Preventive measures 28 General discussion 28 Lower valley improvements 29 Flood catchment 31 Pompton reservoir 31 Ramapo system 33 Wanaque system 34 Midvale reservoir 34 Ringwood reservoir 35 West Brook reservoir 35 Pequanac system 35 Newfoundland reservoir 36 Stickle Pond reservoir 36 Rockaway system 37 Powerville reservoir 37 Longwood Valley reservoir 37 Splitrock Pond 38 Upper Passaic Basin 38 Millington reservoir 38 Saddle River 39 Summary of flood-catchments projects 40 Preferable reservoir sites 40 General conclusions 44 Index 47 ILLUSTRATIONS. Page. PLATE I. _A_, Beattie's dam, Little Falls, N. J., in flood; _B_, Flood-water lines in residence district, Paterson, N. J. 16 II. _A_, Pompton Lakes dam and water front of Ludlum Steel and Iron Company; _B_, Dry bed of Pompton Lake 24 III. Flood district of Paterson, N. J. 24 IV. _A_, Washout at Spruce street, Paterson, N. J.; _B_, River street, Paterson, N. J., after flood 26 V. _A_, Effects of flood in mill district, Paterson, N. J.; _B_, The wreck of a hotel in Paterson, N. J. 26 VI. _A_, Devastation in Hebrew quarter, Paterson, N. J.; _B_, A common example of flood damage 28 VII. _A_, Inundated lands at Passaic, N. J.; _B_, Undamaged bridge across Passaic River after partial subsidence of flood 28 FIG. 1. Comparative flood run-off at Dundee dam, March, 1902, and October, 1903 18 2. Diagram of flood flow at Dundee dam, flood of 1903 20 LETTER OF TRANSMITTAL. DEPARTMENT OF THE INTERIOR, UNITED STATES GEOLOGICAL SURVEY, HYDROGRAPHIC BRANCH, _Washington, D. C., December 4, 1903._