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Obiectives: I. River Geometry Monitoring: Determine short term and long term change in river cross sections at key locations and the relationship of this change to spring runoff and summer/fall storm events. 2, Cobble Bar Monitoring: Determine short term and long term change in cobble bar characteristics in response to spring runoff and summer/fall storm events. 3. Backwater Perturbation Monitoring: Monitor effect of spring runoff and summer/fall storm events on sediment accumulation in backwaters and backwater depth. Methods: I. River Geometry Monitoring: The 14 cross-sections identified in 1999 as part of the long term monitoring plan will be surveyed pre- and post-runoff for analysis of annual change and compared to previous surveys to determine trends. Analysis of the change in cross-section geometry and substrate in relation to hydrographic conditions will be completed to monitor response of the system to flow recommendations, 2. Suspended Sediment Analysis: Continuous turbidity monitors are installed at Shiprock, New Mexico and Montezuma Creek Bridge, Utah. The data will be used to qualitatively assess sediment transport in relation to the flow regime, in addition to identification of storm events. 3. Cobble Bar Monitoring: Maintenance of cobble bars with open interstitial space has been determined to be important for spawning of Colorado Pikeminnow. Four sites (RM 173,7, 168.4, 132, 131) have been identified in the San Juan River as having characteristics suitable for spawning. These sites have been monitored since 1995, The results of the surveys at this site were used as part of the basis of the flow recommendation at 8,000 cfs. To verify or adjust this recommendation, these sites will continue to be monitored per the long range monitoring plan. Topographic surveys will be completed for each of the sites utilizing total station or gps survey equipment with control provided by the established bench marks at each site. Surveys will be completed as soon as practical after spring runoff, usually during the end of July or early August. The same area will be surveyed each year to allow comparison to previous years. At the same time, the structure of the bar will be assessed by completing point counts of the surface bed material (n=200 per sample or more) at each bar. Particles will be selected by the point count method over the full extent of the bar within the survey boundary. Size is determined by placing the rocks through a square hole in an aluminum plate, cut to represent an equivalent screen size from I cm through 10 cm at I cm increments, then 2 cm increments through 20 cm, Those larger than 20 cm are recorded as greater than 20 em. Interstitial material smaller than I cm is not recorded. 21 I I I I \ ~ I I I \ I I I I I I ~ I E