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\\jI0'?, 9 Downstream Component IOWP Core-Ensemble Parameters (Temoerature, Conductivity, oH, DO. etc.) - Downstream integrated quality-of-water project (DIQWP) sampling has been aimed primarily at establishing a robust record of mains tern temperature data under different flow conditions, Much of the downstream water quality program has been undergoing redesign and reconsideration in light of the recent PEP report and the development of a new five-year plan for the Integrated Quality-of- Water Program presented to the TWG in 2002, In the mainstem, during the Low Steady Summer Flows of 2000, the highest temperatures in at least the last decade were observed in Grand Canyon, reaching nearly 20 deg, C at Diamond Creek. This reflected a warming of 10 deg, C above Glen Canyon Dam release temperatures, compared to a warming of5 deg. C during the high steady flows of 1997, showing a strong inverse correlation of in-stream warming with discharge level. Warming of over 7 deg. C above main channel river temperature occurred in some main channel near-shore environments; in backwater habitats, warming of over 12 deg C above river temperatures was observed, This near-shore warming was dependent on incident solar radiation, and little or no water velocity, IOWP Downstream Fine-Sediment Mass Balance - Results of sand-transport mass-balance calculations for the period offan 1999 through September 2000, show that sand loads passing the Grand Canyon gage, located 102 miles downstream of Glen Canyon Dam, exceeded total estimated tributary inputs; except during the period of June through August 2000 (Low Summer Steady Flow test), when dam operations were held constant at 8,000 cfs. Sand mass-balance data for October 2000 through November 2001, do show evidence of some accumulation of sand upstream of Phantom Ranch (river mile 87), in response to an approximate 1,000,000 metric ton input of sand from the Paria River in October 2000, in combination with relatively low-flow releases from Glen Canyon Dam throughout Water Year 2001. Additional sand inputs from the tributaries that occurred during September of Water Year 2002, also accumulated in the channel bed under the low-flow operations of September through December 2002, However, preliminary observations during January through March 2003, suggest that experimental fluctuating flows exported 2002 sand inputs from critical reaches above Phantom Ranch, GCMRC FY2005-2006 Draft Annual Work Plan (November 10,2003)