of computed flow-probability-damage re l .a t ions and average
annual flood damages f o r e x i s t i n g conditons and various a l t e r n a t i v e
plans of basi n development a r e shown on f igures 3 and 5. The flood
damage reduction a t t r i b u t a b l e t o the a.l . le~'native plans is a l s o shown
on these f igures . For the a l t e r n a t i v e plan providing f o r channel
improvements on a l l 10 streams i n the Tibbee River bas in , t h e increase
i n the peak flow r a t e of the pa t t e rn f lood (f lood 6 on f igure 5)
a t r i v e r mi1.e 17.7 on t h e Tibbee River would be 35 percent. However,
because of changes i n the stage-d ischarge r e l a t i o n , f lood damage
reduction i n t h e planning reach would decrease 62 percent. Shown on
f igure 6 i s a comparison o f stage-frequency r e l a t i o n s a t t h i s
loca t ion f o r e x i s t i n g conditions, channel improvements on a l l 10
streams, and channel. improvements on Tibbee River only. The d i f ference
between the two r e l a t i o n s f o r improved condit ions i s due t o the peaking
e f f e c t catused by upstream channel improvements.
The e f f e c t s of vari.ous upstream a l t e r n a t i v e plans of bas in develop-
ment on the runoff c h a r a c t e r i s t i c s of t iming and magnitude o f peak flow
r a t e a r e i l l u s t r a t e d by t h e p a t t e r n f lood hydrographs shown on f i g u r e s
2 and 4 and the f low-probabil i ty da ta tabula ted on f i g u r e s 3 and 5.
The r e s u l t s of t h e inves t iga t ion a t a l l index s t a t i o n locat ions show t h e
following general t r ends on increases i n peak flow rates from upstream
channel improvements:
(1) Peak fl.ow r a t e s increase a s t h e percentage of stream length
improved inc reases , a s would be expected.
(2) For given length of stream t o be improved, peak flow rates
increase a s t h e degree o f p ro tec t ion (deslgn capaci ty of improved
channel) increases . This e f f e c t is I l l u s t r a t e d by t h e pa t t e rn f lood
hydrographs shown on f i g u r e 2 f o r e x i s t i n g condit ions and four a l t e r n a t i v e
plans .
(3) For given improved condit ions, t h e increase i n peak flow rates
decreases percentagewise with increases i n f lood magnitude.
12
CONCLUSTORS
The most important concept of t h e inves t iga t ion m s t h e
determination o f the runoff peaking e f f e c t of channel improvement
works based on changes i n the storage-outflow r e l a t i o n of t h e f lood
p l a i n and streams. Another important rand unique concept was t h e
computation of syn the t i c f lood hydrographs at nmerous l .ocations a s
multip1.e~ of p a t t e r n f loods derived from one s i n g l e representative
syn the t i c pa t t e rn s t o m f o r a stream system.
Upstream channel improvement works fo r f lood control would tend t o
increase t h e magnitude of peak flow r a t e s now experienced on t h e Tibbee
River main stem. !hey would a l s o tend t o increase t h e average annual
flood damages on the main stem unless it was enlarged t o accommodate t h e
increased discharges. The magnitude of these e f f e c t s was assessed with a
reasonable mount of computation using a s implif ied hydrologic-economic
simulat ion model of t h e basin, along with c e r t a i n necessary assumptions
and genera l iza t ions .
The procedure described here in f o r the evaluat ion ?f flood con5rol
channels i n r u r a l a reas could a l s o be appl ied t o the study of urban flood
problems. The genera l iza t ions would, of course, he t a i l o r e d t o the
s p e c i f i c a rea of s tudy, but the methodology and eomputalional procedure
would be the sme. Future s t u d i e s should inves t iga te the p o s s i b i l i t y of
adding t o the model an optimizat ion rout ine t o provide f o r t h e s e l e c t i o n
of p ro jec t s involving a combination of two o r more s t r u c t u r a l measures
(denteartion s t r u c t u r e s together with levees or cha.lnels, e t c . ) which a r e
t o achieve a given objec t ive (protec t ion aga ins t a spec i f i ed f lood) .
13
Many persons i n t h e Mobile D i s t r i c t Corps of Engineers o f f i c e
have been involved i n t h i s study. Mr. Leo R. Beard, Direc tor of
The Hydrologic Engineering Center, who developed the simulat ion
model, described here in , has given h i s support and suggestions f o r
i t s use i n t h i s study. Mr. Herbert W. Hereth and Mrs. Marilyn Hulst
of the HEC s t a f f , and M r . Lewis G. Hulman, formerly o f the HEC staff
and now of t h e Atomic Energy Commission, furnished valuable
a s s i s t ance .
REFERENCES
1. The Hydrologic Engineering Center, General ized Computer Program, "HEC-1 Flood Wydrograph Package," Corps of Engineers, October 1970.
2. Clark, C . O . , 9qStorage and t h e Unit Hydrograph," Trans. ASCE, 1945.
$9 miles
TPBBEE RIVER 3ASlX (1,121 sq. m i ) ..--
FIGURE 1
gamz: %$tern ~ ~ o o d ie ~ ~ o o d 6) A L ~ " W ~ T ~ =RAN
- - E X P S T m C O m n Z O N S - . -- Clear md Q m g
-- -
_- _EL QQQ DAflAGE 5 --!?PUT FLOOD O A ~ G E S FOR S ~ A T I O F J NO. FkON PRO8 .-.- ~&--- ~-I=-sv~--. . PRO6 - - - S UfQ .
- 1 2272. .go4 -00 Z 2625. 1 .270 2 _ 3 ~ 1 0 , 10270 .01
4.26 3 3761. 18067---- ----- 3 4153. 1 .067 I . 45 4 5146. 6827 4.77 4 5 5 6 6 , .82'7 3. 17 -.-.-- - -- - - 5 . 6861, _ - 2 s A-QL S 7292. - 4 6 5 2.72 6 9608. .338 3924 S l , .... l - - -__&Z--. 7 _ 1394.7. -- .16Z .- --- 2.09 - 7 14114. .I62 I .8%. 8 1 9 5 5 6 . . 8 6 l l . O Z - . @ 19621. _ _ - .Obi . 9.1
.--.--.- % --.-. 22.Ia25 5- - - Z Q Z ~ -----..--...--- A, 9 27266 . .029 * 46
h. ------ - DAMAGE REDUCTION 8.89
FLOOD D A W G E S f OR STAT18~ - -- -- - -- NO, FLOd PRO8 $i uN-
A m 25 Foot CBPamel
- - - -- - - - - - - - - - - - . - FL.000 DAMAGES FOR STATIOW
__iYQ3LELe)w P R O L X Y ! ! 1 24-34. *804 *60
_,_Z_-- 3g%s* 1 * 270 -----dm-- 5432. 1.067 * OO
- 1229 Q 27 -- .a0 5 8822 . .465 0 0 0
- -- - - - - - -- - - - .- .- -- - -- - - - -- - A v G ANN DMC _ - . 2, as- _ PVG AMM DDMG 1-78
-. -- - 19.61 - D A M E REQ-UCTXQM ----.-.-- ---- . DAMAGE E D - U C f f PM ?o.si
FLOOD DAMAGES FOR ~7"@Tf&?&-- - -- No. FLOW P R O 6 $019
--.L ZBL._ -,B&- ,ao 2 e 1,270 * 00 3 -.-. ------ . QO L - ~ ~ Q Q ? --.---
4 ,827 - 0 0 5 9705, *A@!! 00-._ CATATJIPA K 6 12456. .330 . D O R.M. 6.36 7 15738, @ \ 6 i ? *21 B 2 0 9 8 6 - sOBl *38
. . * 33 --
AVG ANN DUG - *7+--=_
AND DETENTION S
TIBBEE RIVER R.M. 17.70
D.A. = 928 Sq. Mi.
FLOW-PR(?XA 9SI'T~ITY-r)~WGE RELATTONS 'III.BBEE RTVER R.M. 17.70
EXISTING CONIITTIONS DEZ'ENTION STRUCTURES
Feuoo DAMAGES F O R STATION NO. FLOW P R O 0 S UH I 6449 3.269 I6aRIS 2 9712 1 ,237 2 0 9 9 1 3 1 4 6 6 3 ,896 23.27 4 2 0 5 5 4 6645 22e87 5 28948 0455 219 73 6 42723 9304 18.43 7 62043 0134 9 9 7 1 8 90665 ,048 4939 9 133410 , 022 2e56
AVG ANN DYG 140 9 7 6
FLOOD DAMAGES FCIR S T A T I O N NO. FLOW P R ~ H SUM P 5786 3,269 IL'3ol.3 2 8802 1 9 2 3 7 1 8 e 4 8 3 12989 ,896 2 0 e 9 2 4-- 11963 .a645 20 s 3.3, 5 24925 0455 P9e 3 9 6 35973 9304 16. 72 7 52'740 ,134 8 9 93 8 7 6 5 7 2 ,048 3.94 9 PI3200 9022 2 - 2 9
BVG ANN DYG 123e90
DAMAGE REDUCTION 16987
WOTE: Pattern Fl.ood is Flood 6
CHANNEL IMPROVEr.IENTS
FLOOD DAMAGES FOR NO9 FLOW P R O 0 P 1 5 0 2 9 3,269 2 2 0 4 4 8 1 ,233 3 2 7 2 2 1 .896 4 34666 ,646 5 44442 9455 6 5 7 6 6 6 9304 7 7 7 0 6 2 .134 8 1 0 6 1 8 9 e048 9 149526 9022
STATInN SUM
0 9
1 9 5 3 5921
1 1 - 6 5 120 40 11 *39
6.66 3.34 2 9 06
AVG ANN OYG 5 4 e 2 3 .,
CHANNEL IMPROVEMENTS A M ) DETENTION STRUCTURES
FLOOD DAMAGES FOR NO, FLOW PRO9
1 13767 3,269 2 P S O 4 6 f 923 7 3 25614 ,896 4 32242 ,646 5 40671 9455 6 52450 a304 I 8 8 2 7 4 ah34 8 9 2 3 4 7 a048 9 1 2 9 2 7 3 ,022
STATION SUM
0 9
965 3 e 4 4 8,99
PfeOO p0a25
5993 2- 88 1080
A V G ANN DYG 44.93
DAMAGE HEOUCTPON 86e54 DAMAGE REDUCTION 9SaR3
Technical Paper Series TP-1 Use of Interrelated Records to Simulate Streamflow TP-2 Optimization Techniques for Hydrologic
Engineering TP-3 Methods of Determination of Safe Yield and
Compensation Water from Storage Reservoirs TP-4 Functional Evaluation of a Water Resources System TP-5 Streamflow Synthesis for Ungaged Rivers TP-6 Simulation of Daily Streamflow TP-7 Pilot Study for Storage Requirements for Low Flow
Augmentation TP-8 Worth of Streamflow Data for Project Design - A
Pilot Study TP-9 Economic Evaluation of Reservoir System
Accomplishments TP-10 Hydrologic Simulation in Water-Yield Analysis TP-11 Survey of Programs for Water Surface Profiles TP-12 Hypothetical Flood Computation for a Stream
System TP-13 Maximum Utilization of Scarce Data in Hydrologic
Design TP-14 Techniques for Evaluating Long-Tem Reservoir
Yields TP-15 Hydrostatistics - Principles of Application TP-16 A Hydrologic Water Resource System Modeling
Techniques TP-17 Hydrologic Engineering Techniques for Regional
Water Resources Planning TP-18 Estimating Monthly Streamflows Within a Region TP-19 Suspended Sediment Discharge in Streams TP-20 Computer Determination of Flow Through Bridges TP-21 An Approach to Reservoir Temperature Analysis TP-22 A Finite Difference Methods of Analyzing Liquid
Flow in Variably Saturated Porous Media TP-23 Uses of Simulation in River Basin Planning TP-24 Hydroelectric Power Analysis in Reservoir Systems TP-25 Status of Water Resource System Analysis TP-26 System Relationships for Panama Canal Water
Supply TP-27 System Analysis of the Panama Canal Water
Supply TP-28 Digital Simulation of an Existing Water Resources
System TP-29 Computer Application in Continuing Education TP-30 Drought Severity and Water Supply Dependability TP-31 Development of System Operation Rules for an
Existing System by Simulation TP-32 Alternative Approaches to Water Resources System
Simulation TP-33 System Simulation of Integrated Use of
Hydroelectric and Thermal Power Generation TP-34 Optimizing flood Control Allocation for a
Multipurpose Reservoir TP-35 Computer Models for Rainfall-Runoff and River
Hydraulic Analysis TP-36 Evaluation of Drought Effects at Lake Atitlan TP-37 Downstream Effects of the Levee Overtopping at
Wilkes-Barre, PA, During Tropical Storm Agnes TP-38 Water Quality Evaluation of Aquatic Systems
TP-39 A Method for Analyzing Effects of Dam Failures in Design Studies
TP-40 Storm Drainage and Urban Region Flood Control Planning
TP-41 HEC-5C, A Simulation Model for System Formulation and Evaluation
TP-42 Optimal Sizing of Urban Flood Control Systems TP-43 Hydrologic and Economic Simulation of Flood
Control Aspects of Water Resources Systems TP-44 Sizing Flood Control Reservoir Systems by System
Analysis TP-45 Techniques for Real-Time Operation of Flood
Control Reservoirs in the Merrimack River Basin TP-46 Spatial Data Analysis of Nonstructural Measures TP-47 Comprehensive Flood Plain Studies Using Spatial
Data Management Techniques TP-48 Direct Runoff Hydrograph Parameters Versus
Urbanization TP-49 Experience of HEC in Disseminating Information
on Hydrological Models TP-50 Effects of Dam Removal: An Approach to
Sedimentation TP-51 Design of Flood Control Improvements by Systems
Analysis: A Case Study TP-52 Potential Use of Digital Computer Ground Water
Models TP-53 Development of Generalized Free Surface Flow
Models Using Finite Element Techniques TP-54 Adjustment of Peak Discharge Rates for
Urbanization TP-55 The Development and Servicing of Spatial Data
Management Techniques in the Corps of Engineers TP-56 Experiences of the Hydrologic Engineering Center
in Maintaining Widely Used Hydrologic and Water Resource Computer Models
TP-57 Flood Damage Assessments Using Spatial Data Management Techniques
TP-58 A Model for Evaluating Runoff-Quality in Metropolitan Master Planning
TP-59 Testing of Several Runoff Models on an Urban Watershed
TP-60 Operational Simulation of a Reservoir System with Pumped Storage
TP-61 Technical Factors in Small Hydropower Planning TP-62 Flood Hydrograph and Peak Flow Frequency
Analysis TP-63 HEC Contribution to Reservoir System Operation TP-64 Determining Peak-Discharge Frequencies in an
Urbanizing Watershed: A Case Study TP-65 Feasibility Analysis in Small Hydropower Planning TP-66 Reservoir Storage Determination by Computer
Simulation of Flood Control and Conservation Systems
TP-67 Hydrologic Land Use Classification Using LANDSAT
TP-68 Interactive Nonstructural Flood-Control Planning TP-69 Critical Water Surface by Minimum Specific
Energy Using the Parabolic Method
TP-70 Corps of Engineers Experience with Automatic Calibration of a Precipitation-Runoff Model
TP-71 Determination of Land Use from Satellite Imagery for Input to Hydrologic Models
TP-72 Application of the Finite Element Method to Vertically Stratified Hydrodynamic Flow and Water Quality
TP-73 Flood Mitigation Planning Using HEC-SAM TP-74 Hydrographs by Single Linear Reservoir Model TP-75 HEC Activities in Reservoir Analysis TP-76 Institutional Support of Water Resource Models TP-77 Investigation of Soil Conservation Service Urban
Hydrology Techniques TP-78 Potential for Increasing the Output of Existing
Hydroelectric Plants TP-79 Potential Energy and Capacity Gains from Flood
Control Storage Reallocation at Existing U.S. Hydropower Reservoirs
TP-80 Use of Non-Sequential Techniques in the Analysis of Power Potential at Storage Projects
TP-81 Data Management Systems of Water Resources Planning
TP-82 The New HEC-1 Flood Hydrograph Package TP-83 River and Reservoir Systems Water Quality
Modeling Capability TP-84 Generalized Real-Time Flood Control System
Model TP-85 Operation Policy Analysis: Sam Rayburn
Reservoir TP-86 Training the Practitioner: The Hydrologic
Engineering Center Program TP-87 Documentation Needs for Water Resources Models TP-88 Reservoir System Regulation for Water Quality
Control TP-89 A Software System to Aid in Making Real-Time
Water Control Decisions TP-90 Calibration, Verification and Application of a Two-
Dimensional Flow Model TP-91 HEC Software Development and Support TP-92 Hydrologic Engineering Center Planning Models TP-93 Flood Routing Through a Flat, Complex Flood
Plain Using a One-Dimensional Unsteady Flow Computer Program
TP-94 Dredged-Material Disposal Management Model TP-95 Infiltration and Soil Moisture Redistribution in
HEC-1 TP-96 The Hydrologic Engineering Center Experience in
Nonstructural Planning TP-97 Prediction of the Effects of a Flood Control Project
on a Meandering Stream TP-98 Evolution in Computer Programs Causes Evolution
in Training Needs: The Hydrologic Engineering Center Experience
TP-99 Reservoir System Analysis for Water Quality TP-100 Probable Maximum Flood Estimation - Eastern
United States TP-101 Use of Computer Program HEC-5 for Water Supply
Analysis TP-102 Role of Calibration in the Application of HEC-6 TP-103 Engineering and Economic Considerations in
Formulating TP-104 Modeling Water Resources Systems for Water
Quality
TP-105 Use of a Two-Dimensional Flow Model to Quantify Aquatic Habitat
TP-106 Flood-Runoff Forecasting with HEC-1F TP-107 Dredged-Material Disposal System Capacity
Expansion TP-108 Role of Small Computers in Two-Dimensional
Flow Modeling TP-109 One-Dimensional Model for Mud Flows TP-110 Subdivision Froude Number TP-111 HEC-5Q: System Water Quality Modeling TP-112 New Developments in HEC Programs for Flood
Control TP-113 Modeling and Managing Water Resource Systems
for Water Quality TP-114 Accuracy of Computer Water Surface Profiles -
Executive Summary TP-115 Application of Spatial-Data Management
Techniques in Corps Planning TP-116 The HEC's Activities in Watershed Modeling TP-117 HEC-1 and HEC-2 Applications on the
Microcomputer TP-118 Real-Time Snow Simulation Model for the
Monongahela River Basin TP-119 Multi-Purpose, Multi-Reservoir Simulation on a PC TP-120 Technology Transfer of Corps' Hydrologic Models TP-121 Development, Calibration and Application of
Runoff Forecasting Models for the Allegheny River Basin
TP-122 The Estimation of Rainfall for Flood Forecasting Using Radar and Rain Gage Data
TP-123 Developing and Managing a Comprehensive Reservoir Analysis Model
TP-124 Review of U.S. Army corps of Engineering Involvement With Alluvial Fan Flooding Problems
TP-125 An Integrated Software Package for Flood Damage Analysis
TP-126 The Value and Depreciation of Existing Facilities: The Case of Reservoirs
TP-127 Floodplain-Management Plan Enumeration TP-128 Two-Dimensional Floodplain Modeling TP-129 Status and New Capabilities of Computer Program
HEC-6: "Scour and Deposition in Rivers and Reservoirs"
TP-130 Estimating Sediment Delivery and Yield on Alluvial Fans
TP-131 Hydrologic Aspects of Flood Warning - Preparedness Programs
TP-132 Twenty-five Years of Developing, Distributing, and Supporting Hydrologic Engineering Computer Programs
TP-133 Predicting Deposition Patterns in Small Basins TP-134 Annual Extreme Lake Elevations by Total
Probability Theorem TP-135 A Muskingum-Cunge Channel Flow Routing
Method for Drainage Networks TP-136 Prescriptive Reservoir System Analysis Model -
Missouri River System Application TP-137 A Generalized Simulation Model for Reservoir
System Analysis TP-138 The HEC NexGen Software Development Project TP-139 Issues for Applications Developers TP-140 HEC-2 Water Surface Profiles Program TP-141 HEC Models for Urban Hydrologic Analysis
TP-142 Systems Analysis Applications at the Hydrologic Engineering Center
TP-143 Runoff Prediction Uncertainty for Ungauged Agricultural Watersheds
TP-144 Review of GIS Applications in Hydrologic Modeling
TP-145 Application of Rainfall-Runoff Simulation for Flood Forecasting
TP-146 Application of the HEC Prescriptive Reservoir Model in the Columbia River Systems
TP-147 HEC River Analysis System (HEC-RAS) TP-148 HEC-6: Reservoir Sediment Control Applications TP-149 The Hydrologic Modeling System (HEC-HMS):
Design and Development Issues TP-150 The HEC Hydrologic Modeling System TP-151 Bridge Hydraulic Analysis with HEC-RAS TP-152 Use of Land Surface Erosion Techniques with
Stream Channel Sediment Models
TP-153 Risk-Based Analysis for Corps Flood Project Studies - A Status Report
TP-154 Modeling Water-Resource Systems for Water Quality Management
TP-155 Runoff simulation Using Radar Rainfall Data TP-156 Status of HEC Next Generation Software
Development TP-157 Unsteady Flow Model for Forecasting Missouri and
Mississippi Rivers TP-158 Corps Water Management System (CWMS) TP-159 Some History and Hydrology of the Panama Canal TP-160 Application of Risk-Based Analysis to Planning
Reservoir and Levee Flood Damage Reduction Systems
TP-161 Corps Water Management System - Capabilities and Implementation Status
