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UTAH GEOLOGICAL AND MINERAL SURVEY
REPORT OF INVESTIGATION
NO. 197
DAM FAILURE INUNDATION STUDY FOR DEER CREEK DAM, UT~H COUNTY
by William F. Case
Applied Geology Group
March 1985
Work performed as part of the Earthquake Hazard,Reduction Program of the Utah Geological and Mineral Survey
FORWARD
A principal objective of the Utah Geological and Mineral Survey is the
identification of areas of Utah that are exposed to geologic hazards.
Geologic events such as earthquakes, landslides, and debris flows can cause
dams to fail and produce flooding downstream. Inundation mapping is thus an
essential ingredient.in any comprehensive hazard mapping effort. Deer Creek
Dam was chosen for this inundation study, the first by the Utah Geological and
Mineral Survey (UGMS), because of special interest expressed by the State
Division of Comprehensive Emergency Management and the Utah County Office of
Emergency Preparedness. The reservoir is one of the more significant water
impoundments along the Wasatch Front and would impact a considerable
population if it were to fail. Because topographic maps of Provo River
Canyon, downstream from the dam, are exceptional in scale and contour
interval, a more accurate inundation map can be produced here than would be
possible in most areas.
This report is intended to present the results of the inundation study and
to document the procedures adopted by the UGMS in the preparation of
inundation area maps. A byproduct of this study is the travel time of the
released reservoir water as it moves downstream. With this information,
emergency preparedness personnel may estimate time available for escape along
evacuation routes. Shelter zones can be established when the potential
inundation zone is determined. Potential inundation is but one hazard that
must be considered in the siting of critical facilities. It is one hazard,
however, that is commonly ignored by both public and private sectors.
I join Mr. Case in extending our gratitude to the U. S. Bureau of
Reclamation for their kind assistance with this study.
Bruce N. Kaliser
State Hazard Geologist
CONTENTS
Forward • • • •
Acknowledgments • •
Introduction
Hydrodynamic analysis • •
Discussion
Cited references
Appendix
ILLUSTRATIONS
Plate 1. Inundated area resulting from a postulated worst-case scenario: Deer Creek Dam failure Provo River, Utah •••••••••••••
Figure 1. Index and location map of Provo River Basin
Figure 2. Diagrammatic longitudinal profile of
• front
1
1
7
• 14
•• 20
• 21
.12-13
• . • .2
Provo River • . • • • • • • • • • • • • • • • • • • .6
TABLES
Table 1. List of Provo River flood obstructions •
Table A-I. Cross-section data • • • • • • • • • •
• 16-17
•• 22-23
ACKNOWLEDGMENTS
I would like to thank the Utah County Flood Control office and the Utah
State Department of Transportation. for the use of their large-scale maps of
the study area. The Utah State Department of Comprehensive Emergency
Management has provided necessary support and assistance. The Bureau of
Reclamation, specifically Brent D. Taylor, has provided technical assistance
which has made this report possible. Any errors, conceptuai or arithmetic,
are the author's.
INTRODUCTION
Deer Creek Dam is an earthfill dam on the Provo River in the Wasatch Range
east of Utah Valley. The Provo River originates in the western part of Unita
Mountains and flows in a northwesterly direction to Utah Lake. The natural
flow of the Provo River is augmented by water diverted from the North Fork of
the Duchesne River and the Weber River. The Deer Creek Dam is part of the
Provo River Project, which delivers Provo River water to metropolitan areas of
Utah and Salt Lake Counties. Deer Creek Reservoir, formed by the dam, has a
capacity of 152,000 acre-feet. Downstream from the dam the Provo River flows
through Orem and Provo. The dam provides flood protection for these
communities, but if the dam should fail and release water from Deer Creek
Reservoir into the Provo River, parts of these communities would be
inundated. The purpose of the study reported here was to determine the area
that would be inundated by an instantaneous failure of Deer Creek Dam with the
reservoir filled to capacity--the worst-case scenario.
The study area extends from Deer Creek Dam to Utah Lake, 20.3 river miles
(mileage along streambed, from dam) downstream along the Provo River (fig. 1).
U.S. Highway 189 which connects Provo, Utah with Evanston, Wyoming (via
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CANALS
A. Sal t Lake Aqueduct
B. Provo Reservoir Canal
c. North Union Canal
D. West Union Canal
E. Lake Bottom Canal
F. Lower Union Conal
G. Upper Union Canal
H. Tlrnpanogos Canal
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DEER" CREEK DAM
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I. Duchesne Tunnel Figure I: INDEX & LOCATION MAP OF PROVO RIVER BASIN
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-3-
Interstate 80) runs parallel to the Provo River in the study area. Utah
Highway 92, the "Alpine Loop" from American Fork which terminates at Wildwood
and Highway 189 approximtely 4 miles below Deer Creek Dam, is the only other
transportation route out of the Provo River Canyon. The tributaries that flow
into the Provo River in the study area are as follows: A) Provo Deer Creek
(river mile 0.74) has an approximate maximum discharge on the order of 100
sec.-ft. (Butler, 1966); B) North Fork, which enters the Provo River at
Wildwood (river mile 3.95) has an approximate maximum discharge of about 225
sec.-ft. (Butler, 1966); and C) South Fork which enters the Provo River at
Vivian Park (river mile 5.32) has an approximate maximum discharge of 125
sec.-ft. (Butler, 1966).
The headlands of the Provo River are in the Uinta Mountains approximately
40 miles east of Deer Creek Dam. Water is transferred from the North Fork of
the Duchesne River to the Provo River through the Duchesne Tunnel (Ion fig.
1) and from the Weber River along the Weber-Provo canal (fig. 1). The
Duchesne Tunnel has a capacity of 600 sec.-ft. and the Weber-Provo canal can
route 1000 sec.-ft. The drainage area of the Provo River above the mouth of
Provo Canyon (river mile 11) to Deer Creek Dam (river mile 0.00) is 666 sq.
mi. (Corps of Engineers, 1971). The Corps of Engineers (1971) has defined the
peak discharge of the Intermediate Regional Flood (IOO-yr flood) to be 3000
sec.-ft. and the peak discharge of the Standard Project Flood ("The most
severe combination of meteorological conditions reasonably characteristic of
the geographical region, excluding extremely rare combinations") to be 5200
sec.-ft. at the mouth of Provo Canyon. Peak discharges of the Provo River
(Corps of 'Engineers, 1971) are approximtely 2200 sec.-ft. at Deer Creek Dam
3200 sec.-ft. at Vivian Park (river mile 5.32) and 2500 sec.-ft. at Provo,
1300 feet downstream from the bridge at Highway 114 (river mile 17.67).
-4-
Most of the population that would be affected by a fiood on the Provo
River live in Utah County, downstream from the county line at Wildwood (river
mile 3.95). Canyon Meadows Sales Offices (river mile 1), Deer Creek Park
Campground (river mile 0.75), and residential buildings along Provo Deer Creek
are the only populated zones in Wasatch County, upstream from Wildwood, that
would be affected by a flood due to Deer Creek Dam failure. A flood along the
Provo River below Deer Creek Dam would affect people in the cities of Orem and
Provo which have a 1980 census population of 52,399 and 73,907 respectively,
and represent 58 percent of the population of Utah County. A flood of the
magnitude suggested by this report is expected to indirectly affect at least
100,000 people due to disruption of lifelines. The residential areas
downstream from the Utah County line to the canyon mouth include Wildwood
(river mile 3.95), Vivian Park (river 5.32), Canyon Glen (river mile 8.2) and
Springdell (river mile 8.6). Commercial facilities include River Bend Trailer
Park and a general store (riyer mile 5.05), Bridal Veil Falls tram, etc.
(river mile 7.15) and a cafe near Wicks (river mile 9.3). Industrial
facilities in the Provo River Canyon include a gravel pit (river mile 10.5 )
and Utah Power and Light hydropower plant at Olmstead in the mouth of the
canyon (river mile 10.8). A hydropower plant at the base of Deer Creek Dam
can release 1500 sec.-ft. into the Provo River, enough to cause slight
flooding damage in Provo River Canyon. The water transmission facilities
(fig. 1) within Provo River Canyon are the Salt Lake City (Deer Creek)
Aqueduct (A on fig. 1) which has a capacity of 150 sec.-ft. and routes water
from Deer Creek Dam to Salt Lake City, the Provo Reservoir Canal/Murdock Canal
(B on fig. 1) which routes water from Murdock/Olmstead diversion dam to the
west side of Jordan River Valley, and the Union Canal (not shown on fig. 1)
which provides Provo River water to the Olmstead hydropower plant. The
-5-
Murdock/Olmstead dam is a gravity dam which diverts approximately 550 sec.-ft~
into the Jordan River Valley. Below the canyon mouth 6 canals distribute
water along the Wasatch Front (fig. 1), water is routed to the north by the
North Union (C on fig. 1), West Union (0 on fig. 1), and Lake Bottom (E on
fig. 1) canals, and to the south water is routed by the Lower Union (F on fig.
1), Upper Union (G on fig. 1), and Timpanogos (H on fig. 1) canals. The Provo
River, after leaving the canyon, passes through the communities of Orem,
Caryhurst, Edgemont, Pleasant View, and Provo on its way to Utah Lake State
Park. The elevation range of the study area is from 5425 feet at Deer Creek
Dam crest to about 4490 feet at Utah Lake.
The geology of Provo River Canyon in the study area is examined to
estimate the resistance to hydraulic erosion of the streambed and valley
walls. Erosion as defined for the purpose of this report consists of removal
of sediment and bedrock by 1) abrasion by transported materials within flood
waters such as sand, trees, boulders, etc.; 2) hydraulic plucking or
dislodging of sediment and bedrock by flood water pressure; and 3) solution of
geologic units by water. Three age groups are represented in the canyon:
A) Quaternary-age sediments, which are less than 1.8 million years old;
B) Pennsylvanian-age sedimentary rocks (320 to 280 million years old); and
C) Mississippian-age sedimentary rocks that were deposited before the
Pennsylvanian rocks but after 345 million years ago. The geologic formations
in the study area are Great Blue Limestone (Mississippian age), Manning Canyon
Shale (late Mississippian or early Pennsylvanian age) and Oquirrh Formation of
Pennsylvanian age which is basically sandstone with Bridal Veil Limestone
Member.
The Quaternary sediments are unconsolidated or semiconsolidated and are
classified by the agent that deposited them (fig. 2): Qal is alluvium/valley
-6-
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fill (stream deposit), Qow is glacial outwash (glacial sediments deposited by
meltwater), and Qls is a landslide deposit. The first letter or symbol is an
abbreviation for the age of the unit, i.e., Q = Quaternary, M = Mississippian,
P = Pennsylvanian, PM = Late Mississippian/Early Pennsylvanian.
The erosion resistance of geologic units is a function of: 1) age, younger
sediments or rocks are normally less lithified and thus more easily eroded; 2)
rock type, in a semi-arid climate (the average annual precipitation at Deer
Creek Dam is 23 inches, and at Provo and Utah Lake is 16 inches) limestone is
very resistant, and will erode into massive blocks the size of which may be
controlled by "joints" (fractures in rock caused by similar tectonic forces
that produce faults but which do not result in the slippage characteristic of
faults), sandstone has moderate resistance, and shale is relatively soft; and
3) density of faulting, an area of intense faulting will have more crushed
rock which is easier to erode. The geologic units,shown on figure 2 are in • the immediate vicinity of the streambed. It is not known how thick the
streambed (Quaternary) deposits are in the channel but for a dam failure flood
discharge, such as described in this report, the channel in Provo River Canyon
is likely to be scoured to bedrock throughout its length. Shroba (1979)
reports that the Big Thompson Canyon flood of July 31, 1976 scoured the creeks
to bedrock for the length of the canyon, with a flood discharge only 4 percent
(31,200 sec.-ft.) of the discharge postulated in this report (845,619
sec.-ft.). Silt, sand, and gravel will be available for flood transport in
varying proportions from all the Quaternary deposits along Provo River
Canyon. Larger blocks will come from bedrock, with limestone yielding the
largest blocks.
HYDRODYNAMIC ANALYSIS
Potential causes of dam failure include overtopping of flood waters over
-8-
the dam crest, damage to the structure or foundation due to earthquake
shaking, or foundation failure due to piping. Earth dams, such as Deer Creek
Dam, may develop a breach that enlarges gradually due to overtopping or
piping. The time required for the enlargement of the breach to its maximum
size (resulting in the peak flood discharge) may be a few minutes or several
hours depending on a multitude of factors including reservoir storage and
depth of water behind the dam at the time of failure. Peak depth of flood
waters and time to peak discharge just below the dam depend on the breach
size, shape, and development time among other factors.
In order to produce an inundation overlay and data layer for a seismic
hazard zonation model a worst-case scenario is assumed. The maximum inundated
area along the Provo River due to a failure of Deer Creek Dam is utilized.
The dam breach is equal to the size of the dam. The reservoir is assumed to
be full. Inflow to the reservoir will not be considered because it is minor
(less than 1 percent) compared to the magnitude of the dam failure flood
discharge. Butler (1966) gives the maximum discharge for the Provo River
directly upstream from the reservoir to be approx~mately 1700 sec.-ft., 0.2
percent of the calculated flood-wave discharge at the dam (845,619 sec.-ft.)
due to a hypothetical dam failure. Tributary inflow downstream from·the dam
was not considered because it, also, is minor (less than 0.1 percent) compared
to the calculated dam failure flood discharge.
Emergency plans for evacuation and shelter require not only the
geographical extent of flooding but also the minimum amount of time available
for evacuation. Because the maximum flood and minimum travel time is desired
for this analysis the entire Deer Creek Dam is assumed to fail
instantaneously. This postulated event is believed to be extremely
improbable. The following analysis will attempt to show the maximum
inundation area along the Provo River from Deer Creek Dam to Utah Lake and the
-9-
expected flood-wave arrival time at various localities assuming the worst
conceivable scenario.
The procedures used for estimating peak discharge at the dam and the
attenuation of the flood-wave discharge as it moves downstream are based on
Bureau of Reclamation 'Guidelines for Defining Inundated Areas Downstream from
Bureau of Reclamation Dams' (1982). The Bureau of Reclamation equation for
estimating peak discharge at the dam, in sec.-ft., is: Q = 75(0)1.85, where
Q is the peak discharge and D is the depth of the water in feet behind the dam
at the time of failure which, in this study, is equal to the design hydraulic
height of Deer Creek Dam, 155 feet. The calculated peak discharge, Q, using
this equation is 845,619 sec.-ft. The equation for estimating downstream
discharge attenuation, Qx, is: Qx = 10 (log Q-O.OlXY, where Qx is the
calculated peak discharge in sec.-ft., x miles below the dam. The equations
for Q and Qxare empirical and were derived from data compiled by the Bureau
of Reclamation (1982).
Cross-sections were drawn at intervals along the valley to characterize
the hydraulic properties of the valley, for example at constrictions or change
in slope, in order to accurately determine the inundated areas along the river
and to determine the extent of potential flood water encroachment on geologic
hazards such as landslides. The shape of each cross-section was approximated
by trapezoidal sub-sections to simplify determination of cross-sectional area
and wetted-perimeter (cumulative length of channel sides and. bottom in contact
with floodwater). Many analyses assume the wetted perimeter is basically the
same as the width of the channel, however, because of the large-scale maps
that were available the channel sides were considered as part of the wetted
perimeter. Each trapezoidal sub-section was defined by a top- and
bottom-width and their respective elevations. The bottom-width of the initial
trapezoidal sub-section for each cross-section is the width of the streambed.
-10-
The discharge for each trapezoidal cross-section was calculated using Man~ings
equation for open-channel flow. The depth in the cross-section approximation
is increased until the calculated discharge is contained.
Mannings equation calculates cross-sectional discharge (Qs) as a function
of: A) n, a parameter characterizing net channel roughness, which is assumed
to be 0.035 in this study, the average value for natural channels according to
Linsley (1975); B) s, the topographical gradient of the streambed from the
closest upstream cross-section in vertical feet/horizontal feet; C) A, the
area of the cross-section in square feet; and D) R, the hydraulic radius of
the cross-section, in feet (the cross-sectional area A, divided by the
wetted-perimeter of the cross-section). The discharge through the
cross-section, Qs, is calculated from Mannings equation where Qs = (1.49/n)
(s)1/2(R)2/3(A), in sec.-ft. Code for a hand-held calculator used to
compute the peak flood-level elevation at each cross-section. Results
compared favorably with the National Weather Service (NWS) Simplified Dambreak
Program (SMPOBK). This elevation defines the maximum inundation at the
cross-section.
The peak flood elevations and inundated areas between cross-sections is
subject to interpretation and must be interpolated using hydraulic logic from
values calculated at cross-sections. In a straight channel the water surface
is relatively level, i.e., the water surface is at the same elevation on both
banks. A curved pathway such as in a natural meander introduces a centrifugal
force on the flowing water mass resulting in higher water on the outside of
the bend and lower water on the inside of the bend than would occur with a
straight channel. Flood waters tend to back upstream as a result of valley
constrictions. Increased channel-bottom resistance also increases depth of
flood waters due to the fact that vegetation or buildings reduce the velocity
of flood waters.
-11-
The average yelocity of flow at the cross-section, in feet/second, is
equal to the discharge, Qs, divided by the area, A. Travel times of the flood
crest are estimated because of the number of variables that can influence
velocity.
The topographic base maps used are from the Utah State Department of
Transportation (UDOT) and Utah County. Flood Control Office. The UDOT maps are
at a scale 1 inch'= 100 feet with a contour interval of 2 feet and cover the
Provo River Canyon from Deer Creek Dam to the canyon mouth, about 11 river
miles. The Utah County maps have a contour interval of 5 feet, a scale 1 inch
= 500 feet, and cover the drainage area from the canyon mouth to Utah Lake,
about 9 river miles. It should be noted that the topographic maps used were
drafted before the recent (1983-84) increase in precipitation in the Provo
River area, therefore the topography of the river valley may have changed
slightly.
Sixteen cross-sections, tfrom #1 at the base of Deer Creek Dam spillway to
#16 at Utah Lake State Park, were drawn across the Provo River at specific
locations (plate 1). Flood-wave crest elevations have been calculated and
plotted on plate 1 for all cross-sections except 1 and 16. Cross-section 1
(river mile 0.00) is at the base of the dam 0.16 miles upstream from 2.
Cross-section 16 (river mile 20.14) extends from the Utah Lake shoreline on
one end to the shoreline on the other end of the section across the Provo
River delta. By the time the flood-wave. arrives at cross-section 16 it will
have exceeded the width of the section therefore the height cannot be
calculated. Cross-sections 2, 4, 5, 7, 12, 13, 14, 15 were located to
characterize Provo River Canyon hydraulic parameters. Populated areas in the
canyon and on the flood plain are covered by cross-sections 2, 3, 6, 8, 10,
11, 13, 14, and 15 (note: some cross-sections are multi-purpose). Cross-
-14-
sections 9, 10, 11 are at locations of landslides and, glacial outwash.
Cross-section widths range from 419 feet (7) to 6464 feet (15) and the depth
of the flood-wave ranges from 25 feet at section 15 (the widest cross-section)
to 83 feet at cross-section 9 which has the most gentle channel-bed slope
along the study reach, 10 ft/mile. Just downstream, at cross-sections 10 and
11, the slopes are 83 ft/mile and 90 ft/mile, the steepest slopes.
Cross-section 10 will have the highest average velocity of flood waters, 36
mph (53 ft/s). All cross-section plots showing the flood-wave crest
elevation, geology, and diagrammatic topography are in appendix A. Table A-I
in appendix A is a compilation of relevant data used for calculations for each
cross-section'. All top-widths used in the hydraulic calculations were picked
at a topographic threshold if evident (where a channel suddenly widens as the
water level rises), or to characterize the slope of valley walls. The
smallest top-width and lowest elevation of the cross-section represent the
present channel width and streambed elevation as estimated within the contour
interval of the base maps.
DISCUSSION
Plate 1 shows the extent of the inundation of Deer Creek Reservoir waters
from Deer Creek Dam to Utah Lake. Table 1 lists known ob~tructians in the
study area, their height above the streambed, and the height of the expected
flood-wave above the obstruction. Examples of obstructions include: bridges
(foot, vehicle, or railroad), weirs, diversion dams, viaducts, and abutments
of dismantled structures. The only feature that would not be overtopped by
the calculated flood-wave is the bridge at West Center Street (river mile
20.05), however, if the flow velocity is greater than 3 mph (hydraulic
calculations indicate that flow velocities would be approximately 10 mph) the
-15-
Table 1. List of Provo River Flood Obstructions (from Corps of Engineers, 1971 & 1972)
Top Approx. Flood Approx. Flood River Elev. -wave Crest Height Above
Obstruction Mile (ft. ) Elev. (ft.) Feature (ft.)
Vehicle bridge 0.40 5280 5330 50 Foot bridge 0.84 5261 5310 49 Foot bridge 0.88 5261 5310 49 Railroad bridge 2.77 5232 5310 78 yehicle bridge,
Vivian Park 5.15 5197 5220 23 Union Aqueduct
diversion 6.11 5194 5270 76 Foot bridge 6.55 5159 5220 61 Foot bridge, Bridal
Veil Falls 7.22 5110 5165 55 HWY 189 bridge 7.63 5060 5110 50 Foot bridge 7.76 5042 5080 38 Railroad bridge 8.35 4995 5020 25 Vehicle bridge . 9.88 4897 4910 13 Murdock diversion
dam 10.00 4886 4900 13 Railroad bridge,
abandoned 10.88 4827 4850 23 Timpanogos Canal
diversion 10.89 4820 4850 30 Upper Union Canal
diversion 10.90 4816 4850 34 North Union Canal
diversion 10.94 4815 4845 30 Unnamed canal
diversion 10.98 4820 4845 25 8th North, Orem
bridge 11.07 4821 4840 19 Railroad bridge 11.27 4800 4825 25 West Union canal
diversion 11.36 4791 4820 29 Carterville Road
bridge 11.54 4791 4810 19 Center St., Orem
abutment 12.21 4745 4770 25 3700 N, Provo
bridge 13.33 4701 4715 14 Riverside Golf
Course bridge 14.33 4650 4665 15 Lake Bottom canal
diversion 14.55 4630 4655 25 Lower Union Canal
diversion & bridge 14.75 4623 4645 22 BYU diagonal: east 14.96 4620 4635 15 BYU diagonal: west 14.98 4619 4635 16 HWY 89-91 bridge 15.60 4590 4605 15
-16-
Table 1. List of Provo River Flood Obstructions - Continued.
Columbia Lane bridge 15.72 4592 4595 3 Weir 15.73 4581 4595 14 9th No, Provo
bridge 16.10 4573 4585 12 8th No, Provo
bridge 16.19 4572 4580 8 D&RGW rail abut-
ments 16.94 4527 4555 28 D&RGW rail- bridge 16.98 4539 4550 11 U.P. railroad
bridge 17.04 4543 4550 7 1-15 HWY bridge 17.12 4537 4545 8 Weir 17.15 4518 4545 27 HWY 114 bridge 17.42 4523 4535 12 West Center st.
bridge 20.05 4497 4495 -3 Utah Lake State
Park bridge 20.17 4490 4495 5
-17-
bridge piers could be washed out due to erosion of surrounding fill (Corps of
Engineers, 1972). Another type of obstruction that occurs in the study area
is the embankment of Interstate 15. Although it is estimated that the flood
waters may overtop the embankment (table 1) some water would back up on the
upslope side of the embankment and would flow to the northwest and southeast
(plate 1). Once this water reaches an overpass it would flow through the
overpass at a high velocity, particularly if the surface is paved. The
"breaks" in the 1-15 embankment through which flood waters would flow include
the overpass over the railroad tracks about 9th North in Provo, the Center
Street overpass, and the intersection of University Avenue and Interstate 15.
The ponding upslope of the 1-15 embankment would likely extend well into
Provo. Below the city and the embankment the flood waters would fan out and
deposit debris across the Utah Lake plain.
As a result of flood waters from a Deer Creek Dam failure, the water level
in Utah Lake may temporarily rise above an elevation of 4490 foot. The
projected maximum water surface elevation increase in Utah Lake would be about
8 inches. If the Jordan River gates were open it is likely that areas along
the Jordan River would be flooded although the consequent rise in the Great
Salt Lake would be minimal.
water flowing out of the canyon mouth below the constriction at
cross-section 12 would spread out between two bluffs and, as the flooded
'channel effectively widens below the mouth of Provo River Canyon, flow
velocities would steadily decrease. The average velocity of flood waters
through cross-section 12 (narrow canyon mouth) would be about 30 mph. As the
flooded channel widens the velocities would decrease progressively to 10 mph
at section 15 in Provo City. Once the flood waters leave cross-section 15
(river mile 15.63) they would spread out because they are no longer contained
-18-
by the river'bluffs. Locally the velocity would be higher, for example, over
paved streets, through local constrictions, etc. The velocities in the bluff
area would be of the same magnitude as those in the steepest reaches of the
Big Thompson Canyon flood in Colorado in 1976 (Shroba, 1979). With such high
velocities one would expect similar damage, that is, vehicles smashed beyond
recognition, wood frame houses torn off foundations, masonry buildings
destroyed by debris acting as battering rams, deposition of very
large-diameter debris (natural and man made) in bars nearly 20 feet thick.
All transportation routes within the bluff area (cross-sections 12'to 15) and
within the Provo River Canyon (cross-sections 1 to 11) would be severed. The
bluffs themselves would be undercut and slopes would fail severing the canals
on top. The canals near the mouth of Provo River Canyon would probably be
breached early in the flood and therefore would not likely route flood water
beyond the postulated area of inundation. The Olmstead hydropower plant would
be taken out of service by the flood waters. It would take about one-half
hour, after dam failure for the flood-wave (a 38-foot-high wall of water
loaded with diverse debris) to reach the mouth of the canyon.
Upstream, within the Provo River Canyon, the flood waters would scour the
canyon to bedrock or below depending on local conditions. Sediment that has
been picked up is. usually deposited just downstream in the next area of slack
water, except for floating material that wasn't tangled up. The flood waters
would undercut most of·the highway fill and railroad fill, and near
cross-section 9, would sever the Salt Lake City Aqueduct and the Union
Aqueduct. All Provo River Canyon communities and facilities would be
flooded. The flood waters would back up approximately 1200 feet into North
Fork (at Wildwood) and probably would back 1000 feet up the South Fork into
Vivian Park. New landslides would be initiated due to bank undercutting and
channel scour by the flood and old landslides would be rejuvenated.
-19-
It would take approximately 10 minutes (after dam failure) for the
flood-wave to reach Wildwood, the first vehicle escape route out of the
canyon. In about 15 more minutes the flood-wave would be at the canyon mouth
and approximately 90 minutes after the dam failure flood waters would reach
Utah Lake. The average velocity of the flood waters from Deer Creek Dam to
Utah Lake would be approximately 15 mph.
Facts that should be considered while planning emergency responses should
include the following:
A) People in the Provo River Canyon should not try to drive out of the
canyon, but instead should head for high ground. A warning system
should be installed in the canyon, one that is not dependent on
normal communication channels (telephone or CB). People in the
canyon will have less than 1/2 hour to save themselves.
B) Refugee areas would likely be on the northwest and southeast sides of
Provo River, the bench at Orem and the BYU campus plateau. North
south highways will be severed. The evacuation paths should be
east-west. Even after flood waters have subsided normal
transportation routes will be clogged with sediment and debris.
C) Evacuation time below the canyon mouth would range from one-half to
one hour.
D) All lifelines (phone, sewer, water, power, gas) may be severed or
contaminated. The sewer treatment plants (Timpanogos, Orem, & Provo
City) may become inoperative. Administrative operations may have to
be moved from Provo.
-20-
CITED REFERENCES
Baker, Arthur A., 1964a, Geology of the Aspen Grove Quadrangle, Utah: United states Geological Survey Geologic Quadrangle Map GQ-239.
------1964b, Geology of the Orem Quadrangle, Utah: United states Geological Survey Geologic Quadrangle Map GQ-241.
------1972, Geologic map of the Bridal Veil Falls Quadrangle, Utah: United states Geological Survey Geologic Quadrangle Map GQ-998.
Bureau of Reclamation, 1982, Guidelines for defining inundated areas downstream from Bureau of Reclamation dams; Bureau of Reclamation unpublished report.
Butler, E., J.K. Reid, V.K. Berwick, 1966, Magnitude and frequency of floods in the United States: Part 10, the Great Basin: United States Geological Survey Water Supply Paper 1684, 256 pp.
Corps of Engineers, 1971, Flood plain information Provo River and Rock Canyon Creek, Provo and Orem, Utah: Department of the Army, Sacramento District, 34 pp.
---~--1972, Flood plain information Provo River and Slate Creek, Provo, Utah: Department of the Army, Sacramento District, 34 pp.
Linsley, Ray K., Jr., Max A. Kohler, Joseph L.H. Paulhus, 1975, Hydrology for engineers: McGraw-Hill Publishers.
Shroba, Ralph R., Paul W. Schmidt, Eleanor J. Crosby, and Wallace R. Hansen, 1979, Geologic and geomorphic effects in the Big Thompson Canyon area, Larimer County: United States Geological Survey Professional Paper 1115, pp 87-152.
APPENDIX
Table A-I consists of the top-widths, elevations, slope, and discharge used for the calculations of Flood-wave crest parameters for cross-sections #2 through #15. Diagrammatic representations of cross-sections #2 through #15 follow below the table.
-22-
Table A-I. Cross-Section Data - Continued
TOP ELEVA-WIDTH TION (FT) (FT)
* 35 5178 75 5190
CROSS-SECTION 119 100 5192 FLOOD-WAVE CREST RIVER MILE = 6.26 120 5198 ELEVATION = 5261 feet SLOPE=0.0019 ft/ft 270 5200 PEAK DEPTH = 83 feet PEAK DISCHARGE,Qx= 732,107cfs 298 5208 ARRIVAL TIME = 20 minD
670 5250 AVE. VELOCITY = 15 mph 800 5270
CROSS-SECTION 1110 * 38 5096 FLOOD-WAVE CREST RIVER MILE = 7.25 55 5104 ELEVATION = 5153 feet SLOPE=0.0157 ft/ft 120 5108 PEAK DEPTH = 57 feet PEAK DISCHARGE,Qx= 715,607cfs 210 5114 ARRIVAL TIME = 22 minD
263 5130 AVE. VELOCITY = 36 mph 440 5160
CROSS-SECTION 1111 * 66 4968 FLOOD-WAVE CREST RIVER MILE = 8.68 495 4972 ELEVATION = 4993 feet SLOPE=0.0017 ft/ft 660 4974 PEAK DEPTH = 25 feet PEAK DISCHARGE,Qx= 692,428cfs 746 4990 ARRIVAL TIME = 24.5 minD
790 4993 AVE. VELOCITY = 29 mph
* 33 4826 FLOOD-WAVE CREST CROSS-SECTION #12 50 4828 ELEVATION = 4864 feet RIVER MILE = 10.75 255 4834 PEAK DEPTH = 38 feet SLOPE=0.0013 ft/ft 385 4836 ARRIVAL TIME = 28.5 min# PEAK DISCHARGE,Qx= 660,199cfs 453 4850 AVE. VELOCITY = 31 mph
502 4870
CROSS-SECTION #13 * 40 4796 FLOOD-WAVE CREST RIVER MILE = 11.23 80 4805 ELEVATION = 4828 feet SLOPE=0.0118 ft/ft 310 4810 PEAK DEPTH = 32 feet PEAK DISCHARGE,Qx= 652,942cfs 523 4814 ARRIVAL TIME = 30 minll
1265 4816 AVE. VELOCITY = 20 mph 1340 4825 1378 4850
CROSS-SECTION #14 * 75 4751 FLOOD-WAVE CREST RIVER MILE = 12.11 650 4760 ELEVATION = 4774 feet SLOPE=0.0097 ft/ft 1620 4764 PEAK DEPTH = 23 feet PEAK DISCHARGE,Qx= 639,845cfs 3200 4800 ARRIVAL TIME = 33.5 min#
AVE.VELOCITY = 16 mph
CROSS-SECTION #15 * 80 4575 FLOOD-WAVE CREST RIVER MILE = 15.63 95 4590 ELEVATION = 4600 feet SLOPE=0.0095 ft/ft 1270 4594 PEAK DEPTH = 25 feet PEAK DISCHARGE,Qx= 590,031cfs 6430 -4596 ARRIVAL TIME = 54.5 min#
6464 4600 AVE. VELOCITY = 10 mph 6624 4625
-23-
Table A-I. Cross-Section Data
TOP ELEVA-WIDTH TION (FT) (FT)
* 55 5272 103 5284
CROSS-SECTION #2 340 5286 FLOOD-WAVE CREST RIVER MILE = 0.16 475 5300 ELEVATION =-5347 feet SLOPE=0.0024 ftlft 600 5310 PEAK DEPTH = 75 feet PEAK DISCHARGE,Qx= 842,509cfs 670 5330 ARRIVAL TIME = 0.5 minD
715 5340 AVE.VELOCITY = 15 mph 1900 5360
* 67 5261 75 5262
CROSS-SECTION 113 307 5264 FLOOD-WAVE CREST RIVER MILE = 0.74 480 5266 ELEVATION = 5309 feet SLOPE=0.0036 ftlft 530 5270 PEAK DEPTH = 48 feet PEAK DISCHARGE,Qx= 831,332cfs 580 5274 ARRIVAL TIME = 2.5 minD
656 5294 AVE.VELOCITY = 19 mph 774 5310
* 33 5250 CROSS-SECTION #4 150 5264 FLOOD-WAVE CREST RIVER MILE = 1.34 335 5288 ELEVATION = 5331 feet SLOPE=0.0035 ftlft 420 5314 PEAK DEPTH = 81 feet PEAK DISCHARGE,Qx= 819,926cfs 550 5316 ARRIVAL TIME = 4 mini
613 5340 AVE. VELOCITY = 21 mph
CROSS-SECTION lIS * 70 5212 FLOOD-WAVE CREST RIVER MILE = 3.84 160 5218 ELEVATION = 5293 feet SLOPE=O.0029 ftlft 238 5226 PEAK DEPTH = 81 feet PEAK DISCHARGE,Qx= 774,060cfs 293 5250 ARRIVAL TIME = 11min#
503 5300 AVE. VELOCITY = 21 mph
CROSS-SECTION 116 * 43 5204 FLOOD-WAVE CREST RIVER MILE = 4.20 188 5208 ELEVATION = 5258 feet SLOPE=0.0046 ft/ft 340 5211 PEAK DEPTH = 54 feet PEAK DISCHARGE,Qx= 767,670cfs 485 5240 ARRIVAL TIME = 12.5 mini
604 5280 AVE.VELOCITY = 23 mph
CROSS-SECTION 117 * 35 5198 FLOOD-WAVE CREST RIVER MILE = 4.45 190 5209 ELEVATION = 5274 feet SLOPE=O.0045 ftlft 268 5230 PEAK DEPTH = 76 feet PEAK DISCHARGE,Qx= 763,264cfs 340 5260 ARRIVAL TIME = 13 minD
419 5280 AVE. VELOCITY = 25 mph
CROSS-SECTION #8 * 65 5190 FLOOD-WAVE CREST RIVER MILE = 5.05 ~O 5192 ELEVATION = 5231 feet SLOPE=0.0029 ftlft 570 5196 PEAK DEPTH = 41 feet PEAK DISCHARGE,Qx= 752,792cfs 913 5210 ARRIVAL TIME = 15 minD
1019 5250 AVE. VELOCITY = 16 mph
(Note: * = streambed width and elevation, # = approximate travel time from dam)
E L E 1,,)
A ..,.. I
I o ~'l
F E' e t
5:350
('~u.:., t e r' n ar ) ...
DEER CREEK DAM FAILURE INUNDATION AREA
~ 1 y I ~
! ~~
~: FLOOD l .... IAI..)E CF.:EST ______ ~ --'?-(5347-ft-El;~~ti;~~-----~
\ 75 ft Drep) , j
\ I ! ~:::'~::/:~~;~;'~; ~,~n , ~r, ~ 1 )
~ I ~/ \ I / ~I~
\ II
(sandstone & cherty 1 i rne':.tone)
527~3 - ~
5250 I .::;. 5 o
, 5 '? i
o
QuaternarY Alluvium (sand a~d oravel) , -
I
::::~
g
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 2: River Mi le=0.16
- 1 H' t 1 ~ca €os: orlzon.a = 1 : ~:281, l.)e r' tic a 1 = 1: 41 (1 ; t,)e r' tic .:.. 1
-'-
::'1
E ! J....
E t) A T I [I j' .. J
F e e t
531.:;. DEER CREEK DAM FAILURE INUNDATION AREA
!
i ,--~~~~~-~~:~-~~~~~-:~~~:-:!-~~~~~!~~~~-~~-:!-~~~~~------------------J
5:30:3 - \ I !
'\ I / I . 5:300 - ! /
52E:4 -
526(1
I I " ! -.~ I f \ ! / \ I I \ I I \ I f \ I : \ I J
\ ! J
G!u .~. t e r' n .~.r·)t" All u v i UrT! ( ·:·a.n d ,£" I~r' .~I.) E' 1 )
! .-. ~~I
1 ~3
I 1 c-'-' c-._I
7 7
I ~
I -// I ~.
I !
L ~.j
PRI~ll.)O R I l)E~:
(t, .. lic:lth~ feet)
7 7
! I 1 .--::'
"'-c- .-, '-' .:., c-._1 2
.-, .:t 1 ~1
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 3: River Ml le=0.74
--
~
F E' E' t
5340 \ DEER CREEr< DAt'l FA I lURE I t···JUNDAT I ON AF~EA jf
\ I f 5:=1:3 ~J • 5 - \ - -: ~ ~ ~ ~ - t::!~': § - ~ ~ §~:: - ~ ~ ~ ~.:. - i!.: -§ ~ ::1:: ~! ~ ~ ~.: -§.:. -i!.: - ~:::: ~ ~ -- -- -- -- --- --/
W i .• -( . f
f 5:321 - \ 1 I
8 J 5] 11 .5
527:3.5 -
5254.5 -
5245
\ I~ \ I \ I \ I
\ / \ f \ I \ j
\ I .1. \ /~
f It ···-:o··\ It" 1+"'-'" ,:c. U I., : ) a. IJ "I..:" )
Pe rm i .~rl.'/ Penns;,.'l IJan i .:-.n
\ / Penn'::.}"1 I .... ·:«on i .~n.·"" \
R // t"l i·::,·:. i ·::,S· i I) P i ·~,n A
~;~;;;;g;;~:A:~~~\y ~ ~ g / MANNING CANYON SHALE " A D/" \D /
\ / , / Quaternary, I / Quaternary
All u v i UTTr 'x I J(/ I I I ~1
PRO'·.)!] F.: P.)ER
Al1u 1.} j UTTr
(I..· . .lidth~ teet)
I 1 ~ '-'
( '::··~,n d g~
DIAGRA~~ATIC REPRESENTATION OF CROSS-SECTION # 4: River Mi le=l .34
Scales: Horizontal= 1:1057~ Vertical= 1:195 ;Vertical Exaggeration=5x
E L E ! I ",,,'
A T I n t::-J
F e e t
"'"'\ DEER CPEEN DAt"1 FA I L(J F.: E I NUNDAT ION AREA j'" 5:3€H3 \ I
52-;:$1 -
527:3
52.54 -
C"-.C'C' -._'.:, . ..)._'
5246 -
522:3 -
521 ~3
\ FLOOD WAVE CREST (5293 ft. ELEGATON, 81 ft. Deep) /
\ ------------------------------...;.-,,-----.;..--------------------------j
\
1 I I I
\ I / \ I I \ I I
\ I I \ I I \ I / \ I /
\ 1 /
\ I I \ ~
\ I / i\ ·1 / 1 IT IJ \ ! J,;. .:. "\ I r , ! I u
\ : I .:. PEon n s y 1 I.) a. n ian \ I IF' e n n .:. >' 1 I.) .:c. n j .? '-1
OQUI F~RH
F I] Rt"lA T I ON
(·:.andstone & 1 i mestone)
! 2 ~1
i
\ ! J \ I /OQUIRRH
\ H I I FORt"'1AT I ot···J
\ Y I ~ / ~ 1 I [)
~i I § / i A / I Dx
Quaternary I Quaternary
Al l1J'.} i um
I 1 C'
--' 1
! 1 ~1
i
! 5 a
I
I '€I
PF.:Ot)O RIt)ER
(1.-".1 i dth. fee t)
I 5 f1
A! 1 u I.} i urn
I I
1 ~3 1
t ; 1 t:: ._1
1
-,.-(1 ; l.
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 5: River Hi 1e=3.84
Scales: Horizontal= 1:1732~ Vertical= 1:185 :Vertical Exaggeration=9x
2: --,
E l E ! .. )
A T I n r:::-J
e e t
5280 DEER CREEK DAM FAIL~RE INUNDATION AREA ,
~\ ! ! I !
\ I / \ I f \ I I \ I I \ I ! \ I i , FLOOD WAVE CREST (5258 ft. El~vation. 54 ft. Deep) t \------------------------------~------~-----------~----------1
\ I I , I I \ f
\ I /
5272
5264 -
525.:· -
524:3 -
\ ! ~ \ I /
\ ! I T \ I
524(1 -
t \ / ~ \ /
\ ! \ ~ f /
5224 -
~· .... ?1~_~ - \ 1 R I - Pennsylvanian 8 d /Pennsylvan i a0
OG!U I F.~F.~H ~ B .---1 OC!U I PPH
52(1 :::! - F o Rt"'lAT ! or···J ~ ! ~------- F 0 Fl'1AT ! OJ···j
52(10 L, .:. o .j 4
I
~ 1
I 1 .::. '-' 1
OIJ.:..terna.r·y~ ! ~ Alluvium~Quaternary (sand & Qravel) ! Alluvium'
- ! I 1 2 ~~1
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 6: River Mi 1e=4.2
E L E
52:3(1 \ DEER CREEI< DAt-1 FAI LllRE INUNDATIor···! AF.:EA /
\ -~~~~~-~~:~-~~~~~-~~~~~-~!:-~~~~~!~~~!-~~-~!:-~!~~~------------- / 5271. 5 - \ . I /
\ I / \ I j
\ I r
\ / 5263 -
5254.5
I..,..' 524,~,- \ / A T I [I \ I t···!5237.5 Pennsyl- \ /~1!'!~~,1~:1-F eo €' t
I.} .~n i an ',' ·:;!.l! , .::;I.! I
OQUIRRH \ , OQUIRRH
FORMATION, \ / FORMATION~
8r' i da 1 ;,.1 €' \ I c' ! ,j .~. L me's r"1 mbe
t).:?.1 e
5220.5 -
5212 -
52~]3. 5
51 '7'5 I 2 1 \3
Limestone \ I Member \ J
\ IT \
R ,I '~1 H A \ ~:~ [/ ~i
F: I
9/ f-I D
QI.J a teo r' n .~r·}' ./ G!IJ.~ter·n.~.r>··
Alluvium
.:: ·:·an d 8-c: 9r·a1.} e 1 )
I I I 1 1 ,-,
c· t!1 ,-,
..::. 4 :3 ~:.
./ ..... ----I~-W"
I I 4 0 :3 PROl)O
R It . ...'EF.: (k1idth, feet)
I 4 '':1 ,_,
All u') i um
! I :3 1 4 "') ....
6
1 I~r ,;:. ;-~
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 7: River Mile=4.45
Scales: Horizontal= 1:724 Vertical= 1 :175 ;Vertical Exaggeration=4x
~ . i ~]
E L E I . .)
A ,.. I
I 1] t···J
F e e t
5250\ DEER CREEl< DAt'l FAIlURE INUNDATION AREA
5243 -\ I
\ i J
\ 1 j l FLOOD WAVE CREST (5231 ft. Elevation, 41 ft. Deep) ) l------------------------------------------------------------------J l I I
522 t? - l I j l I j l J l I j \ I 1 1 !I ~ \ ~
\ I 1
5222
5215 -~ I j
\ ~ I I k A I j ,I I /
520:3 - ~E I R / ,R 1 A / ,r' H I I /
'-'0 I.N I L / "-.U 'y' I R / 52£11 -
Pennsyl van i ~T § I ~ -"'"~nno;Yl -.}.3."; 3.n :t.n ~ '7' I _______ 51'-;4 - OG!UIR~:H FOR~·'1ATIOt'··J ~ I ~_______ OOUIFFH FC:Pt"'1ATICl"'~
I c:-'-' 1 o
Bridal Vale Limestone Member \ 1 ' Bridal Vale Limestone t"1emt,e r'
I 4 a :3
I Quaternary Alluvium (sand & gravel)
I I
I OJ o
I I i 1 0 1 a PRO~)O 0
4 2 RII.,)ER 2 (l,J.,1 i dth ~ fee t)
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION # 8: Rjver Mi le=5.05
Scales: Horizontal= 1:1754~ Vertical= 1:840 ;Vertical ExaQQera~!on=2x
T f , ; I ," i
5 1 o
E
E I.)
A T I o t···J
F eo eo t
5270 DEER CREEK DAM FAILiRE INUNDATION AREA /
\--~~~~~-~~':::~-~~~~~-~~~~:-:!.:-~~~~~!~~~!-~~-:!.:-~~~~:------------j 5250 -
5240 -
5230 -
522~1 -
521 ~j -
5200 -
5190 -
5180 -
5170 I 4 0 0
\ I / \ i l
\, I J \ I /
\ I / \ I /
\ ! / \ ! /
\ I / \ I /
\ I'R / 1)IJ·a t e r' n ·ar· y \ I~ I ~ /
, Y I ~ I \ ~ I g J Pennsylvanian
~ 1 .... ~ ClI]U I RRH FOFl'1AT I or···J
\ I r E:r' i d.:..l !·.).~.l e Lime -:;. t on e i"lembe:'
G 1 ·9.C i .9.1 Ou tlAl.:..sh
( ·:.an d 8-:: gr' .9. V e 1 )
~ I ) 1 I r \ I J If-J
Quaternary Alluvium ( ·:··9.n d ,~~ ';I r' .9. I.) e 1 )
I ! ! .-. .-. 1 . .:, £.. .j ... 4 ·5 ~3 ~~1 (1
I I I :3 (1 :3 ~3 F'ROl.)O ~3
R I t·..JEF: (1..· . .Iidth, feet)
I 1
! .-, ..:. 4 ~3
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION R i I·)er· t"1 i 1 e=·~·. 26
Scales: Horizontal= 1:1375, Vertical= 1:205 ;Vertical Exaggeration=7x
E L E ! ! .,,,'
A T I (I N
F
51 6~~1
515:3
51:3'7' -
5125 -
511:::! -
5111 -
5104 -
5(197
I 2
~
Quater·rtar::..-
131 ae i ,~ 1 Ou tl".Ja sh
All IJ I,' i urn
( ':.artd &: qr' a I.) e 1 )
! 1 7
I 1 ~':' '-' 2
I 4 4
All I,J 1.) j urn
! 4 4
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #10: River Mile=7.25
Scales: Horizontal= 1 :756 ~ Vertical= 1:144 ;Vertical Exaggeratlon=5x
4999 - DEER CREEK DAM FAILURE INUNDATION AREA I I
K FLOOD WAVE CREST (4993 ft. Elevation. 25 ft. Deep) ~ ,-------------------------------------~---------------------------- / , I ~
\ R I / \ T I /
\ L I H i
\
R I !,. ... I J o I 'y' ! A f ~ I:~ ,, _______ -:4
G!IJ.:..tern,:..r'}, ~ I '~ ~Pef"!n.,,·/t·,·1i·=,·=,. Landsl ide MANNING CANYON SHALE
c'-'
( san d .~~ I~ r .:to 1,,1 e 1 ) IJ. u ~. t ern .:to r' Y I X All IJ I,} i IJ IT! - I
I -::. { 6
I'J '1 17 1~3 ~ 5 9 PROVO '8 RIVER
(1,.. . .1 i I::!th ~ fee t)
1 7 '-;-
! 1 5 ~=~
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #11: River Hi le=8.68
Scales: Horizontal= 1:1362, Vertical= 1:174 ;Vertical Exaggeration=8x
=':;=
E L E I,.)
A T I [I N
F
Eo t
DEER CREEK DAM FAILURE INUNDATION AREA
J FLOOD "'lAVE CREST (4864 f to El eJ" t ion. 38 f to Deep) ! \ ------------------------------------------------------------------ J
4855 -
485~3 -
4840 -
4:335 -
4 ,-,·-.= ,~c..._!
I 2 c-,_I
1
\ I I .1
\ I f \ I / \ I j \ I 1 , I r \ f \ I J
\ I / I
! R I
\ 7 I I~ / \ ~ I ,,{ / ~ 2 ! :~: j ____.....D ! ';' ~
______ I """~
t'l i "S.'::. i :,·S· i pp i ·:..n ~ I ~ t"l i ':,':. i ':,':, i ;:I\:' i ,~.r:
" I /" (3~:EAT BLUE GREAT BLUE L I t'lE:3TOr···JE
L, ~ i
I 1 = ,_I
1
""'-... 1,,/ L I f"l E ~=;T Of",J E
Qua t e r' n ar- )'
\)f--l-i--7([ I
I Alluvium (sand &
I I
1~1 F'RO~)O RIt)ER
(1,"'.1 i dth, fee t::.
! r::: '-' (1
9r' ,:r,I.}e 1 )
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #12: River Mile:10.75
Scales: Horizontal= 1:863 , Vertical= 1:103 ;Vertical Exa9geration=8x
5
A T I o N
F e eo t
DEER CREEK DAM FAILURE INUNDATION AREA
I
1 I I
485~3 1 I \ i
4 - - C' _ll I .I~",; .,! " :=::3,_1 I
~ FLOOD WAVE CREST (4828 ft. Elevation, 33 ft. Deep) Y t ~---------------------------------f------------~-----------~-----~-J
\ I '7' / )Ii !,... x
4:320
LaKe Sed[~ents ~ GREAT BLUE G!uater'n':',r':." ~. I ~ t"1i':·si':.:.i;:'D!·;.!!
( ':,.~ n d ,~~ I~ r' .:',',} e 1 ) -.............. II L I j"1 E :=;T cr"-1 E 4:::a35 - -"
I C'
'-' 5 1
G~IJ,3.ter'n,~,r)" " I j Allu',} i UITI (sand & ~ gravel)
I I I ! 1 f.'1 1 :3 PRell) 0 :~: ':;'I ~: II,')EF: ''I
O},.Ii(:lth~ feet)
I I
4 1 ::~
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #13: River Hi le=11 .22
Scales: Horizontal= 1:2373, Vertical= 1:309 ;Vertical Exaggeration=8x
E L E I .. )
A T I o N
F t? e t
DEER CREEK DAM FAILURE INUNDATION AREA 4820 I U
I N 'IC. I I ~
47~35
r~ I I..) ~~
~ § FLOOD Il.JA~)E CRE~3T A ~ ~ ----A--------------------------------I.)----~ ~ D (4774 f t El el.}.;:t. t1i on ,23 f t Dee!:,) E ...,.~
*-4750 -
Quaternary LaKe Quaternarv Sediments (sand & gravel) Sediments
4715 ! 1 .-, .:. .-. 1~
~3
Qu a. t e r' n ar' ~..,... I
Alluvium (sand & I
L, L I .:;. ~'1 :3 2 PR!~!I.)O 4 ~1 R I I·.)EF.~ H
(1, .• ,1 i dth, fee t)
! I
·5 4 o
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #14: River Hi 1e=12.11
S C 24. 1 e s·: H CI r' iz c. n t ·a 1 = 1: 5 5 ~3 1, L.) e r' tic a 1 = 1: 7 1:3 ; I .. ) e r' tic a. 1 E ::< .:.. f~ 9 e r' ·a t i ':1 i: = ~=: ::{
1= [ E I.,) A T I [I 4~,1 '7' • 5 t·,~
Ft. 4550
DEER CREEK DAM FAILURE INUNDATION AREA
F·ROI..)O CITY
I !H I I.}.J ! 'y' I !:3
1 i --' t···j I
I.,)
I '7'. A FLOOD WAVE CREST (4600 ft. ElevatioM. 25 ft. Deep) V . ~ ___________________________________ '7'_~ ____________________ E _________ i
G~IJ .:r. t e r- n .:t. r' y G~ IJ .;t. t e r' n .;t. r' :'7" ----, ! -=...1 -------::?;v .. 1;""11 :-:"Ij ':"":'1.)~i -:-IJ:-:::rr:-, ------;l=;-~! l:-:-j -:-,~."T.t-:e-::::-::' f::-! -~:-:. r=--'- -:,.-LaKe Sediments (sand & gravel) LaKe Sedime~t~ 1 I ! I I 1 i j 12 I ~2 ':r 1 1 .:::- 0 1~1 1 1 .... 'J '-' ~, '7J .-:~
'-' i. ... ' PF.~OI..)O ,5 ,-, . .:, t7' !:::
1 C' E! ''') 2 R I ~.,.JER .j 2 I:' -=; '-' L. L. '-' 2 0 7 5 ( 1 ..•.. 1 i dth ~ fl?e t ) 5 J'~' ~)
DIAGRAMMATIC REPRESENTATION OF CROSS-SECTION #15: River Mi 1e=15.63
Scales: Horizontal=1:.11404, Vertical= 1:1426;Ver-tfcal ExaQQerat~on=8x
--= ..:' i :. ..;..
I o 1 Mile
Base from U.S. Geological Survey topographic quadrangles Aspen Grove and Bridal Veil Falls.
PLATE 1. INUNDATED AREA RESULTING FROM A
POSTULATED WORST-CASE SCENARIO DEER CREEK DAM
FAILURE, PROVO RIVER, UTAH
EXPLANATION
~ approximate limit of flooding
2 cross-section number
~
::c:
~ . ~
, ........
>4
~
o 1 Mile ~I--------------~I ..
. I
Baae from U.S. Geological Survey topograph ic quadrangles Crem and Provo.
PLATE 1: (continued) INUNDATED AREA RESUL TII\iG FROM A POSTULATED WORST-CASE SCENARIO DEER CREEK DAM FAILURE, PROVO RIVER, UTAH
EXPLANATION
.............. approximate limit of flooding
2 cr08l M section number