Figure 4. Instrumented platform (photo by T. E. White) 



experiment. The calibrations covered a wide range of flow conditions and used 

 sediment obtained from the Colorado River project site. These calibrations 

 provided gain, offset, and trend information to convert the sensor output to 

 sediment concentrations. For a discussion of the OBS, see Downing, 

 Sternberg, and Lister (1981). The ECM's were 2.54-cm-diameter 

 Marsh-McBimey electromagnetic current meters that measured two 

 components of horizontal velocity. Each ECM was calibrated prior to each 

 experiment, and the sled compass was used to rectify the ECM output into 

 long-shore and cross-shore components of velocity. The SAU on the platform 

 was attached to a shore cable enabling data transmission to an instrument van 

 located on the beach. Initially, data were logged and saved onto an onsite Vax 

 station. In later experiments, a PC-based system was used for data collection. 



Following the May 1990 experiment, it was determined that one 

 instnmiented platform did not provide the coverage desired for the project site. 



Chapter 3 MCCP Monitoring Plan and Implementation 



15 



