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Statement Number 4020 4575 5020 5070 5227 5290 5470 5730 6070 6110 Exhibit 7 Page 6 of 8 Notes and Remarks 80 TRIALS NOT ENOUGH FOR CRITICAL DEPTH. This note indicates a data error or program error has been detected. If no data error is detected, job should be rerun, with ITRACE equal to one, in order to obtain reason for failure of parabolic opti- mization process. CRITICAL DEPTH ASSUMED BELOW ELLC OF - EGLC = EGC - - WSEL - Critical depth is being computed in a bridge section and the minimum energy below the low chord is less than the minimum energy above the top of the bridge. SPECIAL BRIDGE. The input has specified that the bridge routine to be used for this cross section is a special bridge routine. VARIABLE ELCHU OR ELCHD ON CARD SB NOT SPECIFIED. The eleva- tions of the channel upstream and downstream of the bridge are not specified on input fields and have therefore been assumed equal to the previous cross sections minimum elevation. DOWNSTREAM ELEV IS X, NOT Y. HYDRAULIC JUMP OCCURS DOWNSTREAM. The upstream momentum is so great that the water downstream of the bridge is supercritical and not subcritical. UPSTREAM ELEVATION IS X NOT Y, NEW BACKWATER REQUIRED. Since supercritical flow was assumed by input and since the bridge obstruction drowns out the supercritical flow upstream of the bridge, new backwater is required, from the bridge upstream. ERROR DS DEPTH WRONG SIDE CRITICAL. The calculated depth in the low-flow routine was determined on the wrong side of critical depth. If this error occurs, a programming error has been discovered. Run with ITRACE = 1 and determine the cause. See note 3710. LOW FLOW BY NORMAL BRIDGE. When the pier width is specified as zero for the special bridge routine and when low flow controls, the friction loss for the bottom and sides of the channel are computed using the normal bridge routine instead of the special bridge routine. EGLWC OF X LESS THAN XEG OF Y. The energy gradient elevation for the controlling low flow is less than the previous cross section's energy gradient indicating negative losses. The energy gradient elevation for the current cross section is therefore assumed equal to the previous energy gradient (no loss) and the run has been continued.