RECREATION - Revision history

Cellsworth at 22:31, 3 September 2026

2026-09-03T22:31:56Z

Cellsworth at 22:25, 3 September 2026

2026-09-03T22:25:55Z

Cellsworth at 22:22, 3 September 2026

2026-09-03T22:22:58Z

Cellsworth at 22:17, 3 September 2026

2026-09-03T22:17:45Z

Cellsworth at 20:36, 3 September 2026

2026-09-03T20:36:03Z

Cellsworth at 20:33, 3 September 2026

2026-09-03T20:33:32Z

Cellsworth at 20:26, 3 September 2026

2026-09-03T20:26:07Z

Cellsworth at 20:22, 3 September 2026

2026-09-03T20:22:22Z

Cellsworth at 20:15, 3 September 2026

2026-09-03T20:15:31Z

Cellsworth at 20:10, 3 September 2026

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 The Colorado River Runners Oral History Project is unparalleled within river running communities: though there are many regional organizations, no others have undertaken a project of this scope. GCRG unofficially began collecting oral history interviews in 1990 at “Woman of the River” Georgie White Clark’s 80th birthday party. Since that time, GCRG’s oral history project has produced nearly 100 interviews. Those interviews continue to serve as the centerpiece for each issue of our publication, the [http://www.gcrg.org/bqr.php '''Boatman’s Quarterly Review'''].
-== [http://www.gcrg.org/advocacy_aab.php Adopt a Beach Project] ==
+== [https://www.gcrg.org/adoptabeach Adopt a Beach Project] ==
-Implemented in 1996 after the first historic “Flood Flow,” Adopt-a-Beach is a “watch dog” program that allows volunteer guides to keep close tabs on changes to the recreational resource that we depend upon – camping beaches in Grand Canyon.  To be specific, this long term photo-matching, beach monitoring effort documents changes in sand deposition on camping beaches along the Colorado River resulting from Glen Canyon Dam flows.  The results are disseminated to strategic river managers including Grand Canyon National Park, the Adaptive Management Program, and the Grand Canyon Monitoring & Research Center.  Adopt-a-Beach is a fabulous example of a stewardship in action as we endeavor to “take care of our own back yard.”  Please check out our extensive photo gallery as well as the Executive Summaries of past AAB reports.  Full Reports are available upon request.  And contact gcrg@infomagic.net if you’d like to volunteer! [http://www.gcrg.org/advocacy_aab.php]
+Implemented in 1996 after the first historic “Flood Flow,” Adopt-a-Beach is a “watch dog” program that allows volunteer guides to keep close tabs on changes to the recreational resource that we depend upon – camping beaches in Grand Canyon.  To be specific, this long term photo-matching, beach monitoring effort documents changes in sand deposition on camping beaches along the Colorado River resulting from Glen Canyon Dam flows.  Adopt-a-Beach is a fabulous example of a stewardship in action as we endeavor to “take care of our own back yard.”
-*[http://www.gcrg.org/aab/exec_summary_09.pdf 2009 Executive Summary]
+Please check out our extensive PHOTO GALLERY as well as the Adopt-a-Beach reports posted below. And contact info@gcrg.org if you’d like to volunteer!
-*[http://www.gcrg.org/aab/exec_summary_08.pdf 2008 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_06.html 2006-2007 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_05.html 2005 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_04.html 2004 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_03.html 2003 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_02.html 2002 Executive Summary]
-*[http://www.gcrg.org/aab/exec_summary_00_01.html 2000-2001 Executive Summary]
-*[http://www.gcrg.org/bqr/17-4/aab.html Executive Summary of Results for Years 1996–2003]
+Increased erosion to beaches in the post-dam era and guides' concerns for better resource management led to this volunteer monitoring effort. During a commercial river season, guides document a sample set of about 40 beaches by using 35-mm, disposable cameras. Photographs are taken from designated locations overlooking their adopted beach and a data sheet is filled out every time the guides go down river. Results are analyzed by our principal investigator, and conclusions are presented to pertinent resource managers and the public.
-*[https://www.gcmrc.gov/library/reports/cultural/Recreation/01WRGR0007/AAB%202001%20report.pdf Long Term Monitoring of Camping Beaches in Grand Canyon: A Summary of Results from 1996 – 2001 Annual Report of Repeat Photography By Grand Canyon River Guides, Inc. (Adopt-A-Beach Program)  ]
-*[https://www.gcmrc.gov/library/reports/cultural/Recreation/01WRGR0007/AAB%202000.pdf Changes to Grand Canyon Camping Beaches, Year 2000: Annual Report of Repeat Photography by Grand Canyon River Guides, Inc. (Adopt-a-Beach Program) ]
+Adopt-a-Beach is a fantastic example of citizen science in action!  It’s a great way to involve your passengers and educate about a beach change in a dam managed environment!  [https://www.gcrg.org/adoptabeach]
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 Because use is capped and demand still exceeds it, the number of people on the river tells us almost nothing about whether a given flow regime made trips better or worse, the boats go out regardless of the water year. To learn whether flow matters to boaters, researchers have had to ask them directly.
-Two independent surveys, run 15 years apart ([https://gcdamp.com/images_gcdamp_com/3/3d/1987_Bishop_GCDam_releases_downstream_rec_analysis_user_pref.pdf Bishop et al. 1987] and [http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf Stewart et al. 2000), asked boaters to rate the importance of 24 trip features. Both times, the same five features came out on top, in the same order: being in the unique setting of Grand Canyon, being in a natural setting generally, stopping at side canyons and creeks, hiking those side canyons, and observing flora, fauna, and geology. Notably, rapids themselves were not among the top five, although the size and challenge of rapids does show up strongly in later satisfaction work.
+Two independent surveys, run 15 years apart ([https://gcdamp.com/images_gcdamp_com/3/3d/1987_Bishop_GCDam_releases_downstream_rec_analysis_user_pref.pdf Bishop et al. 1987] and [http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf Stewart et al. 2000)], asked boaters to rate the importance of 24 trip features. Both times, the same five features came out on top, in the same order: being in the unique setting of Grand Canyon, being in a natural setting generally, stopping at side canyons and creeks, hiking those side canyons, and observing flora, fauna, and geology. Notably, rapids themselves were not among the top five, although the size and challenge of rapids does show up strongly in later satisfaction work.
 Flow connects to these attributes mainly through time. Faster flows mean less time spent rowing or motoring and more time left in the day for the things boaters said they value most. Trip-diary work by Roberts and Bieri during the 2000 low summer steady flow experiment found boaters had about 7 hours a day for swimming, hiking, and visiting sites at flows around 19,000 cfs, versus only 3.5 hours at the 8,000 cfs steady flow. Satisfaction and stated economic value both peak in a middle flow band, roughly 20,000–28,000 cfs, and fall off at both extremes: too little water means slow travel and exposed hazards, too much means intensified rapids and shrinking camp beaches.
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 Additionally, Stewart et al.’s (2000) follow-up of the Bishop et al. (1987) study found that angler’s did not identify river level fluctuations, at least under the MLFF operating regime, as an issue. Based on information from Stewart et al (2000) and Bishop et al. (1987), '''any flow fluctuation below 10,000 cfs/day should be treated the same as a steady flow release'''.
-*[http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf The Stewart Report: Preferences of Recreation User Groups of the Colorado River in Grand Canyon. 2000]
+*[http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf The 2000 Stewart Report: Preferences of Recreation User Groups of the Colorado River in Grand Canyon.]
-*[http://www.swrcb.ca.gov/water_issues/programs/ocean/cwa316/docs/cwa316may2010/comments041310/bishop_etal.pdf The Bishop Study: Grand Canyon Recreation and Glen Canyon Dam Operations: An Economic Evaluation. 1987. pg 407-436 ]
+*[http://www.swrcb.ca.gov/water_issues/programs/ocean/cwa316/docs/cwa316may2010/comments041310/bishop_etal.pdf The 1987 Bishop Study: Grand Canyon Recreation and Glen Canyon Dam Operations: An Economic Evaluation. pg 407-436 ]
-*[[File:1987 Bishop GCDam releases downstream rec analysis user pref.pdf| The Bishop Study: Glen Canyon Dam Releases and Down Stream Recreation: An Analysis of User Preferences and Economic Values. 1987. Report to GCES. 398 pgs. ]]
+*[[Media:1987 Bishop GCDam releases downstream rec analysis user pref.pdf| The 1987 Bishop Study: Glen Canyon Dam Releases and Down Stream Recreation: An Analysis of User Preferences and Economic Values.  Report to GCES. 398 pgs. ]]
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 Because use is capped and demand still exceeds it, the number of people on the river tells us almost nothing about whether a given flow regime made trips better or worse, the boats go out regardless of the water year. To learn whether flow matters to boaters, researchers have had to ask them directly.
-Two independent surveys, run 15 years apart (Bishop et al., mid-1980s; Stewart et al., 1998–99), asked boaters to rate the importance of 24 trip features. Both times, the same five features came out on top, in the same order: being in the unique setting of Grand Canyon, being in a natural setting generally, stopping at side canyons and creeks, hiking those side canyons, and observing flora, fauna, and geology. Notably, rapids themselves were not among the top five, although the size and challenge of rapids does show up strongly in later satisfaction work.
+Two independent surveys, run 15 years apart ([https://gcdamp.com/images_gcdamp_com/3/3d/1987_Bishop_GCDam_releases_downstream_rec_analysis_user_pref.pdf Bishop et al. 1987] and [http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf Stewart et al. 2000), asked boaters to rate the importance of 24 trip features. Both times, the same five features came out on top, in the same order: being in the unique setting of Grand Canyon, being in a natural setting generally, stopping at side canyons and creeks, hiking those side canyons, and observing flora, fauna, and geology. Notably, rapids themselves were not among the top five, although the size and challenge of rapids does show up strongly in later satisfaction work.
 Flow connects to these attributes mainly through time. Faster flows mean less time spent rowing or motoring and more time left in the day for the things boaters said they value most. Trip-diary work by Roberts and Bieri during the 2000 low summer steady flow experiment found boaters had about 7 hours a day for swimming, hiking, and visiting sites at flows around 19,000 cfs, versus only 3.5 hours at the 8,000 cfs steady flow. Satisfaction and stated economic value both peak in a middle flow band, roughly 20,000–28,000 cfs, and fall off at both extremes: too little water means slow travel and exposed hazards, too much means intensified rapids and shrinking camp beaches.
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 The other flow-sensitive attribute is campsite area, the sandy beaches boaters camp, cook, and hike from. Long-term monitoring (Kearsley and colleagues in the 1990s; Kaplinski and colleagues through the 2000s) has tracked a persistent decline: total campable area above the 25,000 cfs stage fell an estimated 44% between 1973 and 1991, and a further 55% between 1998 and 2003 alone. Because beach size directly affects crowding, camp choice, and the wilderness feel of a trip, this decline bears on GCDAMP's recreation objectives.
-The economics literature has gone a step further and asked boaters what they'd pay for different hypothetical flow scenarios, using a "would you pay $X more than you did" question format. This traces out something like a demand curve and lets researchers estimate consumer surplus, the federally recommended way to value recreation benefits, and a genuinely different quantity from regional spending (which barely moves with flow, since use is capped). The 1985 Bishop study and a 2017 replication by Neher, Duffield, Bair, and colleagues both found the same inverted-U shape: private boaters' trip value rising from roughly $110 at 5,000 cfs to a peak near $630 around 28,000 cfs, then declining at 40,000 cfs.
+The economics literature has gone a step further and asked boaters what they'd pay for different hypothetical flow scenarios, using a "would you pay $X more than you did" question format. This traces out something like a demand curve and lets researchers estimate consumer surplus, the federally recommended way to value recreation benefits, and a genuinely different quantity from regional spending (which barely moves with flow, since use is capped). [https://gcdamp.com/images_gcdamp_com/3/3d/1987_Bishop_GCDam_releases_downstream_rec_analysis_user_pref.pdf The 1987 Bishop study] and a [https://gcdamp.com/images_gcdamp_com/8/82/Neher_2017_Testing_limits_temporal_stability_GC_boaters_pay_values.pdf 2017 replication by Neher, Duffield, Bair, and colleagues] both found the same inverted-U shape: private boaters' trip value rising from roughly $110 at 5,000 cfs to a peak near $630 around 28,000 cfs, then declining at 40,000 cfs.
 What makes the 2017 study unusual is what it tested: whether those 1985 values still held 30 years later, the longest such comparison in the willingness-to-pay literature. The two boater cohorts had experienced very different rivers (an average flow of 26,000 cfs for the 1985 sample versus about 12,000 cfs for the 2015 sample), yet their adjusted willingness-to-pay values for the same four hypothetical flow scenarios were statistically indistinguishable. The ranking of scenarios was identical across the 30-year gap. The one caveat the authors flagged is that while the mean values held up, the underlying shape of how boaters respond to bid levels may have shifted somewhat once the data are corrected for differing survey designs, a technical nuance, but one worth stakeholders knowing about, since it means "stable values" is a more solid finding than "unchanging boater psychology."

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 [[File:CampsiteArea 1998 2014.jpg|center|600px]]
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 |style="color:#000;"|
 *[https://www.nps.gov/grca/learn/management/upload/CRMPIF_s.pdf 2006 Colorado River Management Plan]
 *[http://gcpba.org/ Grand Canyon Private Boaters Association (GCPBA) Page]
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 *[https://www.gcmrc.gov/gis/silveratlas1.aspx GCMRC Campsite Atlas] (requires microsoft silverlight plug-in)
 *[https://www.gcmrc.gov/gis/camptour/index.html GCMRC Campsite photo tour]
 *[http://gcdamp.com/index.php?title=GCDAMP_Sediment Sediment Page]
 *[http://gcdamp.com/index.php?title=Riparian_Vegetation Vegetation Page]

← Older revision		Revision as of 20:36, 3 September 2026
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	*The threshold of 8 degrees is used to describe the approximate threshold for areas considered flat enough to use for camping (Kearsley and others, 1994; Hadley and others, 2018).		*The threshold of 8 degrees is used to describe the approximate threshold for areas considered flat enough to use for camping (Kearsley and others, 1994; Hadley and others, 2018).
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−	~~! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Willingness to pay studies </h2>~~
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−	*[https://www.usgs.gov/data/grand-canyon-whitewater-boater-data-convergent-validity-between-willingness-pay-elicitation Neher et al., 2018, Exploring convergent validity between willingness to pay elicitation methods—An application to Grand Canyon whitewater boaters: Journal of Environmental Planning and Management]
−	*[[Media:Neher 2017 Testing limits temporal stability GC boaters pay values.pdf\| Neher et al., 2017, Testing the limits of temporal stability—Willingness to pay values among Grand Canyon whitewater boaters across decades. Water Resource Research]]
−	*[https://ltempeis.anl.gov/documents/docs/Colorado_River_Value_Study.pdf Duffield et al. 2016. Colorado River Total Value Study]
−	*[http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf The Stewart Report: Preferences of Recreation User Groups of the Colorado River in Grand Canyon. 2000]
−	*[http://www.swrcb.ca.gov/water_issues/programs/ocean/cwa316/docs/cwa316may2010/comments041310/bishop_etal.pdf The Bishop Study: Grand Canyon Recreation and Glen Canyon Dam Operations: An Economic Evaluation. 1987. pg 407-436 ]
−	*[[Media:1987 Bishop GCDam releases downstream rec analysis user pref.pdf\| The Bishop Study: Glen Canyon Dam Releases and Down Stream Recreation: An Analysis of User Preferences and Economic Values. 1987. Report to GCES. 398 pgs. ]]

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 *[https://www.usgs.gov/data/grand-canyon-whitewater-boater-data-convergent-validity-between-willingness-pay-elicitation Neher et al., 2018, Exploring convergent validity between willingness to pay elicitation methods—An application to Grand Canyon whitewater boaters: Journal of Environmental Planning and Management]
 *[[Media:Neher 2017 Testing limits temporal stability GC boaters pay values.pdf| Neher et al., 2017, Testing the limits of temporal stability—Willingness to pay values among Grand Canyon whitewater boaters across decades. Water Resource Research]]
 *[http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf The Stewart Report: Preferences of Recreation User Groups of the Colorado River in Grand Canyon. 2000]
 *[http://www.swrcb.ca.gov/water_issues/programs/ocean/cwa316/docs/cwa316may2010/comments041310/bishop_etal.pdf The Bishop Study: Grand Canyon Recreation and Glen Canyon Dam Operations: An Economic Evaluation. 1987. pg 407-436 ]

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 *The threshold of 8 degrees is used to describe the approximate threshold for areas considered flat enough to use for camping (Kearsley and others, 1994; Hadley and others, 2018).
 |}
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 *[https://doi.org/10.1002/rra.3349 Hadley et al., 2018, Quantifying geomorphic and vegetation change at sandbar campsites in response to flow regulation and controlled floods, Grand Canyon National Park, Arizona: River Research  and Applications]
 *[https://doi.org/10.3133/sir20175096 Hadley et al., 2018, Geomorphology and vegetation change at Colorado River campsites, Marble and Grand Canyons, Arizona: U.S. Geological Survey Report ] [https://doi.org/10.5066/F7FJ2FQQ data]
 *[[Media:20171219 GCPBA HFE comments.pdf| Grand Canyon Private Boater's Association (GCPBA) letter requesting slower downramp rates following the Fall 2016 High flow experiment.]]
 *[[Media:GaylordTWG0416.pdf| Life Before AMWG]], by Gaylord Staveley, April 19, 2016
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 *[http://www.riversimulator.org/Resources/GCMRC/Recreation/Stewart2000.pdf Stewart et al. 2000. Preferences of Recreation User Groups of the Colorado River in Grand Canyon. ]
 *[https://www.usbr.gov/uc/progact/amp/twg/1999-10-22-twg-meeting/Attach_12.pdf Behan, J. 1999, Recreation in the Colorado River Ecosystem, Grand Canyon, white paper to GCMRC]
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