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APPENDIX B ANNOTATION FOR HISTORICAL PHOTO MATCHES USGS 32207 Dripping Springs (Photos 1,2) The original was taken on Sept. 61922. The approximate flow was 3100 cfs. The original is a good overview of the bedforms of the channel. The match that was made in June of 1996, USGS 32207 (1), shows the flow at approximately 17,000 cfs. This follow-up match is closer to the original photographs in flow rate and consequently illustrates the channel much better. Location: Mile 61.5 View: Upstream Matching Data: 9/4/96 5:10 P.M. Weather: Partly Cloudy and hot. Approximate flow: @ 2,100 cfs. Film: TMAX 100 Exposure: 1/60 sec. @ f/16 Camera Height: 150 cm. Print Data: PCER, RC, F in Dektol 1:2. 15 sec. ® f/22 Photographer: Susie Holman To Locate Matching Site: Just after passing the island below the rapid there is a cut bank on river left and a strong eddy. Pull in where possible. There is a nice camp here. Walking through the camp, find a spot to break through the vegetation and walk up the scree slope. The walk is a little steep. The site is along the second band of cliffs. Walk close to the cliff band for a safer walk. There is a small outcrop that gives a view up and down river. The site is marked with rebar, next to a knee high Mormon tea bush. Geomorphic/Vegetation Changes: • The island is now heavily vegetated. • The trees on the river left point bar are thicker and taller. • Vegetation on river right along sand and gravel bar is less dense now than in the original photograph. • Boulders exposed in river right above island. • Sand and gravel bars exposed: large, top center in right channel; small bar, center of right channel; large, bottom center of right channel. • The gravel and sand beach is exposed on river left as the right and left channels converge just above eddy. • The gravel and sand beach on river right is much larger, has become mo-te vegetated yet maintains same basic shape. • All cottonwoods and other trees much bigger and more in places along banks. • The thalweg near the convergence of two channels is on the left. The right 2/3rd of the channel is very shallow and cobbled.