  ****UNKNOWN SOURCE--  DEPTH OVER CRIB 33 FT WAS APPLIED BEFORE 1975 TO THE LAKE SURVEY CHART BEFORE NOS TOOK OVER THE CHART.
  L1156/92-- 9/18/92; REVISED THE DEPTH OVER CRIB TO 38 FT. THEN L1156/92 WAS REAPPLIED IN 1993 AND REVISED THE DEPTH OVER CRI