Bathymetric and Sediment Survey of
Winfield City Lake, Cowley County, Kansas
Kansas Biological Survey
Applied Science and Technology for
Reservoir Assessment (ASTRA) Program
Report 2008-09 (March 2009)
Revised Area-Elevation-Capacity Tables and Figures, January 2010
This work was funded by the Kansas Water Office through the State
Water Plan Fund in support of the Reservoir Sustainability Initiative.
SUMMARY
During November 2007, the Kansas Biological Survey (KBS) performed a bathymetric survey
of Winfield City Lake in Cowley County, Kansas. The survey was carried out using acoustic
echosounding apparatus linked to a global positioning system.
A pre-impoundment topographic map of the reservoir site dated 1964 was obtained from the
City of Winfield. The map was scanned, georeferenced, and the contour lines digitized. A
digital elevation model of the pre-impoundment surface was then generated from the digitized
contour lines, and digitally compared to the 2007 reservoir bottom topography derived from
the bathymetric survey. Results of the comparison indicate that the reservoir has decreased
in volume by 1305 acre-feet since construction
Fourteen sediment cores were extracted from the lake on August 1, 2008 to determine
accumulated sediment thickness at locations distributed across the reservoir. Sediment
samples were taken from the top six inches of each core and analyzed for particle size
distributions.
Summary Data:
Bathymetric Survey:
Date of survey:
Water elevation on date of survey:
November 16, 2007
1255.8 ft.
Reservoir Statistics:
Area on survey date (acres):
Volume on survey date (acre-feet):
Maximum depth (feet):
1053
17,648
40.3
Elevation Benchmark (if applicable)
UTM location of elevation benchmark:
UTM Zone:
UTM datum:
686290.3, 4135789.2
14N
NAD83
Elevation of benchmark:
1256.3 ft.
Vertical datum, all data:
NAVD29
Sediment Survey:
Date of sediment survey:
August 1, 2008
TABLE OF CONTENTS
SUMMARY.....................................................................................................................i
TABLE OF CONTENTS................................................................................................ii
LIST OF FIGURES....................................................................................................... iii
LIST OF TABLES ........................................................................................................iv
LAKE HISTORY AND PERTINENT INFORMATION .................................................. 1
BATHYMETRIC SURVEYING PROCEDURE
Pre-survey preparation:..................................................................................... 3
Survey procedures: ........................................................................................... 3
Winfield Lake elevation benchmark:.................................................................. 4
Post-processing ................................................................................................ 6
BATHYMETRIC SURVEY RESULTS
Area-volume-elevation tables............................................................................ 9
PRE-IMPOUNDMENT MAP....................................................................................... 12
Pre-impoundment area-volume-elevation tables............................................. 16
SEDIMENT CORING AND SAMPLING..................................................................... 20
Sediment coring and sampling results ............................................................ 21
ii
LIST OF FIGURES
Figure 1.
Winfield Lake, Cowley County, Kansas . ..................................................... 1
Figure 2.
Location of Winfield City Lake in Cowley County, Kansas. .......................... 2
Figure 3.
a. Photo of overflow spillway on November 16, 2007 ................................. 4
b. Photo of overflow spillway on November 16, 2007 ................................. 4
Figure 4.
Bathymetric Survey Transects. .................................................................... 5
Figure 5.
Reservoir depth map ................................................................................... 8
Figure 6.
Cumulative area-elevation curve. .............................................................. 11
Figure 7.
Cumulative volume-elevation curve. .......................................................... 11
Figure 8.
Preimpoundment contour lines map. . ...................................................... 13
Figure 9.
Digitized preimpoundment contour lines map. ........................................... 14
Figure 10. Preimpoundment digital elevation model . ................................................. 15
Figure 11. Preimpoundment cumulative area-elevation curve .................................... 18
Figure 12. Preimpoundment cumulative volume-elevation curve................................ 18
Figure 13. Changes in lake-bottom elevation, 1964-2007........................................... 19
Figure 14. Map of sediment coring sites.. ................................................................... 23
Figure 15. Map of sediment thickness in centimeters at coring sites .......................... 24
Figure 16. Sediment particle size analysis.................................................................. 25
Figure 17. Map of sediment particle size distributions at coring sites.......................... 26
Figure 18. Comparison of sediment thicknesses as predicted by map
differencing versus actual values determined by sediment
coring......................................................................................................... 28
iii
LIST OF TABLES
Table 1.
Cumulative area in acres by tenth foot elevation increments...................... 9
Table 2.
Cumulative volume in acre-feet by tenth foot elevation
increments ................................................................................................. 10
Table 3.
Preimpoundment reservoir topography:
Cumulative area in acres by tenth foot elevation increments..................... 16
Table 4.
Preimpoundment reservoir topography:
Cumulative volume in acre-feet by tenth foot elevation
increments ................................................................................................. 17
Table 5.
Sediment coring site data .......................................................................... 22
Table 6.
Comparison of sediment thicknesses as predicted by map
differencing versus actual values determined by sediment
coring ......................................................................................................... 27
iv
LAKE HISTORY AND PERTINENT INFORMATION
(This section summarized with descriptions from The City of Winfield,
Kansas Dept. of Wildlife and Parks, and the National Inventory of Dams)
www.winfieldks.org
www.kdwp.state.ks.us
http://crunch.tec.army.mil/nidpublic/webpages/nid.cfm
Figure 1. Winfield Lake, Cowley County, Kansas (Photo: KBS)
Location: Located at 10348 141st Road, 8 miles northeast of Winfield. The City
Lake is 6 miles east of US-77 on Cowley Road 8 in the Walnut River Basin on
Timber Creek.
History of Construction: Designed by the Natural Resource Conservation
Service and the U.S. Department of Agriculture, primary construction of the
project was completed in 1970. The City of Winfield currently owns and operates
the reservoir and dam for water supply, flood control and storm water
management. .
Structure and Spillway Type: The project consists of an earthfill embankment
with an uncontrolled spillway 200 feet in length. The dam itself stretches a total
of 5,800 feet and rises to a height of 91 feet.
1
Cowley County, Kansas
Atlanta
Udall
Burden
Cambridge
Winfield
Dexter
Geuda Springs
Arkansas City
0 1.25 2.5
5
Figure 2. Location of Winfield City Lake in Cowley County, Kansas
2
7.5
Miles
10
Reservoir Bathymetric (Depth) Surveying Procedures
KBS operates a Biosonics DT-X acoustic echosounding system
(www.biosonicsinc.com) with a 200 kHz split-beam transducer and a 38-kHz singlebeam transducer. In addition to providing basic information on reservoir depth profiles,
the Biosonics system also permits the assessment of bottom sediment composition.
Latitude-longitude information is provided by a JRC global positioning system (GPS)
that interfaces with the Biosonics system. ESRI’s ArcGIS is used for on-lake navigation
and positioning, with GPS data feeds provided by the Biosonics unit through a serial
cable. Power is provided to the echosounding unit, command/navigation computer, and
auxiliary monitor by means of a inverter and battery backup device that in turn draw
power from the 12-volt boat battery.
Pre-survey preparation:
Geospatial reference data: Prior to conducting the survey, geospatial data of the target
lake is acquired, including georeferenced National Agricultural Imagery Project (NAIP)
photography. The lake boundary is digitized as a polygon shapefile from the FSA NAIP
georeferenced aerial photography obtained online from the Data Access and Service
Center (DASC) at the Kansas Geological Survey. Prior to the lake survey, a series of
transect lines are created as a shapefile in ArcGIS for guiding the boat during the
survey. Transect lines are spaced more closely (25-50 meters separation) on smaller
state/local lakes, while a spacing of 100-150 meters is used for federal reservoirs.
Survey procedures:
Calibration (Temperature and ball check): After boat launch and initialization of the
Biosonics system and command computer, system parameters are set in the Biosonics
Visual Acquisition software. The temperature of the lake at 1-2 meters is taken with a
research-grade metric electronic thermometer. This temperature, in degrees Celsius, is
input to the Biosonics Visual Acquisition software to calculate the speed of sound in
water at the given temperature at the given depth. Start range, end range, ping
duration, and ping interval are also set at this time. A ball check is performed using a
tungsten-carbide sphere supplied by Biosonics for this purpose. The ball is lowered to a
known distance (1.0 meter) below the transducer faces. The position of the ball in the
water column (distance from the transducer face to the ball) is clearly visible on the
echogram. The echogram distance is compared to the known distance to assure that
parameters are properly set and the system is operating correctly.
On-lake survey procedures: Using the GPS Extension of ArcGIS, the GPS data feed
from the GPS receiver via the Biosonics echosounder, and the pre-planned transect
pattern, the location of the boat on the lake in real-time is shown on the
command/navigation computer screen. To assist the boat operator in navigation, an
auxiliary LCD monitor is connected to the computer and placed within the easy view of
the boat operator. Transducer face depth on all dates is 0.5 meters below the water
surface. The transect pattern is maintained except when modified by obstructions in the
lake (e.g., partially submerged trees) or shallow water and mudflats. Data are
automatically logged in new files every half-hour (approximately 9000-ping files) by the
Biosonics system.
3
Winfield Lake Elevation Benchmark:
Winfield Lake does not have an active water elevation gauging system in the
manner of the federal reservoirs surveyed, nor does it have a visual gauge system in
the manner of Wellington City Lake. At the completion of the bathymetric survey on
November 16, 2007, the elevation of the water relative to the lip of the overflow spillway
(pictured below) was manually measured. The water surface on November 16, 2007
was 6 inches below the lip of the spillway. In subsequent email exchanges with Mr.
Russ Tomevi, Director of Public Works / Engineering for the City of Winfield, Mr. Tomevi
indicated that the elevation of the lip of the spillway was 1256.3 feet above sea level
(assumed vertical datum NAVD29), making the elevation of the water surface on
November 16, 2007 equal to 1255.8 feet above sea level. The elevation of the lip of
the spillway has not been independently confirmed by ASTRA by GPS or other surveys.
Figure 3a. Photo of overflow spillway on November 16, 2007.
Figure 3b. Photo of overflow spillway on November 16, 2007.
4
5
0
0 0.2
0.25
0.4
0.5
0.6
Figure 10. Preimpoundment digital elevation model.
Figure 4. Bathymetric Survey Transects for Winfield City Lake
2005 Perimeter
Legend
0.8
1
1
Miles Miles
Ü
Low : 1209.95
High : 1260.62
Elevation in feet AMSL
(NGVD 29)
Post-processing (Visual Bottom Typer)
The Biosonics DT-X system produces data files in a proprietary DT4 file format
containing acoustic and GPS data. To extract the bottom position from the acoustic
data, each DT4 file is processed through the Biosonics Visual Bottom Typer (VBT)
software. The processing algorithm is described as follows:
“The BioSonics, Inc. bottom tracker is an “end_up" algorithm, in that
it begins searching for the bottom echo portion of a ping from the last
sample toward the first sample. The bottom tracker tracks the bottom echo
by isolating the region(s) where the data exceeds a peak threshold for N
consecutive samples, then drops below a surface threshold for M samples.
Once a bottom echo has been identified , a bottom sampling window is
used to find the next echo. The bottom echo is first isolated by user_defined
threshold values that indicate (1) the lowest energy to include in the bottom
echo (bottom detection threshold) and (2) the lowest energy to start looking
for a bottom peak (peak threshold). The bottom detection threshold allows
the user to filter out noise caused by a low data acquisition threshold. The
peak threshold prevents the algorithm from identifying the small energy
echoes (due to fish, sediment or plant life) as a bottom echo.” (Biosonics
Visual Bottom Typer User’s Manual, Version 1.10, p. 70).
Data is output as a comma-delimited (*.csv) text file. A set number of qualifying pings
are averaged to produce a single report (for example, the output for ping 31 {when
pings per report is 20} is the average of all values for pings 12-31). Standard analysis
procedure for all 2008 and later data is to use the average of 7 pings to produce one
output value.
All raw *.csv files are merged into one master *.csv file using the shareware program
File Append and Split Tool (FAST) by Boxer Software (Ver. 1.0, 2006).
Post-processing (Excel)
The master *.csv file created by the FAST utility is imported into Microsoft Excel.
Excess header lines are deleted (each input CSV file has its own header), and the
header file is edited to change the column headers “#Ping” to “Ping” and “E1’ “ to “E11”,
characters that are not ingestable by ArcGIS. Entries with depth values of zero (0) are
deleted, as are any entries with depth values less than the start range of the data
acquisition parameter (typically 0.49 meters or less) (indicating areas where the water
was too shallow to record a depth reading).
In Excel, depth adjustments are made. A new field – Adj_Depth – is created. The value
for AdjDepth is calculated as AdjDepth = Depth + (Transducer Face Depth), where the
Transducer Face Depth represents the depth of the transducer face below water level in
meters (Typically, this value is 0.5 meters). Four values are computed in Excel:
DepthM, DepthFt, ElevM and ElevFt, where:
6
DepthM = Adj_Depth
DepthFt = Adj_Depth * 3.28084
These water depths are RELATIVE water depths that can vary from day-to-day based
on the elevation of the water surface. In order to normalize all depth measurements to
an absolute reference, water depths must be subtracted from an established value for
the elevation of the water surface at the time of the bathymetric survey. Determination
of water surface elevation has been described in an earlier section on establishment of
lake levels.
To set depths relative to lake elevation, another field is added to the attribute table of
the point shapefile, ElevM. The value for this attribute is then computed as
Depth_ElevM = (Elevation of the Water Surface in meters above sea level) - Adj_Depth.
Elevation of the water surface in feet above sea level is also computed by converting
ElevM to elevation in feet (ElevM * 3.28084).
Particularly for multi-day surveys, ADJ_DEPTH, Depth_M, and Depth_Ft should NOT
be used for further analysis or interpolation. If water depth is desired, it should be
produced by subtracting Elev_M or Elev_Ft from the reference elevation used for
interpolation purposes (for federal reservoirs, the elevation of the water surface on the
day that the aerial photography from which the lake perimeter polygon was digitized).
Post-processing (ArcGIS):
Ingest to ArcGIS is accomplished by using the Tools – Add XY Data option. The
projection information is specified at this time (WGS84). Point files are displayed as
Event files, and are then exported as a shapefile (filename convention:
ALLPOINTS_WGS84.shp). The pointfile is then reprojected to the UTM coordinate
system of the appropriate zone (14 or 15) (filename convention ALLPOINTS_UTM.shp).
Raster interpolation of the point data is performed using the same input data and the
Topo to Raster option within the 3D Extension of ArcGIS. The elevation of the reservoir
on the date of aerial photography used to create the perimeter/shoreline shapefile was
used as the water surface elevation in all interpolations from point data to raster data.
Contour line files are derived from the raster interpolation files using the ArcGIS
command under 3D Analyst – Raster Surface – Contour.
Area-elevation-volume tables are derived using an ArcGIS extension custom written for
and available from the ASTRA Program. Summarized, the extension calculates the
area and volume of the reservoir at 1/10-foot elevation increments from the raster data
for a series of water surfaces beginning at the lowest elevation recorded and
progressing upward in 1/10-foot elevation increments to the reference water surface.
Cumulative volume is also computed in acre-feet.
7
8
0
0.2
0.4
0.25
0.5
0.6
Figure 10. Preimpoundment digital elevation model.
Perimeter
Figure 5. 2005
Water
depth based on November 2007 bathymetric survey.
Depths are based on a pool elevation of 1255.8 feet.
Legend
0
0.8
1
Miles 1
Miles
Ü
4 Ft. Contours
32.01 - 36.00
Low : 1209.95
28.01 - 32.00
24.01 - 28.00
High : 1260.62
16.01 - 20.00
Elevation in feet AMSL
20.01 - 24.00
(NGVD 29)
12.01 - 16.00
8.01 - 12.00
4.01 - 8.00
0.00 - 4.00
Depth in Feet
Table 1
Cumulative area in acres by tenth foot elevation increments
Elevation
(ft NGVD)
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
9
29
51
65
79
99
117
133
148
163
184
204
224
239
255
280
306
328
351
374
401
426
452
479
505
530
557
587
616
649
683
719
757
798
838
873
907
938
967
1002
11
31
53
66
81
101
119
135
149
164
186
206
225
240
258
283
308
330
354
377
403
429
454
481
507
533
560
590
619
652
686
723
761
802
842
877
910
941
970
1006
13
35
54
67
83
103
120
136
151
166
188
208
227
241
260
286
310
333
356
379
406
431
457
484
510
536
562
593
622
656
690
727
765
806
845
880
914
944
973
1011
1
15
37
56
69
85
105
121
138
152
168
191
210
228
243
262
288
312
335
358
382
409
434
459
486
513
538
565
596
625
659
693
731
769
810
849
883
917
947
977
1015
1
17
40
57
70
87
107
123
140
154
171
192
212
230
244
265
291
314
338
361
384
411
437
462
489
515
541
568
599
629
662
697
734
773
814
852
887
920
950
980
1020
2
19
42
58
71
89
109
125
141
155
173
194
214
231
246
267
294
317
340
363
387
414
439
465
492
518
544
571
602
632
666
700
738
777
818
856
890
923
952
983
1026
3
21
44
59
73
91
110
126
142
156
175
196
217
233
248
270
296
319
342
365
389
416
442
468
494
520
546
574
604
636
669
704
742
781
822
860
893
926
955
987
1031
4
23
46
61
74
93
112
128
144
158
178
198
219
234
249
272
299
321
344
367
392
419
444
471
497
523
549
577
607
639
672
708
746
785
826
863
897
929
958
990
1038
6
25
48
62
76
95
114
130
145
159
180
200
221
236
251
275
301
323
346
370
395
421
447
473
499
525
552
580
610
642
676
711
750
789
830
867
900
932
961
994
1053
7
27
49
63
77
97
116
131
147
161
182
202
222
237
253
278
304
325
349
372
398
424
449
476
502
528
554
584
613
646
680
715
753
793
834
870
903
935
964
998
0
9
Table 2
Cumulative volume in acre-feet by tenth foot elevation increments
Elevation
(ft NGVD)
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
3
22
63
122
193
282
390
516
656
811
985
1179
1394
1625
1871
2139
2432
2749
3089
3452
3840
4253
4693
5158
5650
6169
6712
7285
7887
8518
9185
9886
10625
11403
12221
13078
13969
14892
15846
16830
4
25
69
128
201
292
402
529
671
828
1003
1199
1416
1649
1897
2167
2463
2782
3124
3489
3880
4296
4738
5206
5701
6222
6768
7343
7948
8584
9253
9958
10701
11483
12305
13165
14059
14986
15942
16931
6
29
74
135
209
302
414
543
686
844
1022
1220
1438
1672
1923
2195
2494
2815
3160
3528
3921
4339
4784
5255
5752
6275
6825
7403
8010
8649
9323
10031
10778
11563
12390
13254
14151
15081
16040
17032
7
33
80
141
217
313
426
556
701
861
1041
1241
1461
1697
1949
2224
2525
2848
3196
3566
3961
4382
4829
5303
5803
6329
6880
7462
8072
8715
9392
10104
10854
11644
12474
13342
14242
15175
16137
17133
8
36
85
149
226
323
439
569
716
878
1060
1262
1484
1721
1975
2253
2557
2883
3231
3604
4002
4426
4876
5352
5855
6382
6937
7521
8136
8781
9461
10178
10931
11725
12560
13430
14334
15270
16235
17234
1
10
40
91
155
235
334
451
584
732
896
1080
1283
1507
1746
2002
2283
2588
2916
3267
3643
4043
4470
4922
5401
5906
6437
6995
7582
8198
8848
9531
10251
11009
11807
12645
13519
14427
15365
16333
17338
1
12
45
97
163
244
345
464
598
748
912
1099
1305
1530
1771
2029
2312
2620
2951
3305
3682
4085
4514
4968
5451
5958
6491
7052
7642
8262
8914
9602
10325
11086
11889
12730
13608
14519
15461
16432
17440
1
15
49
103
170
253
356
477
612
764
930
1119
1327
1553
1796
2056
2342
2651
2985
3341
3721
4127
4559
5016
5500
6010
6546
7110
7703
8325
8982
9672
10400
11165
11971
12817
13698
14612
15557
16531
17544
2
17
54
109
177
263
367
489
627
779
949
1138
1349
1577
1821
2083
2372
2684
3019
3378
3760
4169
4602
5063
5550
6063
6602
7167
7764
8389
9049
9743
10474
11244
12054
12903
13788
14705
15652
16631
17648
2
20
59
115
185
272
379
502
641
795
966
1159
1371
1601
1846
2111
2402
2716
3054
3415
3800
4211
4648
5111
5600
6116
6656
7226
7824
8454
9117
9814
10549
11323
12138
12991
13878
14799
15749
16730
10
11
Figure 7. Cumulative volume-elevation curve
Elevation (feet)
12
12
12
12
12
12
12
12
12
49
47
45
43
41
39
37
35
33
31
29
27
25
23
21
19
17
15
55
53
51
12
12
12
12
12
12
12
12
12
12
12
12
Cumulative Volume (acre-feet)
12
12
12
12
53
51
49
47
45
43
41
39
37
35
33
31
29
27
25
23
21
19
17
15
55
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
Cumulative Area (acres)
1200
1000
800
600
400
200
0
Elevation (feet)
Figure 6. Cumulative area-elevation curve
20000
18000
16000
14000
12000
10000
8000
6000
4000
2000
0
PRE-IMPOUNDMENT MAP
Caution should be exercised in drawing conclusions based on comparison
between two maps of different scales, dates, and production methods.
A pre-impoundment topographic map dated 1964 with a contour interval of four feet (4’)
prepared by Wilson and Co. was obtained in paper form from the City of Winfield
Director of Public Works/Engineering (Figure 8). The map was scanned into a TIF
format at 600 dpi resolution by the University of Kansas Map Library Services. The TIF
file was then georeferenced to the Universal Transverse Mercator (UTM) projection,
NAD83, Zone 14, using the ArcGIS Georeferencing Tool. Control points were located
on the 1964 maps at section corners and referenced to corresponding locations on a
UTM-georeferenced USGS Digital Raster Graphic (DRG) topographic map. A secondorder polynomial transformation was computed from the coordinate pairs, and the 1964
map were resampled to the UTM coordinate system using a nearest-neighbor algorithm.
Contour lines were manually digitized to a polyline shapefile and attributed (Figure 9).
All contour intervals at elevations 1260 feet and below were digitized (every four feet of
vertical). The ArcGIS TIN tool was then used to generate a Triangulated Irregular
Network (TIN) for the reservoir. The TIN file was then converted to a raster file (Digital
Elevation Model, or DEM) to facilitate comparison of elevations to the 2007 bathymetric
data (present-day lake bottom elevations) (Figure 10).
Changes in lake bottom elevation between 1964 and 2007 were computed by digitally
subtracting the 1964 digital elevation model from the 2007 digital elevation model.
Negative numbers on the resulting output indicate 2007 elevation lower than 1964
elevation (loss of material during the 43-year period); positive numbers indicate 2007
lake bottom higher than 1964 (accumulated material, or likely siltation) (Figure 11).
Area-volume-elevation tables (Table 3 and 4) and graphs of cumulative area and
volume (Figures 11 and 12, respectively) were computed for the preimpoundment DEM
using an ArcGIS extension custom written for the ASTRA Program. The extension
calculates the area and volume of the reservoir at 1/10-foot elevation increments from
the raster data for a series of water surfaces beginning at the lowest elevation recorded
and progressing upward in 1/10-foot elevation increments to the reference water
surface.
As the contour interval is four (4) feet, areas of ± 2 feet difference are not shown on the
difference map. The difference map suggests that the greatest sedimentation has
occurred in the former river channel, as might be expected; furthermore, the majority of
the non-river channel silt accumulation has occurred in the upper part of the reservoir
(Figure 13; light- to dark-green colors).
12
13
0.5
2005 Perimeter
Legend
0.125 0.25
0.75
1
Miles
0
0.25
Figure 10. Preimpoundment digital elevation model.
0.5
2005 Perimeter
Legend
Figure 8. Scanned preimpoundment contour lines map
0
1
Miles
Ü
Low : 1209.95
High : 1260.62
Elevation in feet AMSL
(NGVD 29)
14
0.5
2005 Perimeter
Legend
0.125 0.25
0.75
1
Miles
0
0.25
Figure 10. Preimpoundment digital elevation model.
0.5
2005 Perimeter
Legend
Figure 9. Digitized preimpoundment contour lines map
0
1
Miles
Ü
Low : 1209.95
High : 1260.62
Elevation in feet AMSL
(NGVD 29)
15
0.5
2005 Perimeter
Legend
0.125 0.25
0.75
1
Miles
0
0.25
Figure 10. Preimpoundment digital elevation model.
0.5
2005 Perimeter
Legend
Figure 10. Preimpoundment digital elevation model.
0
1
Miles
Ü
Low : 1209.95
High : 1260.62
Low : 1209.95
(NGVD
High29)
: 1260.62
Elevation in feet AMSL
(NGVD
29) in feet AMSL
Elevation
Table 3
Preimpoundment reservoir topography
Cumulative area in acres by tenth foot elevation increments
Elevation (ft
NGVD)
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
0.00
1
6
14
21
29
47
70
82
92
109
128
141
153
170
190
205
221
259
295
311
326
348
372
390
406
431
457
475
492
522
557
581
603
634
676
709
740
786
835
873
907
946
981
1006
1027
0.10
1
7
15
22
30
53
71
83
93
113
130
142
155
173
191
206
223
271
297
313
328
353
374
391
408
437
459
477
494
529
560
583
605
641
680
712
744
798
839
876
910
954
984
1009
1029
0.20
1
8
16
23
32
55
73
84
94
115
131
143
156
175
193
208
225
275
299
314
330
355
376
393
411
439
461
479
496
533
562
585
607
645
683
715
748
803
843
880
914
957
986
1011
1031
0.30
2
9
16
24
33
57
74
85
96
116
132
145
157
177
195
209
227
279
300
315
332
357
378
395
413
442
463
481
498
536
565
587
610
650
687
719
752
808
847
883
917
960
989
1013
1032
16
0.40
2
10
17
25
34
59
75
86
97
118
133
146
158
179
196
211
228
282
302
317
334
359
379
396
415
444
465
482
500
539
567
589
613
653
690
722
756
812
851
886
921
963
992
1015
1034
0.50
2
11
18
25
35
61
76
87
99
120
134
147
160
181
198
213
231
285
303
318
336
361
381
398
416
446
467
484
503
542
569
592
616
657
693
724
759
816
854
890
925
966
994
1018
1036
0.60
3
12
18
26
37
63
77
88
100
122
136
148
161
183
199
214
234
287
305
320
337
363
383
400
418
448
469
485
505
545
572
594
618
661
696
728
763
820
858
893
928
969
996
1020
1037
0.70
3
12
19
27
38
65
78
89
101
123
137
149
163
184
200
216
238
289
306
321
339
366
384
401
421
451
470
487
508
548
574
596
621
665
700
731
767
824
862
896
932
972
999
1022
1038
0.80
3
13
20
28
40
67
80
90
104
125
138
150
164
186
202
217
243
292
308
323
341
368
386
403
423
453
472
489
510
552
576
598
623
669
703
734
771
828
865
900
935
976
1001
1024
1039
0.90
4
14
21
29
43
69
81
91
106
127
139
152
166
188
204
219
247
293
309
324
343
370
388
405
426
455
474
490
514
554
578
600
626
673
706
737
775
832
869
903
938
979
1004
1026
Table 4
Pre-impoundment reservoir topography
Cumulative volume in acre-feet by tenth foot elevation increments
Elevation (ft
NGVD)
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
0.00
0
3
13
31
56
92
153
229
316
415
535
669
816
977
1157
1355
1568
1801
2085
2388
2706
3042
3404
3785
4183
4601
5047
5514
5998
6502
7044
7613
8205
8821
9479
10172
10898
11658
12474
13329
14219
15145
16112
17106
18125
0.10
0
3
15
33
59
97
160
237
325
426
548
683
832
994
1176
1376
1590
1828
2114
2419
2739
3077
3441
3824
4224
4644
5093
5561
6047
6554
7100
7672
8266
8885
9547
10243
10972
11738
12558
13416
14310
15240
16210
17207
18228
0.20
0
4
16
35
62
103
167
246
335
438
561
698
847
1011
1196
1396
1612
1855
2144
2451
2772
3113
3479
3863
4265
4688
5139
5609
6096
6607
7156
7730
8326
8950
9615
10315
11047
11818
12642
13504
14401
15336
16309
17308
18331
0.30
1
5
18
38
66
108
175
254
344
449
574
712
863
1029
1215
1417
1635
1883
2174
2482
2805
3149
3516
3903
4306
4732
5185
5657
6146
6661
7212
7789
8387
9015
9684
10387
11122
11898
12727
13592
14493
15432
16407
17410
18434
17
0.40
1
6
19
40
69
114
182
263
354
461
587
727
879
1047
1235
1438
1658
1911
2204
2514
2838
3184
3554
3942
4348
4776
5231
5705
6196
6715
7269
7848
8449
9080
9752
10459
11197
11979
12811
13681
14585
15528
16507
17511
18537
0.50
1
7
21
43
72
120
190
271
363
473
601
741
895
1065
1254
1459
1681
1940
2234
2545
2872
3221
3592
3982
4389
4821
5278
5754
6246
6769
7326
7907
8510
9145
9822
10531
11273
12061
12897
13770
14677
15624
16606
17613
18641
0.60
1
8
23
45
76
126
197
280
373
485
614
756
911
1083
1274
1481
1704
1968
2265
2577
2906
3257
3631
4022
4431
4866
5325
5802
6297
6823
7383
7966
8572
9211
9891
10604
11349
12143
12982
13859
14770
15721
16705
17715
18745
0.70
1
9
25
48
80
133
205
289
383
497
628
771
927
1101
1294
1502
1728
1997
2295
2609
2939
3293
3669
4062
4473
4911
5372
5851
6348
6878
7440
8025
8634
9278
9961
10677
11426
12225
13068
13948
14863
15818
16805
17817
18849
0.80
2
10
27
51
84
139
213
298
394
510
641
786
943
1120
1314
1524
1752
2026
2326
2641
2973
3330
3707
4102
4515
4956
5419
5899
6398
6933
7498
8085
8696
9344
10031
10750
11503
12308
13155
14038
14957
15916
16905
17919
18953
0.90
2
12
29
53
88
146
221
307
404
522
655
801
960
1139
1335
1546
1776
2055
2357
2674
3008
3367
3746
4143
4558
5001
5466
5948
6450
6988
7555
8145
8758
9411
10101
10824
11580
12391
13242
14129
15050
16014
17006
18022
1200
1000
Cumulative Area (acres)
1964 Area
2007 Area
800
600
400
200
12
10
12
12
12
14
12
16
12
18
12
20
12
22
12
24
12
26
12
28
12
30
12
32
12
34
12
36
12
38
12
40
12
42
12
44
12
46
12
48
12
50
12
52
12
54
0
E l e v a t i on ( f e e t )
Figure 11. Pre-impoundment cumulative area-elevation curve.
20000
18000
1964 Volume
2007 Volume
Cumulative Volume (acre-feet)
16000
14000
12000
10000
8000
6000
4000
2000
12
10
12
12
12
14
12
16
12
18
12
20
12
22
12
24
12
26
12
28
12
30
12
32
12
34
12
36
12
38
12
40
12
42
12
44
12
46
12
48
12
50
12
52
12
54
0
E l e v at i on ( f e e t )
Figure 12. Pre-impoundment cumulative volume-elevation curve.
18
19
0.2
0.4
0.6
0.8
1
Miles
Figure 13. Change in lake-bottom elevation, 1964 (pre-impoundment) to 2007.
Negative values indicate 2007 elevation lower than 1964 elevation;
Positive values indicate 2007 lake bottom higher than 1964.
0
+14.01 - +46.00
+12.01 - +14.00
+10.01 - +12.00
+8.01 - +10.00
+6.01 - +8.00
+4.01 - +6.00
+2.01 - +4.00
+0.01 - +2.00
-1.99 - 0.00
-3.99 - -2.00
-5.99 - -4.00
-7.99 - -6.00
-9.99 - -8.00
-11.99 - -10.00
-13.99 - -12.00
-16.00 - -14.00
Difference in Feet
SEDIMENT CORING/SAMPLING PROCEDURES
KBS operates a Specialty Devices Inc.
sediment vibracorer mounted on a dedicated
24’ pontoon boat. The vibracorer uses 3”
diameter aluminum thinwall pipe in userspecified lengths (KBS has used up to 10’
sections). The vibracorer runs off 24-volt
batteries, and uses an electric motor with
counter-rotating weights in the vibracorer
head unit to create a high-frequency vibration
in the pipe, allowing the pipe to penetrate
even solidly packed sediments and substrate
as it is lowered into the lake using a manually
operated winch system. Once the open end
of the core pipe has penetrated to the
substrate, the unit is turned off and the unit is
raised to the surface using the winch. At the
surface, the pipe containing the sediment
core is disconnected from the vibracore head
for further onboard processing. The
sediment core can be cut into sections while
in the pipe, the pipe bisected longitudinally
for taking samples along the length of the
core, or the sediment can be manually
extruded from the pipe and measured.
KBS vibe-core system.
At each site, determined using GPS, the core boat is anchored and the vibracore
system used to extract a sediment core down to and including the upper several inches
of pre-impoundment soil (substrate). The location of each core site is recorded using a
GPS linked to a laptop running ArcGIS and the ArcGIS GPS extension. Cores are
carefully extruded from the core pipe, and the interface between sediment and substrate
identified. Typically, this identification is relatively easy, with the interface being
identifiable by changes in material density and color, and the presence of roots or sticks
in the substrate. For most analyses, the top six inches of sediment are collected and
sealed in a sampling container. Samples are then shipped to MidWest Laboratories
(Omaha, NE), for texture, bulk density, and other analyses.
20
Sediment Coring and Sampling Results:
Sampling sites were distributed across the length and breadth of the reservoir (Figure
14). An effort was made to avoid the original stream channel, which would have likely
yielded higher sediment thicknesses not representative of the overall reservoir bottom
sediment thickness. Referring back to the reservoir depth map (Figure 5) and the preimpoundment map (Figures 8-10), the original stream channel generally follows the
southern side of the reservoir, resulting in a fairly gentle slope across the northern part
and steep dropoffs along the southern shore.
Sediment thickness ranged from a low of 4 centimeters at site WIN-9 (located in the
north-central part of the reservoir)(Figure 15, Table 3) to a high of 170 centimeters at
site WIN-13 adjacent to the dam. Average sediment thickness across all fourteen sites
was 60 centimeters. Contrary to pre-coring expectations, highest sediment thicknesses
were not found in the upper end of the reservoir near the inflow (Sites WIN-1 and WIN2), but in the lower end of the reservoir near the dam (Sites WIN-12, -13, and –
14)(Table 5).
Sample site particle size distributions form distinct trends across the reservoir. Sites in
the eastern half (WIN-1 to WIN-4, WIN-6, -8, and –9) generally are dominated by silt,
with clay forming a secondary fraction and sand a minor to very minor percentage of the
total (Figure 16, Figure 17). Sites in the western half (WIN-10 through WIN-14), in
contrast, exhibit a high sand percentage with clay again forming a secondary fract, but
with strikingly low fractions of silt (Figure 16, Figure 17).
Actual sediment thickness values as determined by coring were compared to values
from the 1964-2007 (pre-impoundment versus bathymetry) map (Figure 13) for each
sample site. This comparison provides some insight into the validity and accuracy of
the preimpoundment map differencing approach. Results suggest that the map
differencing generally underestimates the sediment accumulation in this reservoir (Table
6; Figure 18).
21
Table 5
Winfield City Lake Sediment Coring Site Data
Sediment
Thickness
(cm)
Bulk
Density
(g/cm3)
Sand
(%)
Silt
(%)
Clay
(%)
4137054.1
64
1.13
14
64
22
690251.8
4136807.8
64
1.13
6
72
22
WIN-3
689822.4
4136597.1
37
1.16
4
72
24
WIN-4
689755.5
4136237.6
24
1.15
4
72
24
WIN-5
689103.0
4136316.6
48
1.21
50
30
20
WIN-6
689028.1
4136023.2
12
1.23
10
76
14
WIN-7
688590.3
4136016.3
80
1.23
34
35
31
WIN-8
688615.5
4136431.3
25
1.31
8
68
24
WIN-9
687988.6
4136304.5
4
1.21
10
64
26
WIN-10
687901.3
4135664.2
44
1.12
66
14
20
WIN-11
687160.6
4136154.4
26
1.13
66
12
22
WIN-12
687137.8
4135733.9
152
1.07
50
10
40
WIN-13
686477.6
4136129.3
170
1.08
40
15
45
WIN-14
686423.2
4135811.8
90
1.10
33
21
46
Code
UTMX
UTMY
WIN-1
690657.4
WIN-2
Coordinates are Universal Transverse Mercator (UTM), NAD83, Zone 14 North
22
23
!
.
WIN-12
!
.
!
.
0
0 0.2
WIN-10
0.25
0.4
Figure 10. Preimpoundment digital elevation model.
Figure 14. Sediment Coring Sites in Winfield City Lake
2005 Perimeter
Legend
!
.
WIN-14
!
.
WIN-13
WIN-11
!
.
WIN-9
!
.
0.5
0.6
WIN-7
!
.
WIN-8
0.8
!
.
WIN-6
!
.
WIN-5
1
1
Miles Miles
!
.
WIN-4
!
.
WIN-3
High : 1260.62
Ü
Low : 1209.95
Elevation in feet AMSL
(NGVD 29)
!
.
WIN-2
!
.
WIN-1
24
!
.
152
!
.
26
0
!
.
44
0 0.2
0.25
0.4
!
.
80
!
.
0.5
0.6
0.8
!
.
12
!
.
48
Figure 10. Preimpoundment digital elevation model.
!
.
24
!
.
1
1
Miles Miles
Figure 15. Sediment thickness in centimeters at coring sites in Winfield City Lake
2005 Perimeter
Legend
!
.
90
!
.
170
!
.
4
25
37
High : 1260.62
Ü
Low : 1209.95
Elevation in feet AMSL
(NGVD 29)
!
.
64
!
.
64
Winfield City Lake
2008 Sediment Particle Size Analysis
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
% Clay
% Silt
%Sand
Sample Site
Figure 16. Sediment particle size analysis.
25
26
WIN-12
0
0 0.2
WIN-10
0.25
0.4
0.5
0.6
WIN-7 WIN-6
0.8
WIN-5
Figure 10. Preimpoundment digital elevation model.
Figure 17. Sediment Particle Size Distributions in Winfield City Lake
2005 Perimeter
Legend
WIN-14
WIN-13
WIN-11
WIN-9
WIN-8
1
1
Miles Miles
WIN-4
WIN-3
Ü
Low : 1209.95
% Silt
% Clay
% :Sand
High
1260.62
Elevation in feet AMSL
(NGVD 29)
Proportions of
sand/silt/clay
WIN-2
WIN-1
Table 6
Comparison of sediment thicknesses as predicted by map differencing
versus actual values determined by sediment coring
Sediment thickness
from coring
(cm)
Sediment thickness
from map differencing
(cm)
4137054.1
64
214
690251.8
4136807.8
64
12
WIN-3
689822.4
4136597.1
37
-31
WIN-4
689755.5
4136237.6
24
10
WIN-5
689103.0
4136316.6
48
50
WIN-6
689028.1
4136023.2
12
29
WIN-7
688590.3
4136016.3
80
62
WIN-8
688615.5
4136431.3
25
25
WIN-9
687988.6
4136304.5
4
21
WIN-10
687901.3
4135664.2
44
86
WIN-11
687160.6
4136154.4
26
-75
WIN-12
687137.8
4135733.9
152
79
WIN-13
686477.6
4136129.3
170
-45
WIN-14
686423.2
4135811.8
90
29
Code
UTMX
UTMY
WIN-1
690657.4
WIN-2
27
250
Sediment thickness by map difference (cm.)
WIN-1
200
WIN-10
WIN-7
150
100
WIN-12
WIN-5
50
WIN-14
WIN-6 WIN-8
WIN-9
WIN-4
0
WIN-2
WIN-3
WIN-13
-50
WIN-11
-100
0
50
100
150
200
250
Sediment thickness by coring (cm.)
Figure 18. Comparison of sediment thicknesses as predicted by map differencing versus actual
values determined by sediment coring. The red line represents equal values, i.e., actual (cored)
sediment thickness equal to the predicted (map difference). For sites BELOW the red line,
sediment thickness as determined by coring was greater than sediment thickness predicted by
map differencing.
28