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OD1736 13 Existing management actions taken through W ater Year 2004, under the Record-of- Decision (ROD) failed to meet even the expectations contained in the Glen Canyon Dam EIS that, compared to the no action alternative, the preferred alternative would result in sand resources in the CRE increasing over time. The basic finding of the mass-balance project team is that downstream transport of new sand inputs occurs much more rapidly than was previously predicted by the Glen Canyon Dam EIS writing team (Rubin et aI., 2002). The rapid export of new sand inputs measured during 1999 through 2004 (Figure 1.2), from sediment-starved upstream reaches such as Marble Canyon, indicates that the ecosystem's sand supply does not become progressively enriched over multi-year periods, except during periods when monthly release volumes are at about 700,000 acre feet or lower. If most ROD dam operations prevent new sand inputs from accumulating within the river channel, then re-deposition of new sand inputs cannot occur during occasional controlled floods, termed "Beach/Habitat-Building Flows." Such periodic releases are intended to restore and maintain sand bars that have experienced erosion since dam closure. Suggested alternatives for better conserving new sand inputs include timing the release of bar-building floods to more closely follow significant periods of sand input from tributaries (this alternative was tested in November 2004, as discussed in a subsequent section on experimental flows). Another alternative is to schedule BHBF releases following periods when monthly ROD operations at Glen Canyon Dam consistently reflect below-average basin-hydrology conditions (8.23 million acre feet minimum release annual volumes). Water Ouality Monitoring - Downstream water quality monitoring has been aimed primarily at establishing a robust record of tributary and main stem temperature data under different flow conditions. More recent protocols attempt to characterize a variety of other parameters that provide information on the ecosystem function, such as dissolved oxygen. Temperature, conductivity, dissolved oxygen, and pH are monitored continuously at Glen Canyon Dam and at several locations on the Colorado River between the dam and Diamond Creek. Temperature is monitored at several other mainstem locations as well as on major tributaries. These data provide information on how these parameters change both in time and space throughout the CRE, aid in the calibration and validation of numerical models, and serve as baseline data for integration with the aquatic foodbase program. As an example, Figure 1.3 shows temperature data collected at Lees Ferry and at the Grand Canyon gage (Phantom Ranch) GCMRC FY2006 Annual Work Plan (Draft February 15,2005)