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Junction of North and South Forks, Sher-
Junction of East and West Forks, Kauf
man County, Tex.
Junction of North and South Branches,
Junction of Coast and Middle Forks, near
Lae Vieux Desert, Vilas County, Wis.
Junction of Lewes and Pelly Rivers, Yukon
The length of a river is that of the channel to which the name generally is applied. The Snake River is in a definite canyon from Kinney Creek to the mouth of the Grande Ronde River, approximately 100 miles, although the designation Hell's Canyon might be applied to the 30 miles from Kinney Creek to Temperance Creek through which the river drops at the rate of about 1212 feet per mile. The width of the river through this part of the canyon varies from 100 to 500 feet,
and the width of the canyon varies from 5 to 10 miles.
The greatest width and greatest depth of Hell's Canyon is probably at He Devil, the elevation of which is 9.387 feet. The elevation of the Snake, northwest of He Devil, is 1,350 feet, making a difference in elevation, in 52 miles horizontally, of 8.037 feet.
The source of the St. Lawrence River is in the State of Minnesota. The St. Lawrence is viewed as a part of the Great Lakes Waterway and its source is considered the head of the St. Louis River which feeds into Lake Superior. The St. Louis River rises in Minnesota.
Area (sq. miles) of great river basins--Amazon (2,772,000); Congo (1,425,000); Nile (1,293,000); Mississippi (1,290,000); La Plata (1,198,000); Yangtze (689,000); Volga (592,000); St. Lawrence (565,200); Danube (320,300); Colorado (250,000); Rio Grande (232,300).
American span 800 ft.; Canadian, 750 ft.
The Henry Hudson Arch, Bridge, New York City, has the longest plate girder, fixed steel arch in the world. The main central span is flanked by 300-ft. continuous steel girder viaducts of 60-ft. spans.
The total length of steel is 1,555 feet and the total length of entire structure is 2,000 feet. Clearance, 142.5 feet, above high water; cost of lower level, $1,255,690; cost of upper level, $800,000. The upper level was opened in 1938.
The $18,000,000 Bronx-Whitestone Bridge is a link in the Belt Parkway program of the City of New York. It connects the Belt Parkway from the northerly end of the Cross Island Parkway on the Easterly boundary of Queens, across the East River into the Bronx where it connects with Eastern Boulevard and with the projected southern extension of the Hutchinson River Parkway leading to Westchester, upstate, and Connecticut.
The bridge is 4,000 feet long from anchorage to anchorage, with a main span of 2,300 feet, entire length including approaches, 7,140 feet; height of span above high water, 150 feet at center and 135 feet at Channel line near Bronx Shore. The bridge deck is 74 feet wide divided into two 29-ft roadways (separated by a curb) and two sidewalks. The towers are 377 feet high. The $35,000,000 Golden Gate Bridge (1933-1937) crosses the portal of the harbor of San Francisco. Its towers are 746 feet high; the deck is 200 feet above high-water at the center of the span. Eleven lives were lost during construction--ten of them on Feb. 17, 1937, when dislodged wood and steel tore open the safety net underneath the span and carried the men down into the water.
In the construction of the $77,000,000 cross-bay bridge which joins San Francisco and Oakland with a center rest on Yerba Buena Island, 24 persons were killed and over 1,100 were injured.
The $60,000,000 Triborough Bridge at N. Y. City is a toll structure and consists of a suspension bridge of 1,380 ft. channel span and 705 ft. side spans over the East River at Hell Gate; a vertical lift bridge over the Harlem River with lift span of 310 ft.; fixed truss spans over the Bronx Kills with channel span of 350 ft.; plate girder viaduct structure in Queens, on Ward's and Randall's Island, over Little Hell Gate and in Manhattan, and with concrete viaduct construction at points in Queens, Manhattan and the Bronx and at the junction of the Manhattan branch with the Queens to Bronx branch on Randall's Island.
The Thousand Islands International Bridge, formally opened on Aug. 18, 1938, extends from Collins Landing (near Alexandria Bay) in New York State to Ivy Lea (near Gananoque) in islands to reduce the span lengths required. Ontario. This crossing, 81⁄2 miles long, utilizes the
The crossing over the American channel, from the mainland to Wells Island, consists of a suspension bridge 800 ft. main span, with an underclearance of 150 ft. above the river.
The Canadian crossing includes: a continuous truss of two 300-ft. spans (from Hill Island to Constance Island), a steel arch of 348-ft. span (from Constance Island to Georgina Island), and a suspension bridge of 750-ft. span and 120 ft. underclearance from Georgina Island to the Ontario mainland. The boundary at the International Rift, between Wells Island and Hill Island, is bridged by a 90-ft. rigid frame arched span of reinforced concrete with masonry facing.
Near Seattle, Wash., a "ribbon" of 100,000 tons of floating concrete, stretching out across Lake Washington, drew crowds on July 2, 1940, for its dedication as the first pontoon bridge of its kind in engineering history. Built by the state with Federal financing assistance, it is the longest pontoon bridge ever built and the first of reinforced concrete. With connecting highway links, the structure provides a cutoff of 15 miles in crossstate travel.
The bridge is composed of 25 pontoons, each filled with watertight compartments. The pontoons are bolted together, and each has two or more 65-ton anchors. The four-lane bridge is more than a mile in length.
The span, built in a year and a half, was financed by a P. W. A. grant of $3,794,000 and a bond issue of $5,500,000, to be retired by toll charges.
The Calvin Coolidge Memorial Bridge, which crosses the Connecticut River near Northampton, Mass., was opened to traffic on Oct. 12, 1939.
The Connecticut River Bridge, between Middletown and Portland, the largest bridge in New England, formally opened on Aug. 6, 1938, is of steel and concrete and cost $3,500,000. Including the approaches, it is 3,420 feet in length.
A new bridge across the Mississippi River at La Crosse, Wis., was opened in Sept., 1939. It is of steel and concrete and is 2,206 feet long. One of Europe's longest bridges, 10,432 feet, completed in September, 1937, extends across the sound, between the Danish islands of Zealand and Falster. It cost about $8,844,000.
Chief Federal Canals in the United States
Source (as of June, 1941): Chief of Engineers, U. S. Army. Canals in italics are ship canals
Atlantic Intracoastal System
Cape Cod Canal, Mass..
Buzzards Bay-Cape Cod Bay....98%.
Inland Waterway, Md. & Del...Chesapeake Bay-Delaware River
Inland Waterway, Va., & N. C.
(includes Chesapeake & Dela-
Norfolk, Va.-Beaufort, N. C.. 1935
22 2 2 2877
Upper Mississippi River (26 Mouth of Missouri River to Minlocks and dams)..
Illinois Waterway (8 locks and]
Ohio River (46 locks and dams)
(a) Width through Dismal Swamp Section, 50 feet. (b) Route via Harvey Canal. Alternate route through Plaquemine Lock, 639.5 miles. (c) Upstream Channel. (d) Downstream Channel. (e) Lock width for Locks 2 to 26, incl.; Lock No. 1 has chamber width of 56 feet. (1) Channel open to navigation. Construction under way to obtain full project dimensions. (g) Ninefoot depth available. Locks and dams completed but not all auxiliary works.
(h) Project depth available. Work remaining acquisition of flowage easements.
(1) Project depths available except between Vancouver and Bonneville. This reach now under construction. (1) Columbia River, Mouth to Bonneville, 300-500 ft. wide. Bonneville to Dalles, Ore., ample width in open lake. Completion status of Okeechobee, Houston Ship, Keweenaw, Warrior River, and Columbia River is as of Jan., 1941; the others are as of June, 1940.
Cargo Traffic on Chief American Canals
Source: Board of Engineers for Rivers and Harbors, U. S. War Department
Dollars 1,021,528,978 1,135,390,357 1,233,967,221
982,987,481 75,779,280 1,079,854,740
46,808,613 51,334,641 72.897,752 760,968,185 45,726,085 48,293,308 688,004,883 29,184,768 270,865,557 4,489,172 69,528,600 799,786,656 44,516,827 356,021,355 5,014,206 87,633,699 925,644,409 57,138,579 446,071,717 5,010,464 40,042,739 581,521,592 23,060,630 272,066,115 38.048.406 343,062,814 4,689,037 54,147,695 407,484,967 4,768,160
Value figures for the Detroit River and Sault Ste. Marie have not been compiled since 1938. The Duluth-Superior valuations for the commodities, the U. S. Engineers Office states, were largely derived from daily or weekly prices current and from quotations by principal shippers, owners, and carriers, and represent valuations at Lake Superior ports. The valuations of all Canadian and foreign commodities were obtained from the U. S. Customs Service.
Description of the Panama Canal
Lake. Madden Lake covers approximately 22 square miles at maximum level, 260 feet above sea level, providing reserve storage of 22 billion cubic feet of water for use in maintaining the level of Gatun Lake during dry seasons.
Source: Governor of the Canal Zone
There is no difference between the average mean level of the Pacific at Panama and the Atlantic at Colon. But at Colon there are small tides of 1 foot and at Panama large tides of 10 feet above and below the average level.
On the Atlantic slope the Canal follows the former valley of the Chagres River; on the Pacific, that of the Rio Grande. Dams were built across these valleys to form lakes on which the ships are floated, and connection between the two valleys, through the intervening divide, was made by excavating Culebra Cut (officially named Gaillard Cut).
The summit elevation, i. e., the surface of Gatun Lake and of Gaillard Cut, which is an artificial arm of the lake, is normally 85 feet above sea level, and the bottom of the Cut was excavated to 40 feet above sea level, giving normal depth of 45 feet. The channel through Gatun Lake is 2334 miles long, and the Cut is 8 miles long.
The locks serve to raise ships from the sea to the summit level, or to lower them to sea after they have crossed the Isthmus. On the Atlantic side the lift is made at Gatun Locks, which have 3 steps or chambers, called lower, middle, and upper. On the Pacific side, one step is made at Pedro Miguel Lock, at the Pacific end of Gaillard Cut, and two at Miraflores Locks, about a mile to the south: between them is Miraflores Lake, with its surface normally 54 feet above sea level. Sections at sea level extend between the Atlantic Ocean and Gatun Locks, 62% miles, and between the Pacific and Miraflores Locks. 8 miles.
The line of the Canal is northwest-southeast, and the Pacific end is 27 miles east of the Atlantic end. The Canal is 44.04 nautical miles or 50.72 statute miles in length, at least 300 feet wide at the bottom of excavated channels, 110 feet wide in the lock chambers, which have a usable length of 1,000 feet. Depth varies but is not less than 41 feet in sea level sections or with surface of Gatun Lake.
The Canal can handle any ship except the Normandie, the Queen Mary, and the Queen Elizabeth, which are too large for the lock chambers.
A concrete dam across the Chagres River at Alhajuela was completed in 1935, creating Madden
miles at normal level. It is impounded behind Gatun Lake covers approximately 165 square Gatun Dam, built of rock and earth across the Chagres River at Gatun, connecting the hills on either side with a low hill near the center of the valley.
The Canal Zone is a strip of land extending five miles on either side of the center line of the Canal but excluding the cities of Colon, at the Atlantic end, and Panama, at the Pacific, which remain within Panama. It has by the census of 1940 a population of 51,827. Work on special defense projects and for building a third set of locks has resulted in a considerable increase of civilians in the past year.
The Zone was granted to the United States by the treaty with Panama of February 26, 1904. The United States paid Panama $10,000,000 and $250,000 per year after the ninth year, and subsequently paid Colombia $25,000,000 under the treaty of 1922. The United States has acquired title to all of the land in the Canal Zone, reimbursing private owners, and no land is now available for private ownership.
American occupation of the Canal Zone began on May 4, 1904, and the Canal was opened to traffic on August 15, 1914. Traffic in the early years was hampered by slides and reduced by war conditions, and the Canal was declared officially opened on July 12, 1920. The end of the fiscal year 1921 was adopted as the date the Canal could be considered completed, and the cost as of June 30, 1921, with interest on the investment in earlier years compounded annually at 3%, was established by the Bureau of Efficiency at $525,812,661.
The Canal Zone is a Government reservation administered by the organization known as The Panama Canal. This is an independent organization in the Government service whose head is the Governor, directly under the President. As a matter of executive arrangement, the Secretary of War represents the President in the administration of Canal Affairs. The Zone is fortified and occupied by a garrison in addition to the civilian employees of the canal and railroad.
The Army maintains air ports at France Field on the Atlantic side and Albrook Field on Balboa Heights on the Pacific side.
Third Locks Project
The Third Locks Project, providing for the construction of an additional set of locks located approximately parallel to, but at some distance from, the existing locks at Gatun, Pedro Miguel and Miraflores. and for the construction of the necessary by-pass channels connecting the new locks with the present Canal channel, together with such appurtenant facilities as may be deemed necessary, at a total cost not to exceed $277,000,000, was authorized by Act of Congress, approved August 11, 1939.
This legislation authorizing the construction of additional facilities in the Canal Zone was enacted for the purpose of more adequately providing for the defense of the Panama Canal and for increasing its capacity for the future needs of interoceanic shipping.
The locks of this new project are to have available dimensions of 140 feet by 1,200 feet, with a 45-foot salt water draft over the sills. Actual work on the new project started July 1, 1940.
Cargo Traffic on Chief Foreign Canals
Source: Official Reports of the Several Waterways
Note: F. C. Flood Control; P. Power; Irr. Irrigation; W. S. Water Supply; Nav. Navigation.
1933, under the provisions of the National Industrial Recovery Act, The project was formally authorized by Congress in the River and Harbor the Columbia River about 42 miles east of Portland, Act approved August 30, 1935. It is located on way. The main features of the work are a dam, Oregon, and may be reached by railroad and higha powerhouse, a ship lock, and fishways. The total estimated cost of the project, with an installation of ten power units is $75,000,000. DAM, OREGON
GRAND COULEE DAM, OREGON The Grand Coulee Dam turned over its first, generator on March 22, 1941 (2 years ahead of schedule), and sent 10,000 of an ultimate capacity of 1,974,000 kilowatts, or 2,475,000 horsepower, into the network of transmission lines of the Bonneville Power Administration. This agency is charged with distribution of power from the Grand Coulee and Bonneville projects over the Pacific Northwest. Improvement of the Columbia River at Bonneville, Oregon, was undertaken on September 30, BONNEVILLE Improvement of the Columbia River at Bonneville, Oregon, was undertaken on September 30, 1933, under the provisions of the National InThe project was formally dustrial Recovery Act. authorized by Congress in the River and Harbor Act approved August 30, 1935. It is located on the Columbia River about 40 miles east of Portland, Oregon, and may be reached by railroad and The main features of the work are a highway. dam, a powerhouse, a ship lock, and fishways. The total estimated cost of the project, with an installation of ten power units is $75,000,000.
The dam, locks, existing power plant with its present installation of four units and appurtenant works at Bonneville have been constructed, and are being maintained and operated, under the
direction of the Secretary of War and the super-
BOULDER DAM (BOULDER Boulder Dam is the principal engineering feature of the Boulder Canyon Project, authorized December 21, 1928 for construction by the Bureau of Reclamation. It is the highest dam in the world, and is located in Black Canyon of the Colorado River where
that stream forms the ArizonaNevada boundary about 25 miles southeast of Las Vegas, Nevada. The dam was completed March 1, 1936, four years, 354 days after work was begun. The dam rises 726.4 feet above bedrock, and is
The reservoir formed by Boulder Dam is called Lake Mead, named for Dr. Elwood Mead, Commissioner of Reclamation, who died January 26. 1936, during the construction period. Lake