Size of bathymetry

Does anybody know if there are limitations on size of bathymetry? I have 177 segments and 34 tributaries. I always get an array bounds error at bathymetry segment length (which is 500 meters) and illegal value or incorrect card error where tributary segments go over 100. I also got the array bounds error when I had 89 segments about 1000 meters long and for 45 segments about 2000 meters long.