WMOD00532

• Title: The Rain Stimulation Campaign in Panama Summer 1983
• Date: 6/1/1984
• Weather Modification - Doc Type: Report

2. The Water Crisis in Panama

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During the eleven months, from October 1982 through
August 1983, unprecedented drought prevailed over a
large area of Central America and the Caribbean Sea.
Recent studies have suggested a connection between
the drought and anomalies in the Southern Oscillation
(a seesaw of atmospheric pressure between thE~ Indian
Ocean and the southwest Pacific) and occurrence of
"EI Nino", the invasion of warm equatorial water into
the domain of the Humboldt Current off Peru and
Ecuador. For the Panama Canal and Panama City, this
widespread drought caused the most severe water
crisis since the canal began operation in 1914.

Normally, the rainy season months of October and
November leave Gatun and Madden Lake with plenty
of water to keep the canal in full operation through the
winter dry season until the normal start of the next
rainy season about mid-April. The water is used to fill
the locks as ships pass through. Water drawn from
Madden Lake, besides providing the municipal supply
for Panama City, generates hydroelectric power as it is
discharged into Gatun Lake to maintain the wat'2r level
there. When Gatun Lake has more water than needed
for the locks, hydropower is generated at Gatun Dam.

The winter dry season of 1982-83 began very early, in
mid-October, and did not break until early May (:fig, 1).
Furthermore, the dry season was exceptionally severe.
November, December, and February set new records
for dryness; January was the third driest on record, and
March the second driest. The 6-month span, November
through April, was the driest on record, with only 43
percent of normal rainfall compared with 45 percent for
the previous driest in 1976-77. As conditions worsened
and it became likely that the level of Gatun Lake would
continue falling, the Panama Canal Commission had to
advise shippers well in advance that restrictions would
be placed on the draft of ships passing throu!~h the
canal. Eventually the lake fell so low that draft had to be
reduced to 3.5 feet less than normal. The consequence
was a severe immediate loss of operating income and
the prospect of future loss of business if shippers were
to shift permanently to other routes. Added to this
concern was the loss of hydroelectric generation and
the need to buy power elsewhere.

The drought likewise affected the ability of the Instituto
de Recursos Hidraulicos y Electrificacion (lRHE) to
su.pply electrical power to Panama City. This primarily
comes from a hydroelectric plant at Lake Bayano,
about 40 miles east of the city. As the level of this lake
fell, rotating brownouts were instituted as a conser-
vation measure.

On the occasion of the previous worst drought, in 1977,
tl1<2 Panama Canal Commission had given consideration
to rainfall stimulation but rejected it because of doubts
expressed about its safety and effectiveness. This time,
as the crisis mounted, the Chairman of the Commis-
sion asked for advice from the U.S. Department of the
Interior, Bureau of Reclamation in Denver, Colorado,
whose Division of Atmospheric Resources Research
had accumulated nearly 20 years of research exper-
ience looking toward useful applications of
weather modification to the problems of water re-
sources management. Because IRHE (an autonomous
agl2ncy of the Republic of Panama) was also concerned,
it joined with the Panama Canal Commission in re-
questing consultation.

This request for advice brought the immediate dispatch
of an experienced weather-modification scientist from
the Bureau to Panama. The feasibility of stimulating
pnlcipitation under the weather conditions prevailing in
Panama was reviewed. Considering that the need for
immediate relief and likely benefits outweighed the
risks and uncertainties as to the magnitude of a rain
stimulation effect, the Panama Canal Commission
decided to proceed with the emergency cloud seeding
operation. Since all cloud seeding would be done over
the territory of the Republic of Panama, and since
under Panamanian law, the Ministry of Agriculture was
designated as the licensing agency for any cloud
seE~ding over this territory, a rapid round of consul-
tations took place with representatives of the Ministry
of Agriculture and its environmental agencies. Approval
was quickly obtained and, within a few days, agreements
were signed between the Commission and IRHE, and
between the Commission and the Bureau of Reclama-
tion, for conducting an immediate rain-stimulation
operation. These agreements are reproduced in the
appendix portion of this report.

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