dopt-a-Beach is soon to celebrate ten years of all-volunteer, repeat photography of Grand Canyon camping beaches. Dedicated guide effort year after year has made this program possible to succeed in performing its primary functions: amass information about the status of Canyon Beaches from guides and other river runners who regularly see them, provide visual and analytic documentation of the beaches, and represent recreational interests to resource managers such as those at the Glen Canyon Dam Adaptive Management Program (amp). The opportunity presents itself for guides to interpret the downstream effects of Glen Canyon Dam-and, by extension, all dams— to rafters from other parts of the country and the world who are not able to see the changes over time. With the release last November of the second Beach/Habitat-Building Flow (bhbf) since the Spring of 1996, the Adopt-a-Beach photo archive and analyses have provided an important insider’s look at nine years of changing beaches.

The State of the Colorado River Ecosystem in Grand Canyon, (the “score Report”) recently published, details over ten years of research by the usgs’s Grand Canyon Monitoring and Research Center. Continuing efforts by the amp to manage Glen Canyon Dam so as to “increase the size, quality, and distribution of camping beaches” have not succeeded. Beach size remains roughly the same or decreasing. Adopt-a-Beach program records are consistent with this appraisal. A copy of the score Report is available online at http://www.gcmrc.gov/products/score/2005/ score.htm.

Adopt-a-Beach analysis for the 2004 season revealed no significant changes in beach conditions with the comments regarding the encroaching vegetation, mostly tamarisk, but also including arrowweed and camelthorn, were noted for the 2004 season, up from seven in 2003. Loss of campsite area due to vegetation encroachment has been considered problematic for years. Efforts to quantify area loss due to vegetation are underway. Adopt-a-Beach photo locations show the growth of tamarisk and other vegetation that may stabilize beach fronts but also reduce available camp space.

Beach sizes were remarkably consistent throughout the 2004 Summer season. There were no significantly visible or reported increases in beach size. An overwhelming 92 percent of summer change records indicate that the beaches remained the same. Small deposits made during the Summer fluctuations can be seen in photos taken after flows reduced to 5,000–10,000 cfs in September. Such deposits are short-lived and could be seen as a thin layer on rocks near camp mooring areas (see 23 Mile figures). The camp at Upper National (Mile 166.4, river left) showed progressive cut bank retreat throughout the season, removing the small deposit made by the Winter flow. Small variations like this are seen in the photo record, but have no substantial impact except in aggregate, resulting in the continued degradation of any accumulated sediment.

Winter High Fluctuating Flows (whff) of 5,000– 20,000 cfs continued from January through March 2004. Guides commented on the “spongy” nature of sand deposited during the whff. Most camps (28 of forty) revealed no change over the Winter. Silver Grotto was the only beach to have any appreciable visible change over the Winter season, and it showed a decrease over the Summer season to remain, at season’s end, at lower levels than before the 1996 bhbf of 45,000cfs.

Comparing results of the 2004 Winter season change to the 2003 Winter season change does not show encouraging signs. Overall, beaches at the start of the 2004 Summer season showed less change as a result of the whff as compared to the start of the 2003 season. When compared by reach, over 75 percent (eleven of fourteen) of beaches in Marble Canyon remained the same over the 2004 Winter; only about 36 percent (four of eleven) remained the same over the 2003 Winter. There were, however six fewer beaches in total showing an increase after the 2004 Winter compared to after the 2003 season. This may be the result of a sediment deprived system finding an equilibrium in response to the whff. Although the reasons for the changing response to the whff are unclear, it would no longer seem prudent to recommend continuing such flows under similar circumstances in the future in the name of conserving beach sediments.

Continued winnowing of the 1996 bhbf deposits can be seen in comparing end-of season photos with pre-bhbf photos. Only one-fifth of beaches remain larger than in March of 1996, compared to over one-quarter of beaches at the end of the 2003 season. Pre-1996 bhbf conditions persist one-third of the beaches, while more than one-fifth of beaches show a decrease. While certain beaches are becoming more difficult to evaluate as vegetation encroaches (Tathatso and Hance, for example), it is clear in most cases that continued high fluctuating flow regimes are detrimental to the beach deposits.

As our beaches are obviously shrinking, I would give an important reminder to all guides: camping above the Old High Water Zone should not be allowed. Our rafting clients often seek out the most comfortable camping spots, which may in some instances be in the fragile zones away from shore. Pressure on the resource will undoubtedly increase; a word beforehand may help ease some of this strain.

Adopt-a-Beach for 2005

The bhbf that took place last November was the single most important experiment for beaches in over nine years. After reaching the predetermined sediment trigger from the Paria, a flow similar to the bhbf in 1996 streamed through the Canyon. Shortened in duration and slightly lower in flow, this bhbf was successful in depositing new beach sediments in primarily Marble Canyon. The 2005 season Adopt-a-Beach packets are nearly all returned and results from the program on the first year after this new bhbf will be forthcoming next year.

The Adopt-a-Beach program would not continue without the support of all guides and river-going adopters who make this possible. Adopting a beach is one way of becoming more active in the management of the Canyon and can be an opportunity to interpret the dam-influenced environment for those who choose a Grand Canyon river trip. A big thank you to the individual contributors to Adopt-a-Beach and especially to the Grand Canyon Conservation Fund. This fund is established by our outfitters and was essential for the 2004 Adopt-a-Beach program.

Joe Pollock