and aerial photographic interpretations were also used in the analysis 

 of each site. 



Geology and Geomorpho I ogy . Using topographic maps, stereo aerial photo- 

 graphy, and surficial geology maps, a brief analysis of each drainage basin 

 was made to evaluate the geomorpho I ogy of the river val ley, the river ter- 

 races, and the present and past regime of the river. The morphological fea- 

 tures pertaining to the general area around the material site were verified 

 in the field. 



Hydrology . The U.S. Geological Survey Water Resources Records were 

 reviewed for flow measurements within a study site's drainage basin. Where 

 flow measurements were representative, various key discharges with the 

 respective stages were estimated and documented. In the field, evidences 

 of floods were investigated. Where sufficient data could be obtained at 

 the study site or near vicinity, a stage-discharge relationship and flood 

 frequency analysis were included in the data package. For the rivers that 

 had no past flow records, the hydrology was synthesized using a regional 

 flow analysis (Lamke 1979). 



Hydrau I i cs . Hydraulic parameters for each river channel and f I oodp I a i n 

 were measured in the field. At each study site cross sections were surveyed 

 upstream from, within, and downstream from the area of gravel removal (in 

 conjunction with the aquatic ecology program) to measure the following 

 hydraulic parameters: width, depth, and area. All cross section locations 

 were documented and elevations referenced to temporary benchmarks. The 

 longitudinal slope of the water surface and, where possible, the bed were 

 surveyed. All surveys used standard surveying techniques. The discharge at 

 the time of the survey was measured using standard techniques (Buchanan and 

 Somers 1969). 



Materials and Sediment . Representative samples of the river's flood- 

 plain surface material were obtained upstream and downstream from the gravel 

 removal area using the photographic-grid method (Kellerhals 1971). These 

 were considered to be representative of the channel bed material. The size 



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