he Adaptive Management Program for Canyon Dam moves into its 10th year. There have been some remarkable events in the past year. Here’s a glimpse of some of it. Please read on! August, 2004...we were in the most severe five year drought since Spanish conquistadores first gazed into the depths of Grand Canyon (1540s). Lake Powell had dropped to its lowest level since it was first filling in the late 1960s. Western Area Power Administration gave us the news that the dam could lose generating capacity in 2006 if the drought continued. Power revenues that fill the coffers of the Colorado River Basin Fund would dry up, which would impact the funding source for the amp, operation and maintenance of the dam and electrical transmission system, Salinity Control Program, irrigation projects, and other environmental programs in the basin.

The Adaptive Management Work Group made several notable recommendations at the August 2004 meeting. We prioritized our concerns to a few main areas, including: Humpback chub, archeological sites and sand bars. The need for prioritization arose from the realization that the program cannot cover the entire suite of management objectives outlined in the strategic plan given the level of funding for the program. So, a prioritization of the program components was undertaken. Unfortunately, several aspects of the program that are important to our cause, such as the recreation resources, were found at the bottom of the list when the exercise was complete. Most amwg members concur that abundant sandbars are a critical component of ecosystem health, whether for sufficient recreational camping beaches, renewal of sand to in fill and protect eroding archeological sites, or for reforming backwater habitat for rearing of endangered humpback chub.

We also made three recommendations for experimental actions during the 2005 water year (October 1, 2004–September 31, 2005.) First, we recommended a High Test Flow (htf) above power plant capacity should be conducted in November 2004 upon reaching a sediment input trigger from the Paria River by the end of October. Reaching a consensus agreement to conduct a fall high flow test is an amazing accomplishment and something that gcrg has been working towards for several years. As of last year, cries of “It will never happen!” were heard from the water and power interests, as floods above power plant capacity in the fall violate certain aspects of the “Law of the River”. However, scientific facts, economics, and some political maneuvering won the day and the recommendation recommended another year of Trout Suppression Flows (tsf), 5000–20,000 cfs daily fluctuations for January 1 to April 7. In order to get a fall flood flow recommendation, it was a political necessity to agree to these flows, as these flows are very beneficial for hydropower, especially during peak power demand in mid winter. Thirdly, we recommended another year of “mechanical removal” of non-native fishes near the mouth of the lcr.

For the first time since 2001, the Paria River input enough sediment to trigger the high flow release and the experiment was on. The experiment lasted 90 hours, reached a maximum release of 41,000 cfs and had a gentle up ramp and down ramp from the 8000 cfs constant flows before and after the event. Initial assessments showed that the htf deposited new sand bars throughout the system, similar to those observed in 1996. Sandbars in upper Marble Canyon (rm 0–41), the most “scoured” reach, did very well, but results were mixed in lower Marble Canyon (rm 41–65). The experiment proved that tributary inputs can be “managed” with high flow events and that, perhaps, sand bars can be sustained. Scientific studies done on various aspects of the river ecosystem were presented at the October 25–27 gcmrc Science Symposium in Tempe and are contained in a recent compilation available on the web (http://www.gcmrc.gov/news_info/outreach/symposiums/ 2005/sym_2005.htm). Another report is available through the gcmrc-The score Report-that summarizes ten plus years of monitoring and research leading up to the 2004 high flow test (http://www.gcmrc.gov/ products/score/2005/score.htm)

Many of us predicted that the tsf following the htf would largely erode new sand deposits. Initial results from the sediment scientists show that erosion rates following the 2004 high flow were similar to those observed in 1996-the newly built sand bars did erode. It is clear to us that high flow events are needed at a greater frequency (2–3 years) in order to rebuild eroded sand bars, increase camping area, possibly slow the erosion of archeological sites, form near shore habitats for native fish, and restore disturbance events to the system. Individual flood events are not a one time “fix” and need to be conducted whenever there’s enough sediment. The 2004 event proved to us that these flood events need to be part of the operations and not just as experiments and we will continue to work towards this goal.

At the August 2005 amwg meeting, we struggled with budget woes caused by poor bookkeeping by the Feds. We suspended the tsf and the possibility of another htf in 2006. We want to see how the tsf compares to normal Record of Decision operations and need final results on the htf before knowing how best to plan for and conduct the next beach building flow.

Upcoming issues include developing a recreation resources monitoring program, future experimental flow plans, developing budgets, etc. Gcmrc recently conducted a review of the recreation resources monitoring program (also see score Report chapters on this subject) and we will be involved in vetting that report through the amp and (hopefully) working in better cooperation with the Grand Canyon National Park on these issues. Future flow experiments are also being considered that include:
1) more high flows;
2) seasonally adjusted steady flows;
3) )more high fluctuations;
4) mechanical removal of trout and much more.

Andre Potochnik, Matt Kaplinski, John O’Brien