The Third Locks Project

MISSING IMAGE

Material Information

Title:
The Third Locks Project
Alternate title:
Panama Canal, the Third Locks Project
Physical Description:
16 p. : col. maps ; 26 cm.
Language:
English
Creator:
Canal Zone
Canal Zone -- Third Locks Project
Publisher:
Panama Canal
Place of Publication:
Balboa Heights, Panama
Publication Date:

Subjects

Subjects / Keywords:
Canals, Interoceanic -- Design and construction   ( lcsh )
Canals -- Design and construction -- Panama -- Canal Zone   ( lcsh )
Locks (Hydraulic engineering) -- Design and construction -- Panama -- Canal Zone   ( lcsh )
Panama Canal (Panama)   ( lcsh )
Genre:
federal government publication   ( marcgt )
non-fiction   ( marcgt )

Notes

General Note:
Cover title.
General Note:
"June 1941."

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
oclc - 01955384
ocm01955384
Classification:
lcc - TC774 .C428 1941
ddc - 626
System ID:
AA00019286:00001

Table of Contents
    Front Cover
        Front Cover 1
        Front Cover 2
    Foreword
        Foreword 1
        Foreword 2
    The Panama Canal Third Locks Project
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 5a
        Page 6
        Page 6a
        Page 7
        Page 7a
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
    Statistics: Third Locks Project
        Page 14
        Page 15
        Page 16
        Page 17
    Back Cover
        Back Cover 1
        Back Cover 2
Full Text

THIRD


PROJECT





JUlE 1941


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FOREWORD


This pamphlet is for the purpose of presenting general

information for visitors to the Panama Canal and others who may

be interested in the principal features of the Third Locks Pro-

ject which is now under construction to increase the capacity of

the Canal. At this time construction has just begun and the

detailed designs are not yet fully complete. The information

contained in this pamphlet is based on the estimates and designs

as they exist today and so should be accepted as in some mea-

sure tentative and subject to revision as further studies, tests,

analyses and detailed designs are completed.










GLEN E. EDGERTON,
G o v e r n o r .



June I, 194i

Gift of e Panama Canal Mu .um














THE PANAMA CANAL

THIRD LOCKS PROJECT


Current international events and the beginning of con-
struction on the Third Locks Project to increase the capacity and
aid in the defense of the Panama Canal again focus world atten-
t ion on the Isthmus of Panama.

Panama has long been important in New World history
because of commerce crossing the Isthmus. Construction of the
Panama Canal attracted wide-spread public attention and com-
pletion of the project marked the beginning of a new phase in
interoceanic shipping. The commercial success and military
importance of the Canal are today common knowledge.

The uninterrupted use of the Canal and its military
value are of such importance that Army and Navy strategists have
extensively studied the defense of the Canal and considered the
desirability of enlarging the Panama Canal or constructing a
second canal in some other location across Central America. The
original builders were aware that the Canal's capacity would
eventually require enlargement, for the project was planned with
an optimum size which would be ample for a reasonable period but
which would not include excess capacity that would belong unused.

While history assured the eventual success of the Canal
project, there was nothing to indicate the rapid growth in ship
size whichwas to follow the opening of the Canal Probably few,
if any, of the most optimistic builders of the original Canal
would have dared predict that enlargement of the Canal would be
under way as early as the year 1941.

SOfficially anticipating the need for enlargement of the
Panama Canal, or construction of a new canal at some other loca-
tion, Congress in 1929* authorized the President to cause to be
made, under the direction of the Secretary of War and the super-
vision of the Chief of Engineers, and with the aid of such
civilian engineers as the President deemed advisable, a full and
complete investigation and survey for the purpose of ascertain-
ing the practicability and approximate cost of constructing and
maintaining (I) such additional locks and other facilities in the
Panama Canal as may be necessary to provide for the future needs
of interoceanic shipping, and (2) any other route for a ship
canal between the Atlantic and Pacific Oceans. The Act specifi-
cally provided, in part, for a survey of a canal route across the
Republic of Nicaragua.


*Pub I Ic Resol ut ion No. 99, 70th Congress, approved March 2,
1929.









In accordance with the legislation cited, two reports were
prepared, one by the Governor of The Panama Canal which considered the
construction of an additional set of locks and ultimate conversion of the
Canal to sea level; and the other, a report by Lt. Colonel Dan I. Sultan,
C.E., concerning the Nicaraguan route. Both reports proposed construction of
locks 1,200 feet long, 125 feet wide, and 42.5 feet deep. At that time,
it was estimated that a third set of locks at Panama would cost $140,000,000
and that to lower the Canal to sea level would cost $1,000,000,000. The
cost of the proposed Nicaraguan Canal was estimated at $697,000,000 plus
$25,000,000 for rights, franchises, lands, etc. The maintenance cost of the
Nicaraguan Canal was estimated at $10,800,000 a year, which was an amount
greatly in excess of the added cost of operating a third set of locks at
Panama. The interoceanic Canal Board reviewed the reports, visited the
Canal sites and concluded that no immediate steps were then needed to pro-
vide increased facilities for passing water-borne traffic from ocean to
ocean, that the construction of a third set of locks and conversion of the
Panama Canal into a sea-level canal was the most practical solution to the
problem, but that at some later date consideration should be given to the
Nicaraguan Canal.

Nicaraguan Canal

The route considered most practical for an interoceanic ship canal
across the Republic of Nicaragua was from Greytown, on the Atlantic Coast, to
Brito, on the Pacific Coast, by way of Deseado and San Juan Rivers and Lake
Nicaragua. The Nicaraguan Canal would be 173 miles long, as compared with 51
miles for the Panama Canal. Like the Panama Canal, locks near each coast
would be necessary to lift ships to the elevation of the lake surface, 105 to
110 feet, and for 70 miles the Canal would be through Lake Nicaragua. The
lock size and canal cross section were the same as that considered for the
Third Locks at Panama and it was estimated that the Nicaraguan Canal would
have a capacity of about 180,000,000 tons a year. To construct a canal
across Nicaragua, a complete organization similar to that at Panama,
including Civil government and community developments, would be necessary,
and to defend the location, a second Central American Defense Unit would be
necessary.

Enlargement of the Panama Canal

The Report of the Governor of The Panama Canal, dated August 4,
1931, submitted in connection with the studies authorized by the Act of
1929, considered a project for a third set of locks with a project for con-
verting the Panama Canal into a sea-level canal. With the completion of
Madden Dam in 1934 and the resultant increase in water supply, the Governor
was of the opinion that a third set of locks would not be needed until about
1970, and that such locks, if constructed over a period of ten or twelve
years prior to that time, would be ample to care for increased shipping
needs for a long future period. The third locks considered at that time
were to be parallel and contiguous to the existing locks. The increase in
capacity would be between 40,000,000 and 45,000,000 tons per year. It was









considered that to lower the Panama Canal to sea level would require from
35 to 40 years for most economical construction, and that as a step in lower-
ing the Canal to sea level, it would be necessary to construct a third set of
locks. In view of the time required for conversion, it was estimated that
the project for lowering the Canal to sea level should start shortly after
the third locks were completed. Construction schedules were prepared to
provide for the lowering of the Canal channel by dredging and the alternate
lowering of various locks so that traffic through the Canal would be un-
interrupted. The Governor recommended that no project for a sea-level camal
at Panama be then adopted and that tentative plans for the future contem-
plate increasing the capacity of the lock canal by a third set of locks. It
should be noted that the estimated cost of $140,oo000,000 for the third set of
locks did not provide for locating the locks at some distance from the old
structures, as is now being done, nor did it provide for the larger dimen-
sions now planned or for the incorporation of safety features, now considered
essential for the third locks.

Third Locks Authorization

In 1936 the Governor of The Panama Canal was authorized and
directed by Congress* to investigate the means of increasing the capacity of
the Panama Canal for the future needs of interoceanic shipping, and to pre-
pare designs and approximate estimates of cost of such additional locks and
other structures and facilities as are needed for the purpose. In accord-
ance with this legislation, the Governor submitted a report, dated February
24, 1939**, wherein it was considered that construction of an additional
system of locks should be started within 10 or 12 years on the basis of
commercial requirements alone. Consideration of defense caused the Governor
to recommend that the new locks be constructed at some distance from the old
locks, requiring approach channels to connect with the existing waterway.
Because of the incorporation of defense features and the necessity of ex-
cavating approach channels, the Governor estimated the cost of the project at
$ 277,000,000.

On August II, 1939***, Congress authorized the construction of a
third set of locks in Panama, substantially in accordance with the plans
contained in the Governor's report, for the purpose of more adequately pro-
viding for the defense of the Panama Canal and for increasing its capacity
for the future needs of interoceanic shipping. As provided in the Gov-
ernor's report, the new locks at the Pacific end of the Canal are to be from
1,500 to 3,000 feet westerly of the existing Pacific side locks, and the New
Gatun Locks are to be about 3,000 feet easterly of the old Gatun Locks. The
locations are shown on maps on the following pages. The War Department Civil


*Public Resolution No. 85, 74th Congress, approved May 1, 1936.
**House Document No. 210, 76th Congress, first session.
***Pub l ic No. 391, 76th Congress









Appropriation Act of 1941 provided funds in the amount of $15,000,000 to
begin work on the project, and provided that the Governor of The Panama
Canal could, when authorized by the Secretary of War, enter into contracts
prior to July I, 1941 for, or on account of, the Third Locks construction to
an amount not in excess of $99,000,000.

Initial Work

Following authorization of the Third Locks Project and prior to
the appropriation of funds for construction, existing Canal forces had begun
plans for the design and construction so that the least possible delay would
ensue when funds were made available. Thus, on July I, 1940, the dipper
dredge, CASCADAS, started the subaqueous excavation for the Third Locks
Project. At the same time, offers of employment were extended to previously
selected, specially qualified men throughout the United States to fill key
positions in the Third Locks design and construction organizations. Per-
sonnel was rapidly assembled to prepare designs and to supervise the early
construction stages. As with most major construction projects, personnel
housing and care was the first major item to be considered.

The town at Diablo Heights, about 2 miles north of Balboa Heights,
had been started to provide housing for employees working on protective
features of the existing locks, and when Third Locks funds became available,
the town was expanded and designated as headquarters for the construction of
the new locks. To care for increased American personnel (usually referred to
as Gold employees) on the Atlantic side, a new townsite, Margarita, was
laid out about 2L miles southeast of Cristobal. Construction of living
quarters and public buildings in this town has been rapidly advanced and it
was first occupied in January of 1941. Native tropical laborers (usually
referred to as Silver employees) on the Atlantic side will be housed in a
newly developed camp near the existing town of Gatun. To care for employees
immediately connected with the construction of the Pacific side locks, a
townsite was laid out at Cocoli on the western side of the Canal, approxi-
mately opposite Diablo Heights and construction of this town is now in
progress. Provisions are made in this location to care for both Gold and
Silver personnel. Diablo Heights, Cocoli, and Margarita are complete towns
in themselves, each having a commissary, post office, school, clubhouse, fire
station, dispensary, et cetera. Contractors will, in general, provide
buildings for use of their employees who will reside in these new Third
Locks towns. It is estimated that at the maximum, about 2,300 people will
reside in Diablo Heights, 2,500 in Cocoli, and 1,500 in Margarita, including
families of employees. The Third Locks townsites are shown on Plates I, II
and III on the following pages.

The Special Engineering Division of the Department of Operation and
Maintenance was organized to handle all matters relating directly to the
Third Locks Project, including both the design and actual construction, but
existing organizations and facilities of The Panama Canal are being utilized
to the fullest possible degree in prosecution of the Third Locks work.
Regular Canal organizations have developed the new townsites and constructed





























































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the quarters for new employees. Existing personnel, payroll, supply, legal,
and other sections of the regular Panama Canal organization handle Third
Locks matters with regular and added personnel, thereby avoiding duplication
of these functions in the Special Engineering Division.

Design of the new locks was facilitated, as necessary basic data
for use in connection with the Third Locks Project have been collected for a
number of years as a regular part of the maintenance work of various units of
The Panama Canal, and surveys and studies made in connection with various
reports called for by Congress were planned, and records preserved, with a
view to their use when construction of a new set of locks was authorized.
Accordingly, when work began on detailed designs early in the fiscal year
1941, most of the basic data were at hand and many of the general features to
be incorporated in the Third Locks were already established. To determine
the exact Locks locations, subsurface exploration previously begun was con-
tinued by means of core boring and test pits, and materials were tested for
bearing power, compaction, permeability, et cetera. At the time of this
writing, about 100,000 lineal feet of core drilling has been completed in
connection with the Third Locks Project. Hydraulic model studies were
undertaken to determine the best design for the hydraulic features of the new
locks and a testing laboratory was established to determine the best ma-
terials for use in the locks and to test, and insure conformance with
required standards, materials used in the new construction.

Features of the New Locks

Although only a few existing ships are too large to be accom-
modated by the old locks, studies of shipping and naval requirements indicated
that the new locks should be 1,200 feet long, 140 feet wide, and 45 feet deep
to provide for the largest existing vessels and others still larger, likely
to be constructed in the future. Ships of 100,000 tons displacement, or
probably larger, could use the new locks. Plate IV on the following page
shows the growth in ship sizes in recent years. Studies of present locks'
operating methods will permit modifications in the design for the new locks
which will add to the safety and ease of their operation. In general
aspects, the new locks will be similar to the old locks, except that long
symmetrical, slightly flaring guide walls will be used instead of a single
long straight wall along one side of the lock approach, and a short sharp
flaring wall on the other.

The magnitude of the Third Locks Project is indicated by the
estimated quantities of major items in connection with Third Locks construc-
tion, as tabulated on the last pages herein.

Excavation Plan

Material to be excavated from the new locks' sites and approach
channels varies from the hardest basalt rock to soft mud. The Atlantic
approach to the New Gatun Locks, about 7,800 feet long, and the Pacific
approach to the New Miraflores Locks, about 8,000 feet long, are through





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CITY OF PARIS
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swamps. Excavation in these low areas has been started and will be done by
floating dredges of The Panama Canal Dredging Division. Soft material will
be removed by suction dredges and deposited to build up near-by low areas and
the harder material, much of which will require blasting, will be loaded on
barges by dipper dredges, and dumped in deep water at sea. A small amount of
dredging will also be required in Miraflores Lake, adjacent to the new lock
approach channels. To fully utilize the increased depth of the new locks,
the Atlantic entrance to the Canal will be deepened 4 feet by dredging. The
last phase of the new locks project will be removal, by dredging, of the
land plugs, or dams, which will be left at the ends of the dry excavation
jobs to prevent the in-flow of water during construction.

Excavation of the actual lock sites, the north approach channel to
the New Pedro Miguel Lock, and the south approach channel to the New Gatun
Locks, is possible by ordinary dry land methods and excavation in these
areas will be by contract. The magnitude of the project and the long time
involved in both planning and executing the work make it desirable to
excavate and place the concrete in the lock structures under separate
contracts. Concrete construction will not begin until the latter part of the
year -1942. While it was possible to begin the "wet" excavation by dredge as
soon as funds were available for Third Locks work, excavation by contract
was necessarily delayed until the locks' design was sufficiently advanced to
permit the excavation limits to be fixed and contract plans to be prepared.

Contract Work

NEW GATUN LOCKS. By October, 1940, geological studies and the
design of the new locks had advanced sufficiently to permit advertising for
the New Gatun Locks Structure, South Approach Channel and Appurtenant Works.
Prior to the opening of bids on December 4, 1940, the locks' site had been
cleared of jungle growth by Government forces and the many utility changes
and highway relocations required by construction of the new locks had been
started by the various Canal organizations which normally prosecute such
work, At the opening of bids in Washington, D. C., Martin Wunderlich Company
and Okes Construction Company were the low bidders on the Gatun excavation
contract, with a bid of $8,517,100. Upon award of the contract, construction
equipment was moved to the Canal Zone and on February 19, 1941, the first
power shovel began excavation of the new locks' site.

The contractor has elected to excavate the northerly section of the
locks' site by hydraulic dredge, as the material will be largely soft muck.
The dredge will be constructed on the site. The central and southerly parts
of the locks' site and the south approach channel, where clay, sandstone and
agglomerate will be encountered, will be excavated by tractor-drawn carrying
scrapers and by power shovels, draglines, and various types of large hauling
equipment. Excavated material will be used to fill in Stilson's Pond,
southeast of the town of Gatun, and to fill and level other low areas in the
vicinity of Gatun and Fort Davis. In addition to excavating for the locks
proper, the contractor at Gatun will grade for the relocation of the Panama
Rsilroad and excavate a new drainage canal east of the locks' sitesto control









drainage from areas to be filled with waste material. Since construction of
the new locks will make an island of the section of land between the old and
the new locks and on which the town of Gatun is situated, the main line of
the Panama Railroad which formerly ran through Gatun will be moved so as to
remain on the east side of the new locks. The relocated section of the
railroad will be 3.9 miles long, and will shorten the main line distance
from Colon to Panama City by 2-2/3 miles. About 12,000,000 cubic yards of
excavation will be required under the New Gatun Locks excavation contract.

At the time of writing, June I, 1941, excavations for the New Gatun
Locks totals 1,700,000 cubic yards, excavation for the railroad relocation
60,000 cubic yards, and excavation for the drainage canal 86,000 cubic yards,
and the excavation is 15% complete.

Excavation of the first section of the locks' site is to be com-
pleted in 510 calendar days so that placing of concrete by another contractor
may begin. A second section must be completed in 810 calendar days and a
third section, which completes the contract, must be finished in 960 days.
The locks excavation is about 9,040 feet long and the south approach channel
about 460 feet long. the maximum depth of cut will be about 210 feet, and the
maximum width about 1,060 feet. These maximums do not occur in the same
location due to the nature of the material to be excavated.

NEW MIRAFLORES AND PEDRO MIGUEL LOCKS. Bids for the excavation of
the New Miraflores and Pedro Miguel Locks sites, the Pedro Miguel North
Approach Channel and Appurtenant Works, were opened in Washington, 0. C., on
April 17, 1941. The low bid of $22,436,086 was submitted by the Panama
Constructors and award of the contract was made April 24. Work required by
this contract will begin by June 10. This contract will require the excava-
tion of about 28,700,000 cubic yards of material, the crushing and stockpiling
of 2,150,000 cubic yards of rock from the excavation, to be later used for
concrete aggregate, the grading of about 3 miles of railroad location and 4.6
miles of highway location, and construction of a 250-foot reinforced-concrete
highway and railway bridge. Excavation waste is to be used to fill low areas
including a small arm of Miraflores Lake, in the vicinity of the locks, and
provide leveled areas for use in future operations. The work is divided into
three sections: Section I, Hiraflores Locks sites, 7, 100 feet long, to be
completed by the contractor in 400 calendar days; Section II, the Pedro
Miguel Lock's site, 5,746 feet long, to be completed in 660 calendar days;
and Section III, the Pedro Miguel North Approach Channel, 7,850 feet long, to
be completed in 1,200 calendar days. The material to be excavated consists of
clay, mud, agglomerate, culebra, cucaracha, and hard basalt. Maximum depth
and width of excavation for the locks is 213 feet and 1,050 feet respectively.
Preparation of the railroad grade will require a maximum cut of 104 feet and a
maximum fill of 65 feet..

WET EXCAVATION. Excavation by dredge has continued since the begin-
ning of the fiscal year 1941. To date 1,840,000 cubic yards of material have
been removed by suction dredge from the Atlantic entrance by-pass channel and
1,560,000 cubic yards of earth and rock have been removed by dipper dredge








from the Pacific entrance by-pass channel. Drilling and blasting of rock and
hard material are now in progress by both floating and land equipment in the
by-pass channels. To expedite the dredging, several new tugs and barges have
been or will be purchased and a contract has been let for a new 28-inch
suction dredge.

APPURTENANT WORK. In constructing the Third set of Locks, there are
numerous appurtenant works to be constructed and many existing utilities and
facilities to be relocated or replaced. One of the major items now being
constructed is the Miraflores Swing Bridge, which will provide both rail and
highway access to the west side of the Canal and to the new Pacific Locks'
sites. The movable bridge will have two main spans, each 184 feet long, which
will cross the old Miraflores Locks approach channels aRfd rest on a common
center pier on the locks' center wall. The balancing spans which swing opposite
the main span will each be 92 feet long. The east approach to the bridge
across the Rio Grande will be a steel and concrete viaduct resting on 26
bents. The bridge and approach structure have a total length of about 2,250
feet. Construction of the substructure for the bridge is under way by Panama
Canal forces, and a contract for fabrication and erection of the superstructure
was signed with the Pittsburgh-Des Moines Steel Company early in April, 1941.
The contract price is $1,078,840 and the work involves the fabrication and
erection of about 5,500,000 pounds of structural steel in the East Approach
Viaduct, 2,450,000 pounds in the movable bridge and390,OOO pounds of machinery.
The contract requires completion of the East Approach Viaduct by January 8,
1942, and completion of the entire contract by March 29, 1942.

Another major appurtenant work now well-advanced is the construction
of 30 Quartermaster, Motor Pool, stable area and truck shed buildings to
replace structures which must be demolished to clear the New Gatun Locks site.
Other work includes the relocation of streets and highways, power and communi-
cation lines, water lines and reservoirs, and sewer and drainage lines and
structures. Ultimately a movable bridge will be constructed across the new
Miraflores Locks to provide continued rail and highway access to the west side
of the Canal, and another movable bridge will be constructed across the New
Gatun Locks to provide continued access to the town of Gatun which will be on
an island when the new locks are completed.

Design and Future Work

Having been successfully operated for over 25 years, the existing
locks structures and operating procedures are the basis for the new locks
design now in progress. The increased size of the new locks adds only slightly
to the design problem. The use of more modern machinery and control systems
will add to the ease and safety of new lock operation and extensive protective
devices will insure uninterrupted service. Completion of the design is being
expedited but standard laboratory tests and experiments are in progress to
insure adoption of the most suitable design.

Although the project is the largest single current engineering work
in the world, its planning and execution are not unduly involved, and principal
attendant problems not met in usual construction work are those usually ac-









companying tropical work, transportation, since supplies, equipment and
American personnel must all travel to the Canal by ship, and the supply of
tropical laborers. Increased Army, Navy and Canal construction has absorbed
all available Panamanian labor and made the recruiting of additional laborers
necessary in other Central and South American countries and in the Caribbean
Islands.

Contracts for furnishing cement and aggregate for the concrete in the
new locks will probably be advertised for bids late in the summer of 1941, and
bids for the concrete work itself are scheduled to be taken during 1942.
Construction of the locks structures will begin after completion of Part I of
each of the locks' excavation contracts and the construction contractors will
probably be allowed about 1,200 calendar days to complete the locks. The New
Gatun Locks dry excavation by contract is well begun, dredging is under way by
the Dredging Division in both the Atlantic and Pacific by-pass, or approach
channels, and major contract excavation operations on the Pacific side locks
will begin in June, 1941, but maximum activity on the project will probably
not occur until during the year 1944, when both concrete placing and excavation
will be in progress.









STATISTICS

Third Locks Project


LOCKS
Number of chambers to be constructed
Length of each lock chamber
Width of each lock chamber
Usable depth of each lock chamber
Total length, all new locks, including guide walls
Total excavation required (exclusive of approach
channels)
Concrete required for construction
Reinforcing steel to be used
Machinery and miscellaneous metal work

APPROACH CHANNELS TO CONNECT NEN LOCKS
WITH EXISTING CANAL
Total length
Maximum width
Minimum width
Minimum depth
Wet excavation required (by dredge)
Dry excavation required (by land methods)
Total excavation in approach channels

EXISTING ATLANTIC CANAL ENTRANCE, DEEPEN
FROH 42 TO 16 FEET
Excavation required (by dredging)

EMPLOYMENT (AS OF MAY I, 1941)
Special Engineering Division
Other Canal Divisions (employees temporarily on
Third Locks work, exclusive of new towns work)
Contractors (on Third Locks work)
Total
Estimated maximum employment


Total length, Third Locks and Approach Channels
Total excavation, Third Locks Project
Estimated total cost, Third Locks Project,
including appurtenant works


6
I, 200
140
415
19,679

17,750,000
4, 900,000
40,800,000
172,000,000


feet
feet
feet
feet

cubic yards
cubic yards
pounds
pounds


34,985 feet
600 feet
300 feet
45 feet
29,700,000 cubic
21,950,000 cubic
51,650,000 cubic


yards
yards
yards


2,437,000.cubic yards


623

1,671
349
2,6143
7,000 to 8,000

10.35 miles
71,837,000 cubic yards


$277,000,000










Canal Zone and Existing Canal


LOCATION OF PANAMA CANAL
Due south of Pittsburgh, Pennsylvania
North, 8 551, to 9 25' from equator
Distance to New York
Distance to San Francisco


AREA OF CANAL ZONE
Land
Water
Total


CLIMATE
Temperature, average daily maximum, Pacific Side
Temperature, average daily minimum, Pacific Side
Average relative humidity
Annual rainfall, Pedro Miguel
Average rainfall, .Atlantic Side


PRESENT CANAL
Length
Minimum channel width
Maximum channel width
Minimum channel depth
Number of lock chambers
Locks, length
Locks, width
Locks, depth


GATUN LAKE
Surface elevation
Surface area :
Capacity


EXCAVATION, ORIGINAL CANAL
Excavated by the French, total
Excavated by the French, useful in present Canal
Excavation in the original Canal prism, to date
of opening
Auxiliary excavation
Grand total excavation, 1904 to 1939, inclusive


Original cost of the Panama Canal (Net)


1,974 miles (nautical)
3,245 miles (nautical)



361.86 square miles
190.94 square miles
552.8 square miles


87.3
73.10
83%
80.9 inches
124.1 inches


51 miles
300 feet
S1,000 feet
40 feet
12
1,000 feet
110 feet
40 feet


85 feet
163.5 square miles
183, 172 million cubic feet



78,146,960 cubic yards
29,908,000 cubic yards


208, 027,540
76,644,655
419,467,555

$380,000,000


cubic
cubic
cubic


yards
yards
yards










Canal Traffic by Fiscal Years 1915 to IGWO


Fiscal Year
Ended
June 30--


1915
1916
t917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940


Number of Panama Canal
Transits Net
Tonnage (31


1,058
S724
1,738
1,989
1,948
2,393
2,791
2,665
3,908
5, 158
4,592
5,087
5,293
6,253
6,289
6,027
5,370
4,362
4, 162
5,234
5, 180
5,382
5,387
5,5214
5,903
5,370


3,507,000
2,212,000
5,357,000
6,072,000
5,658,000
7,898,000
10,550,000
10,556,000
17,208,000
24,181,000
21,134, 000
22,906,000
24,245,000
27,229,000
27,585,000
27,716,000
25,690,000
2 I, 842,000
2 I, 094, 000
26,41 0,000
25,720,000
25,923,000
25, 430,000
25,950,383
27, 170,007
24,144,366


Tolls


$ 4,366,747.13
2,403,089.40
5,620,799.83
6,428,780.26
6,164,290.79
8,507,938.68
S11, 268, 681.146
11, 191,828.56
17,504,027.19
24, 284,659.92
21,393,718.01
22, 919,931.89
24,212,250.61
26,922, 200.75
27,11 I, 125.47
27,059,998.94
24,624,599.76
20,694,704.61
19,601,077.17
24, 047,183.144
23, 307,062.93
23, 479,114.21
23, 102, 137.12
23,169,888.70
23,661,021.08
21,1441, 675.36


Total 109,787 493,385,756


4714,191,533.27 526,089,691


(1) Canal opened to traffic August 15, 1914
(2) Canal closed to traffic approximately 7 months of fiscal year
by sli des
(3) Panama Canal net tonnage prior to 1939 are estimated figures
based on revised measurement rules which became effective
March 1, 1938


Tons of
Cargo


4,888,400
3,093,335
7,054,720
7,525,768
6,910,097
9, 372, 374
11,595,971
10, 882,607
19,566, 429
26,993, 167
23,956,549
26,030, 016
27,733,555
29,615,651
30,647,768
30,018,429
25,065,283
19,798,986
18, 161, 165
24,704,009
25,309,527
26,505,943
28, 108,375
27,385,924
27,866,627
27,299,016





















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