
January 5, 2012
Madden Dam and Lake Alajuela
The United States took over the task of construction of the
Panama Canal on may 4, 1904, after quite a debate as to where would be the best
site for this project, even after the French had already started construction in
Panama. The U.S. considered five routes before deciding to continue the
work the French had already begun. As you can see below, these routes
included (1)through the narrowest point in Mexico, (2) through Nicaragua, (3)
the French route through Panama, (4) a second route through Panama going roughly
from the Gulf of San Blas to Chepo and (5), through Colombia using the Atrato
River.
Map: US Army Corps of Engineers
The French had considered several alternatives canal designs
including their initial effort for a sea level canal and, later, on their second
attempt, a locks canal. With greater engineering information, the U.S.
abandoned the French design and proceeded with a locks design based on a large
lake 85 feet above sea level. The French sea-level design suffered greatly
from the large volume of excavation required and from flooding that would have
occurred along the Chagres River. By constructing a dam (Gatun
Dam) near the mouth of the Chagres, the combined effect of reducing
excavation and mitigating flood impacts was achieved at the cost of constructing
the locks.
The Panama Canal watershed is 1289 square miles drained by six
major rivers of which the Chagres is the largest. Five major stream gages
keep track of the flow from these rivers into Gatun Lake. These stream gage
locations, shown in the map below, are: the Gatun River at CIENTO; the Boqueron
River at PELUCA; the Pequeni River at CANDELARIA; the Chagres River at CHICO;
the Trinidad River at EL CHORRO; and the Ciri Grande River at LOS CANONES.
Map: US Army Corps of Engineers
When the canal operations began in 1914, it became evident that,
for water management purposes, another dam was needed. And it had to be
above Gatun Lake. Thus, on October 13, 1931, construction on another dam
was begun up the Chagres near the location of a little town called
Alajuela. The dam was named Madden, after U.S. Congressman Martin B.
Madden, Chair of the House Appropriations Committee, who played an
important role in support of the project. The dam would not only help
control the tremendous floods of the Chagres, but also hold water in reserve for
periods when traffic through the canal was at its highest point. And
additional benefit was the hydroelectric power it generated for use in the
operation of the canal.
Madden Dam is located 250 feet above sea level and retains 29
million cubic feet of water. It was constructed by the engineering companies of
W.E. Callahan and Peterson, Shirley & Gunther of Omaha for $4,047,407
(Note 1) which was a lot less than had been estimated by the Isthmian Canal
Commission. The design and construction work was under the direction of
E.S. Randolph, who stayed at the job site through out its construction.
The contract was signed by General Burgess, who was the Governor of the Canal
Zone at the time.
Madden Dam and what is now called Alajuela Lake.
Photo by Panama Canal Co.
The resulting lake was called Madden Lake for many years but,
eventually, this was changed to Alajuela Lake. This lake has a perimeter
of 189 miles. The dam is 930 feet long and rises 220 feet from its
foundation. Up to 893 persons, divided almost evenly between the
contractor and the Canal Zone government, were employed during its peak
construction period. Completion of the dam was accomplished on February 5,
1935, five months ahead of schedule and was hailed as another triumph of U.S.
engineering in the history of the Canal. The Canal Zone government
proceeded to build a concrete paved road 12-1/2 miles long connecting the new
dam to the town of Summit.
Madden Dam in present days. Photos: Panama Canal
Museum
Madden Dam shortly after completion. LIFE
magazine.
Madden Dam is maintained and operated by the Panama Canal
Authority. This large reserve of water has lived to its expectations
providing water to (1) help maintain water levels necessary to operate the canal
during the dry season, (2) control flooding of the Chagres and (3) providing
hydroelectric power for the area.
Sources: Dr. Alonso Roy, M.D., Escritos Historicos de
Panama; Timothy Davis, Sioux Falls Travel Examiner, 5-18-10;
NOTE 1: Dr. Roy states that the contract for the dam was $4,047,407. However, industcards gives a figure of $$10.6 million.
- Luis R. Celerier
Longview, Texas