Prepared in cooperation with Northern Arizona University

Colorado River Campsite Monitoring, Grand Canyon National
Park, Arizona, 1998–2012

Open-File Report 2014-1161

U.S. Department of the Interior
U.S. Geological Survey

Colorado River Campsite Monitoring, Grand Canyon
National Park, Arizona, 1998–2012

By Matt Kaplinski, Joe Hazel, Rod Parnell, Daniel R. Hadley, and Paul Grams

Prepared in cooperation with Northern Arizona University

Open-File Report 2014–1161

U.S. Department of the Interior
U.S. Geological Survey

U.S. Department of the Interior
SALLY JEWELL, Secretary
U.S. Geological Survey
Suzette M. Kimball, Acting Director
U.S. Geological Survey, Reston, Virginia: 2014

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Suggested citation:
Kaplinski, Matt, Hazel, Joe, Parnell, Rod, Hadley, D.R., and Grams, Paul, 2014, Colorado River campsite monitoring,
Grand Canyon National Park, Arizona, 1998–2012: U.S. Geological Survey Open-File Report 2014-1161, 24 p. plus
appendix, http://dx.doi.org/10.3133/ofr20141161.
ISSN 2331-1258 (online)

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Contents
Abstract ......................................................................................................................................................................... 1
Introduction .................................................................................................................................................................... 1
Purpose and Scope ................................................................................................................................................... 2
Study Area, Place Names, and Units ......................................................................................................................... 2
Glen Canyon Dam Flows Releases during Study Period ........................................................................................... 4
Methods ......................................................................................................................................................................... 5
Study Design and Site Selection ................................................................................................................................ 5
Data Collection and Processing ................................................................................................................................. 7
Results and Conclusions ..............................................................................................................................................20
Acknowledgments ........................................................................................................................................................20
References Cited ..........................................................................................................................................................21
Appendix A. Campsite Area Data for Each Study Site..................................................................................................24

Figures
Figure 1. Map showing campsite area study site locations along the Colorado River, Grand Canyon
National Park, Arizona ................................................................................................................................................... 3
Figure 2. Hydrograph showing the Colorado River at Lees Ferry (09380000), Arizona, 1998–2013 ............................ 4
Figure 3. Map showing repeat surveys of Nautiloid camp (RM 35.0) conducted on October 12, 1998 at 16:00
and 17:00 by independent survey crews ....................................................................................................................... 9
Figure 4. Time series plots showing mean campsite area for all sites along the Colorado River, Grand Canyon
National Park, Arizona ................................................................................................................................................. 17
Figure 5. Time series plots showing mean campsite area for sites in Marble and Grand Canyons along the
Colorado River, Grand Canyon National Park, Arizona ............................................................................................... 18
Figure 6. Time series plots showing mean campsite area for sites in critical and non-critical recreational segments
along the Colorado River, Grand Canyon National Park, Arizona ............................................................................... 19

Tables
Table 1. Campsite monitoring study sites, along the Colorado River, Grand Canyon National Park, Arizona .............. 6
Table 2. Campsite survey trip data collected along the Colorado River, Grand Canyon National Park,
Arizona, 1998–2012....................................................................................................................................................... 8
Table 3. Mean campsite area for all sites in low, high, and total stage elevation zones along the Colorado River,
Grand Canyon National Park, Arizona, 1998–2012 ..................................................................................................... 11
Table 4. Mean campsite area for sites in low, high, and total stage elevation zones in Marble Canyon along the
Colorado River, Arizona, 1998–2012........................................................................................................................... 12
Table 5. Mean campsite area for sites in low, high, and total stage elevation zones in Grand Canyon along the
Colorado River, Grand Canyon National Park, Arizona, 1998–2012 ........................................................................... 13
Table 6. Mean campsite area for sites in critical reaches in low, high, and total stage elevation zones along the
Colorado River, Grand Canyon National Park, Arizona, 1998–2012 ........................................................................... 14
Table 7. Mean campsite area for sites in non-critical reaches in low, high, and total stage elevation zones
along the Colorado River, Grand Canyon National Park, Arizona, 1998–2012 ........................................................... 15
Table 8. Results of linear regression of mean campsite-area time series presented in tables 2 through 6,
Grand Canyon National Park, Arizona, 1998–2012 ..................................................................................................... 16
iii

Conversion Factors
Inch/Pound to SI
Multiply

By

To obtain

Length
foot (ft)

0.3048

meter (m)

mile (mi)

1.609

kilometer (km)

Area
2

square foot (ft )

square meter (m2)

0.09290
Volume

cubic foot (ft3)

cubic meter (m3)

0.02832
Flow rate

cubic foot per second (ft3/s)

cubic meter per second (m3/s)

0.02832

SI to Inch/Pound
Multiply

By

To obtain

Length
meter (m)

3.281

foot (ft)

kilometer (km)

0.6214

mile (mi)

Volume
3

cubic meter (m )

cubic foot (ft3)

35.31
Flow rate
3

cubic meter per second (m /s)

cubic foot per second (ft3/s)

35.31

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).
Elevation, as used in this report, refers to distance above the vertical datum.

iv

Colorado River Campsite Monitoring,
Grand Canyon National Park, Arizona, 1998–2012
By Matt Kaplinski, Joe Hazel, Rod Parnell, Daniel R. Hadley, and Paul Grams

Abstract
River rafting trips and hikers use sandbars along the Colorado River in Marble and Grand
Canyons as campsites. The U.S. Geological Survey evaluated the effects of Glen Canyon Dam
operations on campsite areas on sandbars along the Colorado River in Grand Canyon National Park.
Campsite area was measured annually from 1998 to 2012 at 37 study sites between Lees Ferry and
Diamond Creek, Arizona. The primary purpose of this report is to present the methods and results of the
project.
Campsite area surveys were conducted using total station survey methods to outline the
perimeter of camping area at each study site. Campsite area is defined as any region of smooth substrate
(most commonly sand) with no more than an 8 degree slope and little or no vegetation. We used this
definition, but relaxed the slope criteria to include steeper areas near boat mooring locations where
campers typically establish their kitchens.
The results show that campsite area decreased over the course of the study period, but at a rate
that varied by elevation zone and by survey period. Time-series plots show that from 1998 to 2012, high
stage-elevation (greater than the 25,000 ft3/s stage-elevation) campsite area decreased significantly,
although there was no significant trend in low stage-elevation (15,000–20,000 ft3/s) campsite area. High
stage-elevation campsite area increased after the 2004 and 2008 high flows, but decreased in the
intervals between high flows. Although no overall trend was detected for low stage-elevation campsite
areas, they did increase after high-volume dam releases equal to or greater than about 20,000 ft3/s. We
conclude that dam operations have not met the management objectives of the Glen Canyon Adaptive
Management program to increase the size of camping beaches in critical and non-critical reaches of the
Colorado River between Glen Canyon Dam and Lake Mead.

Introduction
Approximately 25,000 river runners and hikers visit and camp along the corridor of the Colorado
River in Grand Canyon National Park every year (National Park Service, 2006). Because the banks are
dominated by bedrock cliffs, rocky talus, and boulder-covered debris fans (Howard and Dolan, 1981),
suitable locations for camping are limited in many places. Most campsites are located on sandbars
because these alluvial deposits are relatively flat and easily accessible from the river. Sandbars occur
intermittently along the shorelines, and campsites are abundant wherever sandbars are abundant. As the
number of visitors to the Colorado River corridor in Grand Canyon National Park (GCNP) has increased
since the mid-1960s, the distribution and quality of campsites have become an increasingly important
concern to river managers (U.S. Department of Interior, 1995; National Research Council, 1999;
Stewart and others, 2000; Bureau of Reclamation, 2001; National Park Service, 2006).

1

Because most campsites are located on sandbars, management of the two resources is intimately
linked. Sandbars are dynamic landforms deposited in eddies at times of high streamflow and high
suspended-sediment concentration. Sandbars may be eroded by streamflows that have low suspendedsediment concentration (Hazel and others, 1999), and sandbars also may be eroded by hillslope runoff
(Melis and others, 2004), wind deflation (Draut and Rubin, 2007), and human activity (Phillips and
others, 1986).
The completion of Glen Canyon Dam (GCD) in 1963 caused a 95 percent reduction in the
delivery of fine sediment to the Colorado River in Marble and Grand Canyons (Topping and others,
2000). High suspended-sediment streamflows are now rare, and sandbar erosion has generally outpaced
deposition (Rubin and others, 2002; Schmidt and others, 2004; Wright and others, 2005). Flow
regulation also reduced the magnitude and frequency of floods that reorganized the configuration of
sandbars and scoured riparian plants from the banks of the river. The number and size of plants
increased after 1965, colonizing formerly open sandbars that had been used as campsites (Turner and
Karpiscak, 1980; Kearsley and Ayers, 1996; Webb and others, 2002). The rate of increase in riparian
vegetation along the river margins has increased greatly since the early 1990s (Sankey, written
commun., 2013). Because of the combined impacts of sandbar erosion and invasion by riparian plants,
the number and size of campsites has decreased dramatically in the post-dam river (Kearsley and others,
1994; Kaplinski and others, 2005; Kaplinski and others, 2010).

Purpose and Scope
Improving the condition of campsites along the Colorado River in Grand Canyon National Park
is a priority management objective of the Glen Canyon Dam Adaptive Management Program
(GCDAMP). The GCDAMP Strategic Plan management objective 9.3 calls for an increase in the
“…size, quality, and distribution of camping beaches in critical and non-critical reaches…” of the
Colorado River between Glen Canyon Dam and Lake Mead (Bureau of Reclamation, 2001). To address
this objective, the U.S. Geological Survey, in cooperation with Northern Arizona University, conducted
an integrated program of sandbar and campsite monitoring that was aimed at understanding the effects
of Glen Canyon Dam operations on sandbars and campsites. This report describes the methods used to
monitor 37 sandbar campsites and the changes that occurred to those campsites between 1998 and 2012.
A companion report describes the monitoring program for the sandbar component of the study.

Study Area, Place Names, and Units
The study area is the 225-mi (362 km) segment of the Colorado River between Lees Ferry and
Diamond Creek, Arizona (fig. 1). The study area is subdivided into Marble Canyon, which extends
between Lees Ferry and the confluence with the Little Colorado River, and Grand Canyon, which
extends from the Little Colorado River to Diamond Creek. Locations along the river corridor are
referenced by convention as river mile (RM), which is distance, in miles, along the channel centerline
downstream of Lees Ferry (U.S. Geological Survey, 2013). Lees Ferry (RM 0) is located 15.5 mi (25
km) downstream from GCD, and 1 mi (1.6 km) upstream from the mouth of the Paria River and the
northeastern boundary of Grand Canyon National Park (fig. 1). The Little Colorado River confluence is
at RM 61.5, and Diamond Creek enters the Colorado River at RM 225.

2

Figure 1. Map showing campsite area study site locations along the Colorado River, Grand Canyon National Park,
Arizona.
Study sites are identified by RM and place name after Stevens (1990) and Belknap (2001). The
left and right sides of the Colorado River are determined as facing downstream. Different parts of the
Colorado River corridor in Marble and Grand Canyons have been classified as critical and non-critical
recreational segments, as defined by Kearsley and Warren (1993). Critical segments are stretches of the
river in which the number of available campsites is limited because of geomorphic setting, high demand
for nearby attraction sites, or other logistical factors. Non-critical segments are stretches in which
campsites are plentiful, resulting in little competition for most sites. Each campsite described in this
report is located in a critical or a noncritical recreational segment. The International System of Units is
used for all measures except for river mile, as noted above, and discharge, which is reported in cubic
feet per second (ft3/s).

3

Glen Canyon Dam Flows Releases during Study Period
Flows during the study period (fig. 2) followed the Modified Low Fluctuation Flow (MLFF)
preferred alternative of the 1996 Record of Decision on the Glen Canyon Dam Environmental Impact
statement (U.S. Department of Interior, 1996). The MLFF restricted minimum and maximum flows to
5,000 and 25,000 ft3/s, respectively, and included low-, medium-, and high-volume months, with low
flows during the late spring and late autumn, moderate flows in May and September, and high flows
during mid-summer and mid-winter. The daily fluctuation or range in flow was limited to 5,000 ft3/s
during low-volume months, 5,000 ft3/s during medium-volume months, and 8,000 ft3/s during highvolume months. In this report, flow releases regulated by the MLFF protocols are referred to as “normal
dam operations.”

Figure 2. Hydrograph showing the Colorado River at Lees Ferry (09380000), Arizona, 1998–2013. Survey trip
dates are shown as triangles. Note the daily and seasonal fluctuations in discharge volume, the May and
September 30,000 ft3/s powerplant capacity flows during the 2000 Low Steady Summer Flow (LSSF) experiment,
the November 2004 High Flow experiment, March 2008 High Flow experiment, and sustained high volume flows
during the summer of 2011.

4

During the study period, several flows were released that deviated from the MLFF operating
guidelines. These flows were either experiments (such as controlled floods), or the result of equalization
flows between Lake Powell and Lake Mead. Five high-flow releases occurred during the study period
and are of particular interest, as they resulted in elevated main stem discharge that inundated sandbars
and affected campsite areas. We refer to these flow events as “controlled floods.” The first two
controlled floods occurred in May and September 2000 as part of a flow experiment termed the Low
Summer Steady Flow Experiment (LSSF). The LSSF consisted of a 4-day power-plant capacity
controlled flood of 30,000 ft3/s that was released in May 2000, followed by 3 months of constant 8,000
ft3/s discharge, and then another 4-day power plant capacity controlled flood in September 2000. Two
controlled floods greater than powerplant capacity were released in November 2004 and March 2008.
Both of these controlled floods consisted of a 60-hour release of 42,000 ft3/s. In 2003, 2004, and 2005,
high-fluctuating flow experiments were conducted from January through March of each year. Flows
during these months consisted of diurnal fluctuations from 5,000 to 20,000 ft3/s. A non-experimental
flow that affected campsite area occurred from June 1 to August 31, 2011. We refer to these flow
releases as the “summer 2011 high-steady flows,” during which equalization flows governed by the
interim operating criteria averaged approximately 25,000 ft3/s, with no daily fluctuation (U.S.
Department of Interior, 2007).

Methods
Study Design and Site Selection
The objective of this study was to monitor changes in campsite areas associated with changing
sandbar condition and to relate these changes to operations of Glen Canyon Dam. The study was
designed as a companion component of a sandbar monitoring project in which the area and volume of
sandbars at selected monitoring sites is measured at least annually by topographic survey (Beus and
others, 1992; Kaplinski and others, 1995; Hazel and others, 1999; Hazel and others, 2010). Sandbars
monitored for change in campsite area are a subset of the sites measured for topographic change,
because not all sandbars are used as campsites. The original criteria for selection of the sandbar
monitoring sites were (1) distribution throughout the river corridor, (2) distribution of geomorphic
settings, (3) availability of historical data, (4) variation in recreation use intensity, and (5) variation in
vegetation cover (Beus and others, 1992). Some of the current sandbar and campsite area monitoring
sites were established by other researchers in the 1970s or 1980s (Howard and Dolan, 1981; Beus and
others, 1985; Schmidt and Graf, 1990). A total of 37 study sites are monitored for changes in campsite
area and provide the basis for this report (table 1). Thirty two sites were initially selected in 1998, and
an additional five sites were added in 2002. These campsites comprise approximately 10 percent of all
the sandbars identified as campsites by Grand Canyon National Park
(http://www.nps.gov/grca/parkmgmt/upload/2011CampsiteList.pdf).
The locations, informal camp names, and reach designation of the 37 sites are shown in table 1.
Sixteen of the study sites are in Marble Canyon, and 21 are in Grand Canyon (fig. 1). Sixteen sites are
located in critical reaches, and 21 are in non-critical reaches. No campsites upstream of Lees Ferry in
Glen Canyon (RM -15 to 0) or downstream of Diamond Creek (RM 225) were evaluated.

5

Table 1. Campsite monitoring study sites, along the Colorado River, Grand Canyon National Park, Arizona.
Mile1

Side

Name

Reach2

8.1

L

Jackass

NC

16.6

L

Hot Na Na

C

22.1

R

22 Mile

C

23.5

L

Lone Cedar

C

29.5

L

Silver Grotto

C

30.7

R

Sand Pile

C

31.9

R

South Canyon

C

35.0

L

Nautiloid

C

41.2

R

Buck Farm

NC

43.4

L

Anasazi Bridge

NC

44.5

L

Eminence

NC

45.0

L

Willy Taylor

NC

47.6

R

Lower Saddle

NC

50.1

R

Dino

NC

51.5

L

51 Mile

NC

55.9
62.9
81.7
84.6
87.7
91.7
93.8
104.4
119.4
122.8
123.2
137.7
139.6
145.9
167.1
172.2
183.3
183.3
194.6
202.3
213.3
220.1

R
R
L
R
L
R
L
R
R
R
L
L
R
L
L
L
R
L
L
R
L
R

Kwagunt Marsh
Crash
Grapevine
Clear Creek
Cremation
91 mile - above Trinity
Granite
104 Mile
119 Mile
122 Mile
Forster
Football Field
Fishtail
145 Mile
Lower National
172 Mile
183Left
183 Right
194 Mile
202 Mile
Pumpkin Springs
Middle 220 Mile

NC
NC
C
C
C
C
C
C
NC
NC
NC
C
C
C
NC
NC
NC
NC
NC
NC
NC
NC

1

Based on the river mile centerline (U.S. Geological Survey, 2013)

downstream from Lees Ferry (river mile 0)
2

C=Critical Reach, NC = Non-Critical Reach, as defined by Kearsley and Warren (1993).

6

Data Collection and Processing
There are no administrative definitions of what constitutes a campsite, and the National Park
Service (NPS) has few regulations that dictate campsite use. Aside from a few areas that are closed to
camping, river runners camp anywhere they choose. Visitors are, however, discouraged from camping
in previously undisturbed areas and clearing vegetation to establish new camping areas is not allowed.
Most river runners camp at sites that are repeatedly used throughout the river running season; some sites
are used nearly every night during the summer.
Because the purpose of this project is to track changes in the areas available for camping at
regularly used sites, we adopted a definition of “campsite area” similar to that used by the NPS in
previous studies (Kearsley and Warren, 1993). Campsite area is defined as any area of smooth substrate
(most commonly sand) with no more than an 8 degree slope and little or no vegetation. We used this
definition, but relaxed the slope criteria to include steeper areas near boat mooring locations where
campers typically establish their kitchens. Following this definition, a single campsite consists of any
number of smaller areas that meet the above criteria.
Campsite area was surveyed on 16 trips between 1998 and 2012 (fig. 2, table 2). Campsite
surveys were conducted using standard total-station survey techniques. Hazel and others (2008) reported
that individual points collected with total stations have horizontal accuracies that range from ±0.05 to
0.25 m and vertical accuracies that range from ±0.05 to 0.09 m, depending on the number of rod
extensions used. Approximately 90 percent of the points were collected at the standard rod height with
no extensions, where the accuracy is closer to the minimum level of 0.05 m, both horizontally and
vertically. Each campsite survey was completed by measuring topographic points that outlined the
perimeter of areas that meet the campsite area criteria, as well as collecting points to exclude areas
containing features within campsite areas such as trees, bushes, and rocks. The perimeter points were
then used to define polygons of campsite area (fig. 3). Slope was visually estimated in the field.
We did not include all campsite areas at every study site. Some campsites are large, and areas
outside a fixed outer perimeter were not monitored. The areas excluded from monitoring were located
far from mooring and kitchen locations and were typically at high elevations (greater than 45,000 ft3/s)
where current NPS regulations discourage camping (National Park Service, 2006). At other sites, some
of the campsite area was obstructed from view by the survey equipment and was not included. At every
site, the area for repeat monitoring was consistently defined. Survey crews used orthophotographs of
each site with previously surveyed areas plotted to ensure that previously excluded campsite areas were
not included in the mapping.
Because delineation of campsite area involves some unavoidable subjectivity, the question arises
as to whether or not campsite area mapping, using the methods described above, can be accurately
repeated. The repeatability of campsite area mapping was investigated by conducting surveys of the
same campsite (Nautiloid camp; RM 35.0; appendix A) on the same day by two separate crews during
the 1998 survey trip (fig. 3). Each crew established their own point locations to define the campsite area.
The total amount of campsite area measured by the two surveys was 751 and 723 m2, a 3.7 percent
difference in campsite area. Topographic and campsite area complexity varies between the study sites;
therefore, we conservatively estimate that the methods described here can detect changes in campsite
area greater than 10 percent for all sites. Additional repeat surveys will be conducted in the future to
better define the range of uncertainty associated with the mapping.

7

Table 2. Campsite survey trip data collected along the Colorado River, Grand Canyon National Park, Arizona,
1998–2012.
Trip date

Start date

End date

Discharge during surveys1

October 1998

10/10/1998

10/22/1998

10,000–18,000 ft3/s

October 1999

10/3/1999

10/14/1999

13,000–20,000 ft3/s

October 2000

10/15/2000

10/27/2000

7,000–12,500 ft3/s

October 2001

10/5/2001

10/18/2001

7,000–12,500 ft3/s

October 2002

9/20/2002

10/6/2002

5,500–10,000 ft3/s

May 2003

4/25/2003

5/12/2003

7,000–13,000 ft3/s

October 2003

9/20/2003

10/6/2003

5,500–10,000 ft3/s

May 2005

5/7/2005

5/22/2005

7,000–13,000 ft3/s

October 2006

10/7/2006

10/22/2006

7,000–13,000 ft3/s

October 2007

10/13/2007

10/29/2007

7,000–13,000 ft3/s

February 2008

2/2/2008

2/17/2008

8,500–13,500 ft3/s

April 2008

3/28/2008

4/12/2008

7,500–13,000 ft3/s

October 2008

10/11/2008

10/26/2008

12,100–12,600 ft3/s

October 2009

10/10/2009

10/25/2009

10,000–10,700 ft3/s

October 2011

10/5/2011

10/20/2011

15,000–16,300 ft3/s

October 2012

10/3/2012

10/18/2012

7,800–8,300 ft3/s

1

Flow levels from USGS gage (09380000) Colorado River at Lees Ferry, AZ.

The elevation of campsite areas relative to the river elevation is also important when river
runners decide where to camp because it is undesirable to carry equipment long distances or far upslope.
A campsite is also undesirable if it can be temporarily flooded. To account for fluctuating flows on
campsite areas, the campsite surveys were integrated with the topographic surveys so that changes to the
campsite area could be analyzed within specific ranges of discharge. Surveys were integrated by
constructing Digital Elevation Models (DEM) within the campsite area polygons. DEMs of the site
topography were constructed from the survey points using triangular irregular networks (TINs) by
Delaunay triangulation (McCullagh, 1998), and campsite area polygons were used to clip the DEM
boundary to produce a DEM within the campsite area polygons. The campsite area DEMs were used to
tabulate campsite area within six discrete discharge ranges, or zones. These zones were: (1) 10,000–
15,000 ft3/s, (2) 15,000–20,000 ft3/s, (3) 20,000–25,000 ft3/s, (4) 25,000–30,000 ft3/s, (5) 30,000–45,000
ft3/s, and (6) greater than 45,000 ft3/s. For each site, these discharge ranges were converted into
elevation ranges based on local stage-to-discharge relations computed by Hazel and others (2006). The
lowermost stage range (10,000–15,000 ft3/s) could not always be surveyed for all sites because
discharges often were greater than 10,000 ft3/s during the survey trips (table 2). Data for this zone is
included only in the tabulation of individual site data (appendix A).

8

Figure 3. Map showing repeat surveys of Nautiloid camp (RM 35.0) conducted on October 12, 1998 at 16:00 and
17:00 by independent survey crews. The total campsite area measured was 751 m2 (16:00) and 723 m2 (17:00),
which equates to a 3.7 percent difference in campsite area between surveys. Flow in main channel was from right
to left. Grand Canyon Monitoring and Research Center aerial photographs taken in May 2002 when discharge was
approximately 8,000 ft3/s.

9

Campsite area measurements were summarized by grouping the data into two zones that are of
greatest management interest. Normal dam operations generally consist of discharges with peaks rarely
exceeding 25,000 ft3/s (fig. 2). Discharges greater than this occur only during experimental floods
conducted to build sandbars (Schmidt and Grams, 2011). We reported “low stage-elevation” campsite
area as the sum of all campsite area in the zones between 15,000 and 25,000 ft3/s. These areas are most
affected by normal dam operations, are subjected to depositional and erosional processes, and are where
riparian vegetation has established only to a minor degree. The “high stage-elevation” campsite area
consists of all zones at elevations higher than 25,000 ft3/s. The high stage-elevation zone is situated
above the range of normal dam operations and is partially inundated only during controlled floods with
magnitudes typically between 40,000 and 45,000 ft3/s (fig. 2). Normal MLFF dam operations typically
involve release volumes that are higher in June, July, and August. During summer months, most
available campsite area is in the high stage-elevation zone. We also reported “total” campsite area as the
sum of the low and high stage-elevation zones. This sum includes all the campsite area consistently
measured at all of the study sites.
Complete data sets for each study site are given in appendix A. The appendix contains, for each
site, a site location map, a table of the campsite area data, time series plots for each stage elevation zone,
maps of each survey, and photographs of the study site at the beginning and end of the study period,
where available.
Time-series plots of the campsite area surveys show the changes to campsite area over time. A
summary of the campsite area data in all three stage elevation zones (total, high, and low) is presented
for all sites (fig. 4, table 3), sites in Marble and Grand Canyons (fig. 5, tables 4 and 5) to show
longitudinal changes with distance away from GCD, and within critical and non-critical recreational
segments (fig. 6, tables 6 and 7). Data were summarized by computing the mean and standard error of
the mean for the campsite area measured within each stage elevation zone for each survey. The
significance of the time series trends were evaluated by linear regression modeling (table 8).

10

Table 3. Mean campsite area for all sites in low, high, and total stage elevation zones along the Colorado River,
Grand Canyon National Park, Arizona, 1998–2012.
Low1

High2

Total3

Survey date

Mean

s.e4

Mean

s.e.4

Mean

s.e.4

n5

October 1998

185

45

487

70

623

75

30

October 1999

105

31

458

61

537

65

31

October 2000

327

69

414

54

741

90

30

October 2001

222

69

353

54

574

86

30

October 2002

162

35

272

38

434

48

37

May 2003

254

47

229

31

483

57

37

October 2003

248

47

231

33

479

54

37

May 2005

301

63

302

40

593

79

37

October 2006

120

28

218

30

337

44

37

October 2007

119

23

164

25

282

33

37

February 2008

121

26

180

27

301

42

37

April 2008

212

61

398

52

610

100

37

October 2008

123

30

265

35

388

45

37

October 2009

82

20

225

29

307

36

37

October 2011
October 2012

215
211

44
42

168
160

24
23

383
371

50
49

37
37

1

Low = campsite area measured between the 15,000 to 25,000 ft3/s stage elevation zone.

2

High = campsite area measured above the 25,000 ft3/s stage elevation zone.

3

Total = all campsite area measured above 15,000 ft3/s stage elevation zone.

4

s.e. = standard error of the mean.

5

n = number of sites.

11

Table 4. Mean campsite area for sites in low, high, and total stage elevation zones in Marble Canyon along the
Colorado River, Arizona, 1998–2012.
Low1
Survey date
October 1998
October 1999
October 2000
October 2001
October 2002
May 2003
October 2003
May 2005
October 2006
October 2007
February 2008
April 2008
October 2008
October 2009
October 2011
October 2012

Mean
221
96
365
335
144
230
203
305
118
119
133
357
171
100
214
248

High2
s.e.4
83
45
143
160
48
60
61
61
40
36
47
126
52
31
75
60

Mean
549
621
502
390
304
258
284
363
263
215
236
472
315
241
203
196

Total3
s.e.4
105
81
78
66
55
48
59
55
37
42
45
91
52
39
39
43

1

Mean
637
651
867
725
448
488
487
646
381
335
369
830
485
341
418
444

Low = campsite area measured between the 15,000 to 25,000 ft3/s stage elevation zone.

2

High = campsite area measured above the 25,000 ft3/s stage elevation zone.

3

Total = all campsite area measured above 15,000 ft3/s stage elevation zone.

4

s.e. = standard error of the mean.

5

n = number of sites.

12

s.e.4
114
81
165
161
56
78
71
80
58
54
75
198
64
44
71
73

n5
11
12
10
11
16
16
16
16
16
16
16
16
16
16
16
16

Table 5. Mean campsite area for sites in low, high, and total stage elevation zones in Grand Canyon along the
Colorado River, Grand Canyon National Park, Arizona, 1998–2012.
Low1
Survey date
October 1998
October 1999
October 2000
October 2001
October 2002
May 2003
October 2003
May 2005
October 2006
October 2007
February 2008
April 2008
October 2008
October 2009
October 2011
October 2012

Mean
164
111
308
156
176
272
283
298
121
118
112
101
87
69
216
182

High2
s.e.4
53
43
77
55
50
70
69
102
41
31
30
36
34
26
55
59

Mean
451
354
370
331
247
207
190
255
183
125
138
342
227
212
141
133

Total3
s.e.4
94
78
70
77
53
41
36
56
43
28
31
59
47
43
30
25

1

Mean
615
466
677
487
424
479
473
553
304
243
250
443
314
281
357
315

Low = campsite area measured between the 15,000 to 25,000 ft3/s stage elevation zone.

2

High = campsite area measured above the 25,000 ft3/s stage elevation zone.

3

Total = all campsite area measured above 15,000 ft3/s stage elevation zone.

4

s.e. = standard error of the mean.

5

n = number of sites.

13

s.e.4
100
91
107
96
75
82
80
126
65
41
46
77
58
53
70
66

n5
19
19
20
19
21
21
21
21
21
21
21
21
21
21
21
21

Table 6. Mean campsite area for sites in critical reaches in low, high, and total stage elevation zones along the
Colorado River, Grand Canyon National Park, Arizona, 1998–2012.
Low1
Survey date
October 1998
October 1999
October 2000
October 2001
October 2002
May 2003
October 2003
May 2005
October 2006
October 2007
February 2008
April 2008
October 2008
October 2009
October 2011
October 2012

Mean
185
127
234
128
173
244
222
292
100
93
107
187
164
102
225
242

High2
s.e.4
77
50
60
41
49
77
78
112
45
29
29
61
61
38
83
82

Mean
388
360
364
304
228
197
193
283
232
179
171
353
265
223
176
169

Total3
s.e.4
83
82
75
79
56
44
42
60
53
39
36
68
50
42
41
34

1

Mean
573
487
598
432
401
442
415
574
332
272
278
541
429
325
401
411

Low = campsite area measured between the 15,000 to 25,000 ft3/s stage elevation zone.

2

High = campsite area measured above the 25,000 ft3/s stage elevation zone.

3

Total = all campsite area measured above 15,000 ft3/s stage elevation zone.

4

s.e. = standard error of the mean.

5

n = number of sites.

14

s.e.4
89
80
96
76
63
86
79
129
70
41
45
91
68
52
84
84

n5
13
13
14
13
16
16
16
16
16
16
16
16
16
16
16
16

Table 7. Mean campsite area for sites in non-critical reaches in low, high, and total stage elevation zones along the
Colorado River, Grand Canyon National Park, Arizona, 1998–2012.
Low1
Survey date
October 1998
October 1999
October 2000
October 2001
October 2002
May 2003
October 2003
May 2005
October 2006
October 2007
February 2008
April 2008
October 2008
October 2009
October 2011
October 2012

Mean
185
90
408
293
154
262
268
308
135
138
132
231
92
67
208
187

High2
s.e.4
55
40
117
115
50
60
60
74
37
35
41
98
24
19
47
42

Mean
563
528
457
390
305
253
260
317
206
152
187
432
265
226
162
153

Total3
s.e.4
105
85
77
75
52
43
48
56
34
33
40
76
50
41
30
33

1

Mean
661
573
865
683
459
515
528
608
341
290
319
663
357
293
369
340

Low = campsite area measured between the 15,000 to 25,000 ft3/s stage elevation zone.

2

High = campsite area measured above the 25,000 ft3/s stage elevation zone.

3

Total = all campsite area measured above 15,000 ft3/s stage elevation zone.

4

s.e. = standard error of the mean.

5

n = number of sites.

15

s.e.4
115
97
142
136
71
77
74
102
59
51
67
163
60
49
61
60

n5

17
18
16
17
21
21
21
21
21
21
21
21
21
21
21
21

Table 8. Results of linear regression of mean campsite-area time series presented in tables 2 through 6, Grand
Canyon National Park, Arizona, 1998–2012.
Sites
all sites
all sites
all sites
Marble Canyon
Marble Canyon
Marble Canyon
Grand Canyon
Grand Canyon
Grand Canyon
critical
critical
critical
noncritical
noncritical
noncritical

Stage zone
low
high
total
low
high
total
low
high
total
low
high
total
low
high
total

F1
0.93
19.16
11.86
0.33
17.50
5.78
1.40
19.11
19.00
0.01
10.92
5.15
1.82
24.06
14.99

P2
0.351
0.001
0.004
0.574
0.001
0.031
0.256
0.001
0.001
0.920
0.005
0.040
0.198
0.000
0.002

(R2)3
0.06
0.58
0.46
0.02
0.56
0.29
0.09
0.58
0.58
0.00
0.44
0.27
0.12
0.63
0.52

1

F-ratio from single factor ANOVA with degrees of freedom = 1,14.

2

P is the significance of the F-ratio. Significance at the 95 percent level = 0.05.

3

R2 represents the percentage of variation explained by the fitted line, or “goodness of fit” of the line.

16

Figure 4. Time series plots showing mean campsite area for all sites along the Colorado River, Grand Canyon
National Park, Arizona. Standard error of the mean shown by error bars (A) Mean campsite area in total (greater
than 15,000 ft3/s) stage-elevation zone; (B) mean campsite area in high (greater than 25,000 ft3/s) stage-elevation
zone; (C) mean campsite area of low (15,000–25,000 ft3/s) stage-elevation zone. Refer to table 2 for data.
17

Figure 5. Time series plots showing mean campsite area for sites in Marble and Grand Canyons along the
Colorado River, Grand Canyon National Park, Arizona. Standard error of the mean shown by error bars. (A) Mean
campsite area in total (greater than 15,000 ft3/s) stage-elevation zone; (B) mean campsite area in high (greater
than 25,000 ft3/s) stage-elevation zone; (C) mean campsite area of low (15,000–25,000 ft3/s) stage-elevation zone.
Refer to tables 3 and 4 for data.
18

Figure 6. Time series plots showing mean campsite area for sites in critical and non-critical recreational segments
along the Colorado River, Grand Canyon National Park, Arizona. Standard error of the mean shown by error bars.
(A) Mean campsite area in total (greater than 15,000 ft3/s) stage-elevation zone; (B) mean campsite area in high
(greater than 25,000 ft3/s) stage-elevation zone; (C) mean campsite area of low (15,000–25,000 ft3/s) stageelevation zone. Refer to tables 5 and 6 for data.
19

Results and Conclusions
Campsite area decreased over the course of the study period, but varied strongly by elevation
zone and between surveys (figs. 4, 5, and 6). From 1998 to 2012, the mean total campsite area decreased
by an average of 36 percent and decreased at 29 of the 37 study sites. Regression modeling shows that
the decreasing trend in the total amount of campsite area (figs. 4A, 5A, and 6A) is significant (p<0.05;
table 8). Campsite area within the high stage-elevation zone shows a significant decreasing trend
(p<0.05; table 8) for all categories of sites (figs. 4B, 5B, and 6B), whereas there was no significant longterm trend in low stage-elevation campsite area (figs. 4C, 5C, and 6C). Campsite area decreased at all
37 study sites in the high stage-elevation zone by an average of 61 percent. In the low stage-elevation
zone, 21 sites increased in campsite area, 12 sites decreased in area, and 4 sites showed no change.
The effects of dam operations on campsite area are highlighted by examining changes between
surveys. In the high stage-elevation zone, campsite area increased for all categories (all sites, Marble
Canyon, Grand Canyon, critical and non-critical) after the controlled floods in November 2004 and
March 2008 (fig. 2). Increases in high stage-elevation campsite area result from sandbar deposition
during controlled floods (Grams and others, 2010; Hazel and others, 2010), where deposition builds
larger bars, fills gullies, and buries or removes vegetation. In contrast, high stage-elevation campsite
area decreased in the intervals between high flows when normal Record of Decision (ROD) flows did
not inundate the high-elevation zone. The two powerplant capacity (about 31,000 ft3/s) controlled floods
released during the 2000 LSSF experiment only partially inundated the high stage-elevation zone but
did not increase campsite area in this zone. The loss of campsite area during these intervals is likely due
to a combination of changes in sandbar slope and vegetation growth.
In the low stage-elevation zone, campsite area increases occurred after higher volume flows
within powerplant capacity as well as the two controlled floods greater than powerplant capacity. Low
stage-elevation campsite area increased after the two powerplant capacity controlled floods during the
2000 LSSF experiment, the high-fluctuating flows from January to March 2003, the 2004 and 2008
controlled floods, and the summer 2011 high-steady flows. Campsite area increased during these
intervals because flows partially or completely inundated the low stage-elevation zone, deposited
sediment (if sediment concentrations were high enough), and inhibited vegetation growth.
The campsite area surveys show a long term loss in campsite area. We conclude that dam
operations have not met the management objectives of the Glen Canyon Adaptive Management program
to increase the size of camping beaches in critical and non-critical reaches of the Colorado River
between Glen Canyon Dam and Lake Mead. However, a more thorough investigation is needed to better
quantify the mechanisms that cause campsite area change. We are currently conducting an analysis that
aims to correlate changes in campsite area with changes in topography and vegetation to provide a more
complete analysis of changes to campsite area along the Colorado River in Grand Canyon.

Acknowledgments
The authors wish to thank the many people who helped with data collection. Helen Fairley,
Carol Fritzinger, Tom Gushue, Keith Kohl, Rob Ross, Aaron Borling, Jeff Behan, Greg Sponenburgh,
Erik Kellerup, Laura Kennedy, Karen Koestner, Ryan Seumptewa, and Meagan Polino were
instrumental in collecting field data. Funding for this work was provided through the Glen Canyon Dam
Adaptive Management program of the Bureau of Reclamation.

20

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21

Kaplinski, M., Hazel, J.E., Jr., and Parnell, R., 2010, Colorado River Campsite Monitoring, 1998—
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22

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23

Appendix A. Campsite Area Data for Each Study Site
The appendix contains, for each site, a site location map, a table of the campsite area data, time
series plots for each stage elevation zone, maps of each survey, and photographs of the study site at the
beginning and end of the study period, where available.Appendix A in .PDF format can be downloaded
from http://pubs.usgs.gov/ofr/2014/1161.

24

Publishing support provided by the U.S. Geological Survey
Publishing Network, Tacoma Publishing Service Center
For more information concerning the research in this report, contact the
SBSC staff, Southwest Biological Science Center
U.S. Geological Survey
2255 N. Gemini Drive
Flagstaff, AZ 86001
http://sbsc.wr.usgs.gov/

Kaplinski and others—Colorado River Campsite Monitoring, Grand Canyon National Park, Arizona, 1998–2012—Open-File Report 2014–1161

ISSN 2331-1258 (online)
http://dx.doi.org/10.3133/ofr20141161