and bed, extending from just above the water's edge past the deepest part of the channel. Paving of the bank above the water's edge completes the revetment. Normally, the upper bank paving is composed of riprap stone or of an uncompacted mixture of sand and asphalt. Improvements in casting and placement techniques have kept pace with those in plant design. The result of this constant effort to place better revetment faster and cheaper has been an increase in placement rate to about 800 to 1,000 linear feet of bank per working day, an excellent safety record, and very low cost. The present total cost per square foot of revetment in place is less than 39 cents. Prevention of diversion of Old River. One of the outstanding and most dramatic features of the Mississippi River flood-control project is concerned with Old River control, a feature designed to prevent the threatened diversion of the Mississippi River to a shorter path to the Gulf of Mexico through the Old and Atchafalaya Rivers. The tendency of the Mississippi River to seek a new course to the Gulf of Mexico has been under observation by the Mississippi River Commission for many years and it is now evident that the diversion will occur within a relatively few years unless it is arrested. The effect of the diversion upon the area below the diversion, particularly the city of New Orleans, would be disastrous. Congress has authorized this important work and has appropriated $2,250,000 to initiate construction on the first of the structures necessary. The entire construction program, estimated to require eight to ten years for construction, calls for two control structures (a low-sill structure primarily for the passage of inbank flow, and an overbank structure for the passage of floodflows) on the west bank of the Mississippi River about 10 miles upstream from the confluence of the Old and Mississippi Rivers, raising and strengthening Mississippi River levees in the problem area to complete the closure of the Old River gap, and a navigation lock with navigation channels connecting the Mississippi and Old Rivers. This work is estimated to cost $80,800,000. 6. NIAGARA REMEDIAL WORKS The 1950 Niagara Water Treaty with Canada permits additional diversions of water for greatly increased power developments in the United States and Canada at the falls, and also expresses the primary obligation of the two Governments to preserve and enhance the scenic beauty of Niagara Falls and River. Pursuant to this obligation, a project was developed and approved by the two Governments for remedial works necessary to produce an unbroken crestline at the falls. The works consist of a control structure extending about 1,550 feet from the Canadian shore to a point about 1 mile above the Horseshoe Falls, and for excavations and fills on both flanks of the Horseshoe Falls, at an estimated total cost of $13,800,000 to b divided equally between the two Governments. With appropria tions made in fiscal years 1954 and 1955, totaling $3,500,000, th Corps of Engineers, as the designated construction agency for th Government of the United States, has completed its portion of th work consisting of excavation and fill on the United States side o the Horseshoe Falls and has initiated landscaping of the fill and th bank area adjacent to the completed excavation. The Ontari Hydroelectric Power Commission is performing the work in Canada consisting of the control structure and the excavation and fill required on the Canadian flank of the Horseshoe Falls. 7. GENERAL OPERATIONS Work done by contract. The Corps of Engineers for many years has consistently adhered to its policy of having construction work done by contractors in all cases except when the best interests of the United States require hired labor operations. This past year was no exception to the policy. In fact, 94 percent of all construction work was performed by contract and only 6 percent by Government plant and hired labor. In recent years the amount of construction by hired labor has remained at this low percentage. A larger percentage of the maintenance work has been performed by hired labor. The hired labor work on construction projects has been limited to such types of operation as dredging in exposed harbor entrances by Government-owned hopper dredge, the construction of erosion control and levee revetment works, and grouting operations. The nature of such work does not readily lend itself for advertising and performance by contract. Accident prevention. The attention which the Corps of Engineers has paid over the years to the prevention of accidents at all its construction and maintenance operations, whether by hired labor or contract, has paid sizable dividends in the improved welfare of construction workers, decreased loss of time on works, decreased costs and increased efficiency. Chart III shows the continued improvement in the disabling injury frequency rate on civil works projects for Government and contractors' employees. Fire prevention. Corps of Engineers' property and equipment lost by fires during the year amounted to $41,000, an increase of $34,000 over the fiscal year 1954. This increase resulted almost entirely from three fires ($32,500), which were beyond the control of the Corps of Engineers. Considering the value of all plant and equipment owned by the Corps of Engineers, the fire loss is exceptionally low. MILLIONS OF MANHOURS 50 DISABLING INJURY FREQUENCY RATE NOTE: The rate for the construction industry for the years 1954 and 1955 are not available. Chart III. CHAPTER III BENEFITS OF THE PROGRAM 1. Navigation. The historical policy of the United States has been and is to develop and maintain its waterways to promote its commerce and industry. The Federal program for improving the Nation's rivers and harbors, now in its 132d year, has produced one of the best systems of harbors, channels and inland waterways in the world. These navigation improvements carry a huge tonnage of valuable foreign and interstate commerce. The availability and use of water transportation have lowered prices by keeping the overall transportation bill of the Nation low, and has thus benefited all of the people, whether they live, work or operate businesses on navigable waters or some distance therefrom. As such, water transportation serves a most useful purpose in the overall economy of the Nation. This work was assigned by Congress to the Corps of Engineers and represents the oldest phase of the activity of the Corps of Engineers in water resource development. The navigation element of the civil works program consists of three major parts: Coastal harbors and channels, Great Lakes Harbors and channels, and the inland and intracoastal waterways. The following analyses of that program, based on 1953 costs and waterborne commerce, were presented to the Senate Public Works Committee in April 1955 and are considered to be generally representative of the present situation. Coastal harbors and channels. Improvement of these harbors and channels by the Federal Government has been a progressive development keeping pace with the growth of maritime commerce and the requirements of development of shipping. Natural facilities have been improved over the years from the relatively shallow depths necessary to serve sailing craft, to the greater depths required with the advent of steam shipping, and finally to handle the ocean carriers of today. As a result depths of 35 feet generally prevail at major harbors on the Atlantic and Gulf coasts, ranging up to 45 feet in New York Harbor, and depths of from 30 to 40 feet are generally available on the west coast. Harbors and channels of lesser depth have also been provided for commercial and sport fishing, general recreational boating, and for use as harbors of refuge. Commerce handled by coastal harbors and channels in the last quarter of a century has shown a steady increase from 307 million tons in 1929 to 480 million tons in 1954. A recent analysis of major coastal ports, given in table 16, indicates the small cost of the Federal improvements per ton of traffic. While these figures will vary somewhat from year to year it is believed that costs given fairly reflect current conditions. Table 16. Traffic and Annual Costs—Major Coastal Ports 1 1 From data presented to Senate Public works Committe in April 1955, based on 1953 costs and traffic. * Includes only portion of traffic at ports of New Orleans and Baton Rouge. 'Current estimate of annual maintenance. 4 Data for Calcasieu River and Pass. $ Data for Columbia and Lower Willamette Rivers below Portland. Great Lakes. The Great Lakes system serving the Middle West is the world's largest and busiest inland waterway. Eight States border on the Lakes, and nine others are directly tributary thereto. The Lakes have a total water surface area of about 95,000 square miles, two-thirds of which are in the United States. These vast water areas, |