U.S. Department of the Interior

Bureau of Reclamation

Technical Service Center

Denver, Colorado September 2009

Technical Report No. SRH-2009-36

Clear Lake 

2007 Hydrographic Survey
ii
U.S. Department of the Interior

Bureau of Reclamation

Technical Service Center

Water and Environmental Resources Division

Sedimentation and River Hydraulics Group

Denver, Colorado September 2009

Technical Report No. SRH-2009-36

Clear Lake

2007 Hydrographic Survey

prepared by

Ronald L. Ferrari 
ACKNOWLEDGMENTS

Bureau of Reclamation's (Reclamation) Sedimentation and River Hydraulics 

(Sedimentation) Group of the Technical Service Center (TSC) prepared and 

published this report. Ronald Ferrari of the Sedimentation Group and Robert 

Woods (retired) of the Klamath Area Office of the Mid Pacific Region conducted 

the bathymetry survey of the reservoir in May 2007. The above water topography 

was collected by an aerial survey in October 2005 under the direction of Terri 

Reaves of the Mid Pacific Regional Office. Michael Neuman of Reclamation’s 

Klamath Area Office was the study coordinator. Ron Ferrari completed the data 

processing to generate the reservoir topography, surface areas, and resulting 2007 

area-capacity tables presented in this report. Kent Collins performed the technical 

peer review of this documentation.

Mission Statements

The mission of the Department of the Interior is to protect and 

provide access to our Nation’s natural and cultural heritage and 

honor our trust responsibilities to Indian Tribes and our 

commitments to island communities.

The mission of the Bureau of Reclamation is to manage, develop, 

and protect water and related resources in an environmentally and 

economically sound manner in the interest of the American public.

Reclamation Report

This report was produced by the Bureau of Reclamation’s Sedimentation and 

River Hydraulics Group (Mail Code 86-68240), PO Box 25007, Denver, 

Colorado 80225-0007, www.usbr.gov/pmts/sediment/. 

Disclaimer

No warranty is expressed or implied regarding the usefulness or completeness of 

the information contained in this report. References to commercial products do 

not imply endorsement by the Bureau of Reclamation and may not be used for 

advertising or promotional purposes.
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PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 

1. REPORT DATE (DD-MM-YYYY) 

September 2009

2. REPORT TYPE 3. DATES COVERED (From – To)

4. TITLE AND SUBTITLE 

Clear Lake

2007 Hydrographic Survey

5a. CONTRACT NUMBER

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S) 

Ronald L. Ferrari

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 

Bureau of Reclamation, Technical Service Center, Denver, CO 80225

8. PERFORMING ORGANIZATION REPORT 

NUMBER 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 

Bureau of Reclamation, Denver Federal Center, PO Box 25007

Denver, CO 80225-0007

10. SPONSOR/MONITOR'S ACRONYM(S)

11. SPONSOR/MONITOR'S REPORT 

NUMBER(S) 

12. DISTRIBUTION/AVAILABILITY STATEMENT 

13. SUPPLEMENTARY NOTES 

14. ABSTRACT

Reclamation surveyed Clear Lake in May 2007 to develop updated reservoir topography and compute the present storageelevation relationships. The underwater survey was conducted near water surface elevation 4,528.5 feet (project datum) or 

4,472.0 feet in North American Vertical Datum of 1988 (NAVD88). The underwater survey used sonic depth recording 

equipment interfaced with a real-time kinematic (RTK) global positioning system (GPS) that provided continuous sounding 

positions throughout the underwater portion of the reservoir covered by the survey vessel. The total reservoir topography was 

determined by importing digital contour data from a regional aerial survey conducted on October 24, 2005 near water surface 

elevation 4,522 (project datum) or 4,465.5 feet (NAVD88). The developed topography elevations presented in this report are

tied to NAVD88. The computed area and capacity information presented in this report is tied to the project vertical datum,

measured during the 2007 survey as 56.5 feet greater than NAVD88.

As of May 2007, at reservoir water surface elevation 4,543.0 feet (spillway crest), the surface area was 25,344 acres with a total 

capacity of 507,252 acre-feet.

15. SUBJECT TERMS 

reservoir area and capacity/ sedimentation/ reservoir surveys/ global positioning system/ sounders/ contour 

area/ RTK GPS/ 

16. SECURITY CLASSIFICATION OF: 17. LIMITATION 

OF ABSTRACT

18. NUMBER 

OF PAGES 

19a. NAME OF RESPONSIBLE PERSON

a. REPORT b. ABSTRACT a. THIS PAGE 19b. TELEPHONE NUMBER (Include area code)

Standard Form 298 (Rev. 8/98) 

Prescribed by ANSI Std. Z39.18 
Table of Contents

Page

i

Introduction ...................................................................................................................................... 1

Summary and Conclusions............................................................................................................... 4

Control Survey Data Information..................................................................................................... 4

Hydrographic Survey Equipment and Method ................................................................................. 6

2007 Topography Development.............................................................................................. 11

2007 Storage Capacity ............................................................................................................ 31

2007 Analyses of Results........................................................................................................ 39

References...................................................................................................................................... 39

Appendix ........................................................................................................................................ 41

Index of Figures

Page

Figure 1 - Bureau of Reclamation reservoirs in Northern California. .............................................. 1

Figure 2 - Clear Lake Reservoir....................................................................................................... 2

Figure 3 - California White Pelican on an island formed by Clear Lake, May 2007. ...................... 2

Figure 4 - Clear Lake Dikes. ............................................................................................................ 3

Figure 5 - BOR benchmark established for the 2007 bathymetric survey, east bank....................... 5

Figure 6 - Survey vessel with mounted instrumentation used for the Clear Lake survey. ............... 6

Figure 7 - Bathymetric instrumentation used for the 2007 survey. .................................................. 7

Figure 8 - Clear Lake Bathymetric Data Points, May 2007. ............................................................ 9

Figure 9 - Clear Lake fully developed TIN. ................................................................................... 13

Figure 10 - Clear Lake TIN of the dam area. Dark outside line is top of parapet wall, elevation

4,491.5 (NAVD88). .............................................................................................................. 15

Figure 11 – Clear Lake contours at the dam, all elevations in NAVD88. Outside boundary 

elevation 4,491.5, top of parapet wall. Dash line is dam elevation 4,487.5 (NAVD88). 

Contours presented at 1 and 2-foot increments..................................................................... 19

Figure 12 – Clear Lake contours. ................................................................................................... 21

Figure 13 – Clear Lake contours, east area of the reservoir. .......................................................... 23

Figure 14 – Clear Lake contours, west area of the reservoir, (NAV88)......................................... 25

Figure 15 - Clear Lake 1-foot contours from elevation 4,465 (NAVD88) and below.................... 27

Figure 16 - Clear Lake aerial photo, October 2005 near reservoir elevation 4,465.5 (NAVD88), 

project elevation 4,522. Area of the narrows between east and west water bodies.............. 29

Figure 17 – Clear Lake area and capacity plots.............................................................................. 35

Index of Tables

Page

Table 1 - Reservoir sediment data summary (page 1 of 2)............................................................. 33

Table 2 - Summary of 2007 survey results..................................................................................... 37

Appendix
1

Clear Lake

2007 Hydrographic Survey

Introduction

Clear Lake Dam and reservoir, located on the Lost River in Modoc County, 

California, is 39 miles southeast of Klamath Falls, Oregon, Figures 1 and 2. Clear 

Lake, part of the Klamath Project, provides irrigation storage, reduced flows into 

the reclaimed portion of Tule Lake, and flood control benefits to the towns of 

Tule Lake, Marline, Olene, and Merrill, Oregon. The reservoir, part of a National 

Wildlife Refuge, provides habitat for the endangered Lost River and Short Nose 

Suckers along with nesting areas for such birds as the California White Pelican, 

Figure 3. Clear Lake was a natural lake that was enlarged by the dam and 

occupies a flat alluvial basin in a barren volcanic terrain. The total drainage area 

above Clear Lake is 735 square miles.

Figure 1 - Bureau of Reclamation reservoirs in Northern California.
2

Figure 2 - Clear Lake Reservoir

Figure 3 - California White Pelicans on an island formed by Clear Lake, May 2007.
3

The original dam, completed in 1910, was an earthen structure. Due to 

deterioration, the original dam was replaced in 2002 by a concrete dam near the 

old alignment. The new dam has a crest elevation of 4,544.0 feet1, a four foot 

parapet wall with top elevation 4,548.0, and a spillway with a crest elevation of 

4,543.0. There is a small hydroelectric plant at the dam with a capacity of three 

megawatts. The dam is owned by Reclamation and operated by the Langell 

Valley Irrigation District.

The reservoir content is impounded by the dam on the north end and two earthcore, rip-rap protected dikes located in the shallow saddles at the south end of the 

reservoir. A 2005 aerial survey indicates the two interconnected dikes contain the 

reservoir body from water surface elevation 4536.5 up to the top of parapet wall 

elevation, 4,548.0 (Figure 4). The main dike was constructed in the late 1930’s

and runs east-west. The south dike runs in a northwest-southeast direction and 

was constructed in 1974.

Figure 4 - Clear Lake Dikes.

 

1Elevations are shown in feet. Unless noted, all elevations in this report are based on the original project 

datum established by Reclamation that is around 60.1 feet higher than the National Geodetic Vertical Datum 

of 1929 (NGVD29) and 56.5 feet higher than the North American Vertical Datum of 1988 (NAVD88).
4

Summary and Conclusions

This Reclamation report presents the results of the 2007 survey of Clear Lake 

with the primary objectives to develop current reservoir topography and areacapacity relationships. The bathymetric survey was conducted using sonic depth 

recording equipment interfaced with a real-time kinematic (RTK) global 

positioning system (GPS) that provided continuous sounding positions throughout 

the underwater portion of the reservoir covered by the survey vessel. The system 

continuously recorded depth and horizontal coordinates of the survey boat as it 

navigated along previously established sediment range lines. The positioning 

system provided information that allowed the boat operator to maintain a course 

along these grid lines. Data were also collected as the boat traversed along the 

shoreline between profile lines. Water surface elevations recorded by a 

Reclamation gage during the time of collection were used to convert the sonic 

depth measurements to reservoir bottom elevations on the project datum. During 

collection, the water surface was also recorded using the RTK GPS collection 

system. The above water topography was developed by a regional aerial survey 

conducted on October 24, 2005 near water surface elevation 4,522.0.

Tables 1 and 2 contain the summary of the 2007 Clear Lake survey results. The 

2007 survey determined that the reservoir had a total storage capacity of 507,252

acre-feet and a surface area of 25,344 acres at reservoir spillway crest elevation 

4,543.0. The 2007 area and capacity tables were produced by a computer 

program that uses measured contour surface areas and a curve-fitting technique to 

compute the area and capacity at prescribed elevation increments (Bureau of 

Reclamation, 1985). The Clear Lake area and capacity tables, at elevation 

increments 0.1 feet, are presented in the appendix.

Control Survey Data Information

During the 2007 bathymetric survey no known datum points, tied to 2005 aerial 

control network, were located near the reservoir. A control survey was conducted 

for the bathymetric survey using the on-line positioning user service (OPUS) and 

RTK GPS measurements to establish a horizontal and vertical control network 

near the reservoir. OPUS is operated by the National Geodetic Survey (NGS) and 

allows users to submit raw GPS data files that are processed with known point 

data to determine positions relative to the national control network. A GPS base 

was set over two bench marks established for the bathymetric survey with one 

located near the dam on the north bank and another located on the west bank of 

the reservoir, Figure 5. The coordinates for these points were computed using 

OPUS, and from these base locations additional features were measured including 
5

daily water surfaces, road alignment over the dam, and a Reclamation monument 

located near the dam with a published project elevation of 4,549.14. The OPUS 

processed coordinates measured at this location were:

California Zone 1, NAD83, NAVD88 (feet)

North 2,586,444.528

East 6,812,931.054

Elevation 4,492.661

The horizontal control was established in California state plane coordinates, zone

1, on the North American Datum of 1983 (NAD83). The vertical control for the

established points was tied to NAVD88. RTK GPS water surface measurements 

were periodically collected and a comparison to the reservoir water surface 

recorded by the Reclamation gage found the NAVD88 vertical elevation 

measurements were around 56.5 feet lower than the recorded project elevations. 

The same vertical difference was found when comparing the RTK GPS measured 

elevation on the Reclamation bench mark. NGS published data in the study area 

shows the NAVD88 elevations are around 3.5 feet higher than NGVD29.

Figure 5 - BOR benchmark established for the 2007 bathymetric survey, east bank.
6

Hydrographic Survey Equipment and

Method

The hydrographic survey equipment was mounted on a small, flat bottom, open,

aluminum vessel equipped with an outboard motor, Figures 6 and 7. Originally it 

was proposed to use the Sedimentation Group’s larger survey vessel in October 

2006, but the low lake levels that persisted through May 2007 raised concerns 

about launching the vessel and getting it back on the trailer. The hydrographic 

system included a GPS receiver with a built-in radio, a depth sounder, a 

helmsman display for navigation, a laptop computer, hydrographic system 

software for collecting the underwater data, and 12-volt battery that powered the 

equipment. The shore equipment included a second GPS receiver with an 

external radio. The shore GPS receiver and antenna were mounted on a survey 

tripod over the known datum points. A 12-volt battery provided the power for the 

shore unit.

The Sedimentation Group uses RTK GPS with the major benefit being precise 

heights measured in real time to monitor water surface elevation changes. The 

basic output from a RTK receiver are precise 3-D coordinates in latitude, 

longitude, and height with accuracies on the order of 2 centimeters horizontally 

and 3 centimeters vertically. The output is on the GPS datum of WGS-84 that the 

hydrographic collection software converted into California’s state plane

Figure 6 - Survey vessel with mounted instrumentation used for the Clear Lake survey.
7

Figure 7 - Bathymetric instrumentation used for the 2007 survey.

coordinates, zone 1, in NAD83. The RTK GPS system employs two receivers 

that track the same satellites simultaneously just like with differential GPS.

The Clear Lake bathymetric survey was conducted in 2007 from May 3 through 

May 17 between water surface elevations 4,528.3 and 4,528.5 (project datum). 

During post processing, the bathymetric depths were converted to bottom 

elevations in NAVD88 by shifting the Reclamation measured water surface gage

elevations by 56.5 feet, then subtracting the depths from the shifted elevations. 

The bathymetric survey was conducted using sonic depth recording equipment, 

interfaced with a RTK GPS, capable of determining sounding locations within the 

reservoir. The survey system software continuously recorded reservoir depths 

and horizontal coordinates as the survey boat navigated along the range lines and 

also while the boat traveled between range lines. A low water contour developed 

from the aerial survey, elevation 4,522.5, was used to determine the boundary for 

bathymetric data collection and once the boat crossed that contour, it was 

maneuvered to the next survey line while continuously collecting data. The 

survey vessel's guidance system provided directions to the boat operator to assist 

in maintaining the course along these predetermined lines. A layout of the survey 

vessels collection path is shown on Figure 8.
8

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9

Figure 8 - Clear Lake Bathymetric Data Points, May 2007.
10

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11

The underwater data was collected by a depth sounder calibrated using a survey 

rod that measured the water depth below the transducer at different locations and 

times during the survey period. The sounder’s digital depths were matched to the 

rod readings by adjusting the speed of sound through the water column, which can 

vary with density, salinity, temperature, turbidity, and other conditions. There 

were different locations on the reservoir, such as the deeper, western reservoir 

areas, where the survey rod could be pushed into the soft reservoir bottom from 

one-half to over one foot. These areas were located in the deepest portions of the 

reservoir where the “natural” lake existed prior to the dam. For calibration of the 

sounder, the depth used was where the survey rod settled on the reservoir bottom 

using little pressure to hold it in place. The collected data were digitally 

transmitted to the computer collection system through a RS-232 port. The depth 

sounder also produced an analog hard-copy chart of the measured depths. These 

graphed analog charts were analyzed during post processing, and when the analog 

charted depths indicated a difference from the computer recorded bottom depths, 

the computer data files were modified. Additional information on collection and 

analysis procedures are outlined in Chapter 9 of the Erosion and Sedimentation 

Manual (Ferrari and Collins, 2006).

The upper portion of the reservoir, not covered by the 2007 boat survey, was 

developed from an aerial survey conducted on October 24, 2005 near reservoir 

water surface elevation 4,466 (NAVD88), project elevation 4,522.5. As 

previously stated, this study developed the reservoir topography with the vertical 

elevations tied to NAVD88. The aerial data was tied to NAVD88 and having the 

same vertical datum for the aerial and bathymetric data allows it to be more easily 

distributed and used by others. During post processing, the developed area and 

capacity information presented in this report was tied to the Reclamation vertical 

datum by shifting the NAVD88 topographic data upward by 56.5 feet. The 

horizontal network is in California, zone 1, NAD83.

2007 Topography Development

The topography of Clear Lake was developed from the 2005 aerial data and the 

2007 bathymetric survey data sets. All elevations presented on the following 

drawings are tied to NAVD88, which is 56.5 feet lower than the Clear Lake 

project datum. This means the top of the dam is 4,544.0 feet in project elevation 

and 4,487.5 feet in NAVD88 elevation.

The detailed aerial reservoir data layers were provided in digital format by 

Reclamation’s Mid-Pacific Regional Office. The digital aerial data included the 

smooth contours, the developed breaklines, and point data that were used to 

develop the reservoir information for this study. The aerial data extended beyond 

the maximum height of the reservoir (elevation 4,548.0 - top of the parapet wall)

and the size of these aerial data files was reduced by removing data points above 

elevation 4,520 (NAVD88) to make them more manageable. This point filtering, 
12

allowed development of a single Triangulated Irregular Network (TIN) over the 

entire reservoir to compute surface areas, volumes, and contours.

A TIN is a set of adjacent non-overlapping triangles computed from irregularly 

spaced points with x,y coordinates and z values. A TIN is designed to deal with 

continuous data such as elevations. The TIN software uses a method known as 

Delaunay's criteria for triangulation where triangles are formed among all data 

points within the polygon clip. The method requires that a circle drawn through 

the three nodes of a triangle will contain no other point, meaning that all the data 

points are connected to their nearest neighbors to form triangles. This method 

preserves all the collected data points. The TIN method is described in more 

detail in the ARCGIS user’s documentation, (ESRI, 2009).

The first TIN was developed using the aerial data sets as listed above along with 

the bathymetric data sets. From this TIN, one foot contours were developed 

starting at elevation 4,454.0 and extending beyond elevation 4,600.0 (NAVD88). 

These contours extended outside the reservoir area going downstream of the dam 

and dikes that enclose the water body. To force contour development only within 

the reservoir area, a hardclip contour was selected that ran around the entire 

reservoir and along the dam and dike alignment. Contour elevation 4,493.0 

(NAVD88) was selected as the hard boundary for the 2007 developed contours,

surface areas, and volumes. This boundary allowed mapping within the reservoir 

area as outlined by the hardclip polygon. Figures 9 and 10 are illustrations of the 

developed TIN of the reservoir. 
13

Figure 9- Clear Lake fully developed TIN.
14

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15

 

 Figure 10 - Clear Lake TIN of the dam area. Dark outside line is top of parapet wall, elevation 4,491.5 (NAVD88). 
16

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17

The linear interpolation option of the ARCGIS TIN and CONTOUR commands was

used to interpolate contours from the Clear Lake TIN. The contours were developed 

from the TIN at one- and two-foot increments from elevations 4,454.0 through

4,492.0 (NAVD88) and are presented in Figures 11 through 15. ARCGIS develops

contours directly from the TIN using all the enclosed data points, resulting in a 

jagged representation of some contours for this study. The jagged contours appear 

mainly in the deeper flatter portions of the reservoir mapped during the bathymetric 

survey. During the 2007 survey, bathymetric data was collected primarily along 

cross sections, resulting in extremely jagged developed contours in the flatter areas

of the reservoir as ARCMAP used all the data points which were of similar 

elevation. For presentation purposes, the contour lines were smoothed by removing 

the individual contour polygons containing minimal areas and using the smooth line 

option within ARCMAP. Additional hand editing was also completed for the lower 

bathymetric developed contours from elevation 4,455.0 through 4,465.0 (NAVD88). 

When using the extreme settings of the smooth line method, within ARCMAP, the 

contours tended to cross. Due to the crossing contours, extensive manually editing 

was used to develop the final contours presented on the maps in this report. The 

smoothing processes did not affect the reported surface areas of the topography since 

the surface areas were computed directly from the TIN using all the data points.

Figures 11 through 15 present the developed 1 and 2-foot contours with the 

elevations tied to NAVD88. The horizontal control is in California zone 1 state 

plane coordinates in NAD83. For presentation purposes the smooth aerial developed 

contours at 2-foot increments from elevation 4,466.0 through 4,486.0 (NAVD88) are 

illustrated. The dash line is elevation 4,487.5 (NAVD88) which represents the dam 

crest developed contour, project elevation 4,544.0. The upper solid line is elevation 

4,491.5 (NAVD88) which represents the top of parapet wall, project elevation

4,548.0. To show the details through the narrows along with the two large water 

bodies in the east and west side of the reservoir, one-foot contours were developed 

and plotted from elevation 4,466.0 and below.

The developed contours show for the east large reservoir body, near the dam, the 

deepest pool elevation is around elevation 4,464.0 (NAVD88), project elevation

4,420.5. The deepest pool elevation of the west large reservoir body is around

elevation 4,458.0 (NAVD88), project elevation 4,514.5. A “natural” lake existed in 

the west reservoir area prior to dam construction. Through the narrows that connects 

the two water bodies, there are some deep smaller pools developed from the 2007 

bathymetric data. It appears at reservoir elevation 4,465.0 (NAVD88), project 

elevation 4,521.5, there is a continuous connection between the two large water 

bodies. Figure 16 is an aerial photo of the narrows reach that was taken in October 

2005 near project elevation 4,522. The photo illustrates that there was a connection

between the two water bodies at elevation 4,522, but the murky water in the middle 

indicates that it may not be very deep. Since the 2007 bathymetric survey did not 

obtain a continuous thalweg through the narrow reach, additional data would need to 

be collected to verify the minimum reservoir elevation that allows flow between the 

east and west water bodies.

 
18

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19

Figure 11 – Clear Lake contours at the dam, all elevations in NAVD88. Outside boundary elevation 4491.5, top of parapet wall. Dash line, top of dam elevation 4487.5. Contours presented at 1 and 2-foot increments.
20

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21

Figure 12– Clear Lake contours.
22

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23

Figure 13 – Clear Lake contours, east area of the reservoir.
24

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25

Figure 14 – Clear Lake contours, west area of the reservoir, (NAV88).
26

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27

Figure 15 - Clear Lake 1-foot contours from elevation 4,465 (NAVD88) and below.
28

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29

Figure 16 - Clear Lake aerial photo, October 2005 near reservoir elevation 4,465.5 (NAVD88), project elevation 4,522. Area of the narrows between east and west water bodies.
30

 

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31

The 2007 surface areas for Clear Lake were computed at 1-foot increments 

directly from the reservoir developed TIN from elevation 4,454.0 (NAVD88)

through 4,492.0 (NAVD88), project elevation 4,510.5 through 4,548.5. The TIN 

was developed from the collected data sets within the hard clip polygon where the 

dam and dikes enclosed the water body. Surface area calculations were 

performed using ARCGIS commands that compute areas at user-specified 

elevations directly from the TIN using all the data points. For the purpose of this 

study, the ARCMAP computed survey areas at 1-foot increments were shifted to 

the project vertical datum by increasing the elevations by 56.5 feet. The resulting 

surface areas versus elevation were input into the ACAP program (Reclamation, 

1985) for computing the resulting Clear Lake 2007 area and capacity tables listed 

in the appendix.

2007 Storage Capacity

The storage-elevation relationships for Clear Lake, based on the measured surface 

areas, were generated in the area-capacity program ACAP using the least squares 

method of curve fitting. The ACAP program computes the surface area at 1.0-, 

0.1-, and 0.01-foot increments by linear interpolation between basic data contours. 

The respective capacities and capacity equations are then obtained by integration 

of the area equations. The initial capacity equation is tested over successive 

intervals to check whether it fits within an allowable error term (set at 0.000001 

for Clear Lake). The capacity equation is then used over the full range of 

intervals fitting within the allowable error limit. For the first interval at which the 

initial allowable error limit is exceeded, a new capacity equation (integrated from 

basic area curve over that interval) is utilized until it exceeds the error limit. 

Thus, the capacity curve is defined by a series of curves, each fitting a certain 

region of data. Differentiating the capacity equations, which are of second order 

polynomial form, the final capacity equations are derived:

y = a1 + a2x + a3x

2

where: y = capacity

x = elevation above a reference base

a1 = intercept

a2 and a3 = coefficients

Results of the 2007 Clear Lake area and capacity computations were developed

for 0.1-foot increments and are presented in the appendix of this report. A 

description of the computations and coefficients output from the ACAP program 

is included with these tables. The area-capacity relationships from the original

survey and 2007 are listed on Table 2 and the area-capacity curves are plotted on 

Figure 17. As of May 2007, at reservoir water surface elevation 4,543.0 (spillway 

crest) the surface area was 25,344 acres with a total capacity of 507,252 acre-feet.
32

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33

1. 2. 3. STATE California

4. 5. Malin 6. COUNTY

7. ° 55 ' 3 2 " ° 4 ' 32 " 8. 19. SPILLWAY CREST EL

10. 11. 12. GROSS STORAGE 15.

CAPACITY, AC-FT

a.

2

b.

c.

d. 16.

e.

f.

g.

17. LENGTH OF RESERVOIR

18. TOTAL DRAINAGE AREA

19. NET SEDIMENT CONTRIBUTING AREA 23. MEAN ANNUAL RUNOFF

20. LENGTH MILES AVG. WIDTH MILES 24. MEAN ANNUAL INFLOW

21. 25. °F °F

26. DATE OF 27. 28. 29. 30. 31. C/I

26. DATE OF 35. 36.

26. DATE OF 37. 38.

26. DATE OF 39.AVG. DRY WT. 40. SED. DEP. TONS/MI.2

-YR 41. STORAGE LOSS, PCT. 42.SEDIMENT 

(#/FT3) b. TOTAL b. TOTAL TO INFLOW, PPM

TO DATE DATE a. PER. b. TOT.

43.

Modoc

RATIO AF/AF

1910

to

BEGAN

23,376

4544.0

14.

4543.00

ACRE-FEET

2007 DATE

STORAGE

TOP OF DAM ELEVATION

DATA SHEET NO.

Contour 1-ft

M

D

A TWP. 17N

OWNER

SEC

LAT 41

RESERVOIR SEDIMENT

DATA SUMMARY

Clear Lake

NAME OF RESERVOIR 1

SURFACE CAPACITY

Y

D

T

V

ANNUAL TEMP, MEAN °F RANGE

R

a. TOTAL b.

PERIOD CAPACITY LOSS, ACRE-FEET

AVG. ANN. c. /MI.2

-YR. TOTAL b.

TOTAL SEDIMENT DEPOSITS TO DATE, AF

TOTAL

WATER INFLOW TO DATE, AF

b. MEAN ANN. b. TOTAL

PERIOD WATER INFLOW, ACRE-FEET

c. a. 

BEGAN

DATE NORMAL

33.

OPERATIONS

1910

32.

ACRE - FEET

507,252

MEAN ANNUAL PRECIPITATION

45

347,108

48,360

507,252

370,484

2007

25,344 136,768

SURFACE AREA, AC-FT

13.

E FLOOD CONTROL

R

E

S

48,360

DEAD

INACTIVE

4,536.4

4,521.0 12,237

298,748

R

V

MULTIPLE USE

23,198

R

O

I

23,547

U

N

S SURVEY

SQUARE MILES

735 SQUARE MILES

MILES AVG. WIDTH OF RESERVOIR

I MAX. ELEVATION

4,543.0

JOINT USE 4,537.4

CONSERVATION

S

A

B

RANGE

Bureau of Reclamation STREAM

8

Lost River

NEAREST P.O.

TOP OF POOL

8E

ACRE-FEET

INCHES

INCHES

MILES

INTERVALS

AREA, AC.

MAX. ANN.

44. REACH DESIGNATION PERCENT OF TOTAL ORIGINAL LENGTH OF RESERVOIR

DEPTH DESIGNATION ELEVATION RANGE IN FEET

DATE

SURVEY

26.

0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-100 110- 115- 120-

LONG 121

SURCHARGE

STORAGE

ALLOCATION

ELEVATION

SURVEY ANNUAL

34. PERIOD

TYPE OF 

MIN. ELEVATION

NO. OF

a.

PRECIPITATION

MEAN ANN.

27.5

25,344

RANGES OR 

YRS

PER. PER.

YRS

SURVEY

May 2007

SURVEY

SURVEY

26.

DATE

OF

a.

105-

E

A

A

 /MI.2 AVG. ANN. c. -YR.

PERIOD a. AVG. ANNUAL

a.

PERCENT OF TOTAL SEDIMENT LOCATED WITHIN REACH DESIGNATION

PERCENT OF TOTAL SEDIMENT LOCATED WITHIN DEPTH DESIGNATION

Table 1 - Reservoir sediment data summary (page 1 of 2).
34

1

2

584,735 4,548.0 26,863 637,905

4,542.0 24,992 482,084 4,544.0 25,669 532,760

0

5,731

24,337 432,756

4,510.0

ELEVATION AREA CAPACITY

4,514.0 7 14

4,546.0

0

19,690

22,408

26,290

4,534.0

4,528.0

4,540.0

Original dam, completed in 1910, was replaced in 2002 with a new dam with a lower crest elevation of 4,544.0 (project elevation). There 

47. REMARKS AND REFERENCES

 is a 4-foot parapet wall with top elevation 4,548.0. All elevations are project vertical datum that is 56.5 feet higher than NAVD88.0

49. Bureau of Reclamation September 2009

AGENCY MAKING SURVEY

AGENCY SUPPLYING DATA DATE

48.

4,516.0

YEAR MAX. ELEV. MIN. ELEV. INFLOW, AF

Bureau of Reclamation

 All storage allocation values are computed using the 2007 area and capacity tables.

MIN. ELEV. INFLOW, AF YEAR MAX. ELEV.

165,172

292,386

46. ELEVATION - AREA - CAPACITY - DATA FOR

4,518.0 8,349 21,114

248,262

384,669

127,108

4,520.0 8,929 38,431

ELEVATION

4,512.0 4 4

CAPACITY ELEVATION AREA CAPACITY

45. RANGE IN RESERVOIR OPERATION

6,510

AREA

4,530.0 20,792 205,749 21,688

23,058 337,857 4,538.0

61,651

4,536.0 23,739

4,532.0

4,522.0 14,286 4,524.0 16,381 92,312 4,526.0 18,296

Table 1 – Reservoir sediment data summary (page 2 of 2).
35

Area-Capacity Curves for Clear Lake

4,510.0

4,515.0

4,520.0

4,525.0

4,530.0

4,535.0

4,540.0

4,545.0

4,550.0

0 65000 130000 195000 260000 325000 390000 455000 520000 585000 650000

Capacity (acre-feet) Elevation (feet)

4,510.0

4,515.0

4,520.0

4,525.0

4,530.0

4,535.0

4,540.0

4,545.0

4,550.0

27,000 24,300 21,600 18,900 16,200 13,500 10,800 8,100 5,400 2,700 0

2007 Survey

Original Survey

Area

Capacity

Area (acre) Figure 17 – Clear Lake area and capacity plots.
36

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37

2007 2007

Elevations Original Original 2007 2007 Volume Percent of

Survey Capacity Survey Survey Difference Difference

(feet) (acres) (acre-feet) (acres) (acre-feet) 

1

4,548.0 26,863 637,905

4,547.0 26,591 611,176

4,546.0 26,290 584,735

4,545.0 25,996 558,592

2

4,544.0 25,669 532,760

3

4,543.0 25,760 518,510 25,344 507,252 11,258 100

4,542.0 25,440 492,910 24,992 482,084 10,826 96

4,541.0 25,120 467,630 24,667 457,255 10,375 92

4,540.0 24,800 442,670 24,337 432,756 9,914 88

4,539.0 24,480 418,030 24,050 408,563 9,467 84

4,538.5 24,320 405,830 23,894 396,577 9,253 82

4,538.0 24,160 393,710 23,738 384,669 9,041 80

4,537.0 23,840 369,710 23,412 361,091 8,619 77

4,536.0 23,520 346,030 23,058 337,857 8,173 73

4,535.0 23,200 322,670 22,740 314,957 7,713 69

4,534.0 22,790 299,675 22,408 292,386 7,289 65

4,533.0 22,380 277,090 22,075 270,145 6,945 62

4,532.0 21,970 254,915 21,688 248,262 6,653 59

4,531.0 21,560 233,150 21,276 226,780 6,370 57

4,530.0 21,150 211,795 20,792 205,749 6,046 54

4,529.0 20,540 190,950 20,317 185,186 5,764 51

4,528.0 19,930 170,715 19,690 165,172 5,543 49

4,527.0 19,320 151,090 19,055 145,795 5,295 47

4,526.0 18,710 132,075 18,296 127,108 4,967 44

4,525.0 18,100 113,670 17,458 109,223 4,447 40

4,524.0 16,260 96,490 16,381 92,312 4,178 37

4,523.0 14,420 81,150 15,313 76,477 4,673 42

4,522.0 12,580 67,650 14,286 61,651 5,999 53

4,521.0 10,740 55,990 12,237 48,360 7,630 68

4,520.0 8,900 46,170 8,929 38,431 7,739 69

4,519.0 8,491 37,475 8,673 29,631 7,844 70

4,518.0 8,082 29,188 8,348 21,114 8,074 72

4,517.0 7,673 21,311 7,873 12,984 8,327 74

4,516.0 7,264 13,843 6,510 5,731 8,112 72

4,515.0 6,800 6,800 2,823 863 5,937 53

4,514.0 3,400 1,700 7 14 1,686 15

4,513.5 1,700 425 6 11 414 4

4,513.0 0 0 5 8 -8 0

4,510.0 0.0 0.0 0.0 0.0 0.0 0

1

Top of Parapet Wall

2 Dam crest

3 Spillway crest

Table 2 - Summary of 2007 survey results.
38

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39

2007 Analyses of Results

The Clear Lake original and 2007 area and capacity values are illustrated on 

Figure 17 and listed on Tables 1 and 2. These presentations illustrate the capacity 

differences from the two different surveys and show very little change, 11,258

acre-feet below the survey crest (project elevation 4,543.0). This change maybe 

primarily due to the accuracy differences between the two methods of collection 

since it is assumed the 2005 aerial survey provided much better detail of the 

actual reservoir topography than any previous collection. The area and capacity 

comparison plots provide a good illustration of how minor the changes are for the 

different elevation zones. The results from the 2007 survey present the current 

area and capacity of the reservoir along with the digitally developed topography 

of the reservoir bottom.

References

American Society of Civil Engineers, 1962. Nomenclature for Hydraulics, ASCE 

Headquarters, New York.

Bureau of Reclamation, 1981. Project Data, Denver Office, Denver CO.

Bureau of Reclamation, 1985. Surface Water Branch, ACAP85 User's Manual, 

Technical Service Center, Denver CO.

Bureau of Reclamation, 1987(a). Guide for Preparation of Standing Operating 

Procedures for Bureau of Reclamation Dams and Reservoirs, U.S. Government 

Printing Office, Denver, CO.

Bureau of Reclamation, 1987(b). Design of Small Dams, U.S. Government 

Printing Office, Denver CO.

Bureau of Reclamation, January 2006. Standing Operating Procedures (SOP), 

Clear Lake Dam and Reservoir, Klamath Falls Project, Mid-Pacific Region, 

Sacramento, California.

ESRI, 2009. Environmental Systems Research Institute, Inc. (www.esri.com)

Ferrari, R.L. and Collins, K. (2006). Reservoir Survey and Data Analysis, 

Chapter 9, Erosion and Sedimentation Manual, Bureau of Reclamation, 

Sedimentation and River Hydraulics Group. Denver, Colorado.

www.usbr.gov/pmts/sediment
40

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41

Appendix
42

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43

UNTIED STATES

DEPARTMENT OF THE INTERIOR

BUREAU OF RECLAMATION

MID PACIFIC REGION

KLAMATH FALLS PROJECT

CLEAR LAKE

CALIFORNIA

AREA AND CAPACITY TABLES

MAY 2007
44

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45

Clear Lake tables were generated by means of the area-capacity program ACAP, using the least squares 

method of curve fitting developed by Reclamation’s Technical Service Center. This program computes area 

at 1.0-, 0.1-, and 0.01-foot increments by linear interpolation between provide data. The capacity 

equations are obtained by integration of the area equations. The initial capacity equation is tested over 

successive intervals to check if it fits within an allowable error term. At the next interval beyond, a 

new capacity equation (integrated from the basic area equation over that interval) begins testing the fit 

until it exceeds the error term. The capacity curve becomes a series of curves, each fitting a certain 

region of data. The final area equations are obtained by differentiation of the capacity equations. 

Capacity equations are of the form y = a1 + a2x +a3x

2 where y is capacity and x is the elevation above an 

elevation base. The capacity equation coefficients for the reservoir are shown below (ε = 0.000001).

 CLEAR LAKE 2007 SURVEY 

 AREA-CAPACITY TABLES (BOR VERTICAL DATUM) 

EQUATION ELEVATION CAPACITY COEFFICIENT COEFFICIENT COEFFICIENT

 NUMBER BASE BASE A1(INTERCEPT) A2(1ST TERM ) A3(2ND TERM )

 1 4510.00 0 0.0000 0.0000 0.9000

 2 4514.00 14 14.4000 7.2000 275.4000

 3 4514.50 86 86.8500 282.6001 2540.7996

 4 4515.00 863 863.3500 2823.3996 2245.2008

 5 4515.50 2836 2836.3501 5068.6003 1441.0984

 6 4516.00 5730 5730.9247 6509.6994 804.0039

 7 4516.50 9186 9186.7753 7313.7009 559.3994

 8 4517.00 12983 12983.4757 7873.1007 276.0986

 9 4517.50 16989 16989.0505 8149.2008 199.3024

 10 4518.00 21113 21113.4765 8348.4990 175.6034

 11 4518.50 25331 25331.6270 8524.0984 149.0060

 12 4519.00 29630 29630.9263 8673.1134 125.3767

 13 4519.50 33998 33998.8281 8798.5155 130.4687

 14 4520.00 38430 38430.7023 8929.0130 346.7773

 15 4520.50 42981 42981.9021 9275.8048 2961.5931

 16 4521.00 48360 48360.2035 12237.4098 1081.6755

 17 4521.50 54749 54749.3285 13319.0895 967.2223

 18 4522.00 61650 61650.6797 14286.3179 566.4620

 19 4522.50 68935 68935.4540 14852.7886 460.2260

 20 4523.00 76476 76476.9057 15313.0059 509.1797

 21 4523.50 84260 84260.7045 15822.1942 558.9146

 22 4524.00 92311 92311.5315 16381.0971 521.8052

 23 4524.50 100632 100632.5321 16902.8957 555.2037

 24 4525.00 109222 109222.7810 17458.0977 435.6166

 25 4525.50 118060 118060.6552 17894.7287 401.6645

 26 4526.50 136356 136356.9693 18696.9802 358.3426

 27 4527.00 145795 145795.0485 19055.2916 326.0324

 28 4527.50 155404 155404.2037 19381.2971 309.0123

 29 4528.00 165172 165172.1105 19690.3156 333.9844

 30 4528.50 175100 175100.7679 20024.2832 292.2991

 31 4529.00 185185 185185.9866 20316.5689 255.4687

 32 4529.50 195408 195408.1429 20571.9908 220.3125

 33 4530.00 205749 205749.2210 20792.2720 235.9375

 34 4530.50 216204 216204.3454 21028.1554 247.7958

 35 4531.00 226780 226780.3300 21276.4759 205.6090

 36 4532.00 248262 248262.1788 21689.6564 192.7921

 37 4533.00 270144 270144.2021 22075.7401 166.2624

 38 4534.00 292385 292386.1560 22402.9083 168.3129

 39 4535.00 314957 314957.5815 22741.6295 157.9582

 40 4536.00 337857 337857.4757 23054.2296 179.0428

 41 4537.00 361091 361090.8584 23418.3575 160.2018

 42 4538.00 384669 384669.1305 23738.0844 155.8129

 43 4539.00 408562 408562.8826 24048.3634 144.3692

 44 4540.00 432755 432756.0007 24331.4054 167.7718

 45 4541.50 469630 469630.5839 24823.1694 169.0632

 46 4542.50 494623 494622.8217 25172.4744 171.0082

 47 4543.50 519965 519966.1597 25505.7792 163.3868

 48 4545.00 558592 558592.7358 25994.4792 147.5632

 49 4546.50 597916 597916.5979 26446.6708 144.0049

 50 4547.50 624506 624506.9865 26729.3659 134.0770

The Clear Lake survey in May 2007 used the contour method to obtain the basic data for these tables. 

Close interval profiles of the underwater portion of the reservoir were collected by standard 

surveying techniques using a global positioning system and echo sounder. The above-water portion was 

developed from aerial photography obtained in October of 2005. The computed surface areas from these 

surveys provided measured surface areas 0.5-foot increments from elevation 4,510 to 4,548.5. All data 

for these tables are tied to the project vertical datum that is 56.5 feet greater than the North 

American Vertical Datum of 1988.
46

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47

 CLEAR LAKE 2007 SURVEY

 AREA -CAPACITY TABLES (BOR VERTICAL DATUM, FEET)

AREA TABLE IN ACRES

Elevation 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

4510 0 0 0 1 1 1 1 1 1 2

4511 2 2 2 2 3 3 3 3 3 3

4512 4 4 4 4 4 5 5 5 5 5

4513 5 6 6 6 6 6 7 7 7 7

4514 7 62 117 172 228 283 791 1,299 1,807 2,315

4515 2,823 3,272 3,722 4,171 4,620 5,069 5,357 5,645 5,933 6,222

4516 6,510 6,671 6,831 6,992 7,153 7,314 7,426 7,538 7,649 7,761

4517 7,873 7,928 7,984 8,039 8,094 8,149 8,189 8,229 8,269 8,309

4518 8,349 8,384 8,419 8,454 8,489 8,524 8,554 8,584 8,614 8,643

4519 8,673 8,698 8,723 8,748 8,773 8,799 8,825 8,851 8,877 8,903

4520 8,929 8,998 9,068 9,137 9,206 9,276 9,868 10,460 11,053 11,645

4521 12,237 12,454 12,670 12,886 13,103 13,319 13,513 13,706 13,899 14,093

4522 14,286 14,400 14,513 14,626 14,740 14,853 14,945 15,037 15,129 15,221

4523 15,313 15,415 15,517 15,619 15,720 15,822 15,934 16,046 16,158 16,269

4524 16,381 16,486 16,590 16,694 16,799 16,903 17,014 17,125 17,236 17,347

4525 17,458 17,545 17,632 17,720 17,807 17,894 17,975 18,055 18,136 18,216

4526 18,296 18,377 18,457 18,537 18,618 18,698 18,769 18,840 18,912 18,984

4527 19,055 19,121 19,186 19,251 19,316 19,381 19,443 19,505 19,567 19,629

4528 19,690 19,757 19,824 19,891 19,958 20,024 20,083 20,141 20,200 20,258

4529 20,317 20,368 20,419 20,470 20,521 20,572 20,616 20,660 20,704 20,748

4530 20,792 20,840 20,887 20,934 20,981 21,028 21,078 21,127 21,177 21,226

4531 21,276 21,318 21,359 21,400 21,441 21,482 21,523 21,564 21,605 21,647

4532 21,688 21,728 21,767 21,805 21,844 21,882 21,921 21,960 21,998 22,037

4533 22,075 22,109 22,142 22,176 22,209 22,242 22,275 22,309 22,342 22,375

4534 22,408 22,437 22,470 22,504 22,538 22,571 22,605 22,639 22,672 22,706
48

 CLEAR LAKE 2007 SURVEY

 AREA -CAPACITY TABLES (BOR VERTICAL DATUM, FEET)

AREA TABLE IN ACRES

Elevation 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

4535 22,740 22,773 22,805 22,836 22,868 22,900 22,931 22,963 22,994 23,026

4536 23,058 23,090 23,126 23,162 23,198 23,233 23,269 23,305 23,341 23,377

4537 23,412 23,450 23,482 23,515 23,547 23,579 23,611 23,643 23,675 23,707

4538 23,739 23,769 23,800 23,832 23,863 23,894 23,925 23,956 23,987 24,019

4539 24,050 24,077 24,106 24,135 24,164 24,193 24,222 24,251 24,279 24,308

4540 24,337 24,365 24,399 24,432 24,466 24,499 24,533 24,566 24,600 24,633

4541 24,667 24,701 24,734 24,768 24,801 24,835 24,857 24,891 24,925 24,958

4542 24,992 25,026 25,060 25,094 25,128 25,161 25,207 25,241 25,275 25,309

4543 25,344 25,378 25,412 25,446 25,480 25,515 25,539 25,571 25,604 25,637

4544 25,669 25,702 25,735 25,767 25,800 25,833 25,865 25,898 25,931 25,963

4545 25,996 26,024 26,054 26,083 26,113 26,142 26,172 26,201 26,231 26,260

4546 26,290 26,319 26,349 26,378 26,408 26,437 26,476 26,504 26,533 26,562

4547 26,591 26,620 26,648 26,677 26,706 26,735 26,756 26,783 26,810 26,837
49

 CLEAR LAKE 2007 SURVEY

 AREA -CAPACITY TABLES (BOR VERTICAL DATUM, FEET)

CAPACITY TABLE IN ACRE-FEET

Elevation 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

4510 0 0 0 0 0 0 0 0 1 1

4511 1 1 1 2 2 2 2 3 3 3

4512 4 4 4 5 5 6 6 7 7 8

4513 8 9 9 10 10 11 12 12 13 14

4514 14 18 27 41 61 87 141 245 400 606

4515 863 1,168 1,518 1,912 2,352 2,836 3,358 3,908 4,487 5,094

4516 5,731 6,390 7,065 7,756 8,463 9,187 9,924 10,672 11,431 12,202

4517 12,984 13,774 14,569 15,370 16,177 16,989 17,806 18,627 19,452 20,281

4518 21,114 21,950 22,790 23,634 24,481 25,332 26,186 27,042 27,902 28,765

4519 29,631 30,500 31,371 32,244 33,120 33,999 34,880 35,764 36,650 37,539

4520 38,431 39,327 40,230 41,141 42,058 42,982 43,939 44,956 46,031 47,166

4521 48,360 49,595 50,851 52,129 53,428 54,749 56,091 57,452 58,832 60,232

4522 61,651 63,085 64,531 65,988 67,456 68,936 70,425 71,924 73,433 74,950

4523 76,477 78,013 79,560 81,117 82,684 84,261 85,849 87,448 89,058 90,679

4524 92,312 93,955 95,609 97,273 98,948 100,633 102,328 104,035 105,753 107,483

4525 109,223 110,973 112,732 114,499 116,276 118,061 119,854 121,656 123,465 125,283

4526 127,108 128,942 130,784 132,634 134,491 136,357 138,230 140,111 141,998 143,893

4527 145,795 147,704 149,619 151,541 153,469 155,404 157,345 159,293 161,246 163,206

4528 165,172 167,145 169,124 171,109 173,102 175,101 177,106 179,117 181,134 183,157

4529 185,186 187,220 189,260 191,304 193,354 195,408 197,468 199,531 201,600 203,672

4530 205,749 207,831 209,917 212,008 214,104 216,204 218,310 220,420 222,535 224,655

4531 226,780 228,910 231,044 233,182 235,324 237,470 239,620 241,775 243,933 246,096

4532 248,262 250,433 252,608 254,786 256,969 259,155 261,345 263,539 265,737 267,939

4533 270,145 272,353 274,566 276,782 279,001 281,224 283,450 285,679 287,911 290,147

4534 292,386 294,628 296,874 299,122 301,374 303,630 305,889 308,151 310,416 312,685
50

 CLEAR LAKE 2007 SURVEY

 AREA -CAPACITY TABLES (BOR VERTICAL DATUM, FEET)

CAPACITY TABLE IN ACRE-FEET

Elevation 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

4535 314,957 317,233 319,512 321,794 324,080 326,368 328,659 330,954 333,252 335,553

4536 337,857 340,165 342,476 344,790 347,108 349,429 351,755 354,083 356,415 358,751

4537 361,091 363,434 365,781 368,131 370,484 372,840 375,200 377,562 379,928 382,297

4538 384,669 387,045 389,423 391,805 394,189 396,577 398,968 401,362 403,759 406,160

4539 408,563 410,969 413,378 415,790 418,205 420,623 423,044 425,468 427,894 430,323

4540 432,756 435,191 437,629 440,071 442,515 444,964 447,415 449,870 452,329 454,790

4541 457,255 459,724 462,195 464,670 467,149 469,631 472,115 474,602 477,093 479,587

4542 482,084 484,585 487,090 489,597 492,108 494,623 497,142 499,664 502,190 504,719

4543 507,252 509,788 512,327 514,870 517,417 519,966 522,518 525,074 527,633 530,195

4544 532,760 535,328 537,900 540,475 543,054 545,635 548,220 550,808 553,400 555,995

4545 558,592 561,194 563,798 566,404 569,014 571,627 574,243 576,861 579,483 582,107

4546 584,735 587,365 589,999 592,635 595,274 597,917 600,563 603,212 605,864 608,518

4547 611,176 613,836 616,500 619,166 621,835 624,507 627,181 629,858 632,538 635,220

4548 637,905