In both the short and the long term, the impact of the 1977 treaties on the economy will depend to a large extent on canal traffic. Since 1979, when the treaties went into effect, the amount of canal traffic has stagnated. In 1979 the canal was transited by 13,056 ships by 1984 that nuÍÍÍÍmber had fallen to 11,230--the lowest number in 2 decades. Cargo tonnage also dropped during the same period, from about 154 million to about 140 million tons. Despite the decline in the number of ships and cargo tonnage, toll revenues expanded over the period from US$208 million to US$298 million, because of the toll increase in March 1983.

The decline in canal traffic was in large measure a result of the opening of the trans-isthmian oil pipeline, which carries Alaskan North Slope oil. In 1983 the pipeline diverted 30 million tons of oil from the canal. In terms of Panama's economy, the diversion of oil from the canal to the pipeline did not cause alarm as it was little more than a transfer of services.

Some observers expressed concern that the canal had seen its best days and that it would decline in importance over the long run. Latin American trade, much of which passes through the canal, has stagnated because of prolonged regional recession and balance of payments constraints resulting from the regional debt crisis. Many supertankers and bulk cargo carriers are too big for the canal. Even some smaller vessels sought to avoid the delays associated with transiting the canal. Increased tolls also lowered the demand for canal usage. Many coal and banana producers shunned the canal and shipped to Europe from the Caribbean Basin and to the Pacific Basin from the west coast of Latin America. In addition, the canal faced competition from Mexican and United States land bridges (roads or railroads linking Atlantic and Pacific ports). Standardized cargo containers have made land bridges an increasingly attractive option, even though the distances involved are much greater (the United States land bridge is over 5,600 kilometers long) than across the canal. The concern over the future of the canal was partially allayed by the increase in total canal traffic between 1984 and 1986. In 1986 11,925 ships transited the canal, carrying 139 million long tons of cargo and generating US$321 million in tolls and revenues. In 1987 canal tolls and revenues totaled US$330. The increase in 1986 was due in large measure to increased automobile trade.

In 1982 Panama joined the United States and Japan, the two principal users of the canal, in an agreement to establish a tripartite commission aimed at studying improvements in or alternatives to the canal. The US$20-million study was expected to be ready in 1991. One modest proposal, at a cost of US$200 million, was that of widening the canal at the Gaillard Cut, its narrowest channel. The Gaillard Cut measured approximately 100 meters when the canal opened in 1914, and in the 1960s it was broadened to about 165 meters. The proposal called for doubling the width of the Gaillard Cut. A more extensive plan, at a cost of US$500 million, proposed wi 393dening t the entire canal by 16 meters to allow for uninterrupted 2-way traffic along the waterway. The canal's existing capacity was forty-two vessels a day the less expensive proposal would accommodate fifty ships. The most ambitious plan, however, was that for a second, sea-level canal, which could handle even the largest supertankers without the use of locks. This plan's estimated cost was US$20 billion, considered prohibitive in the light of foreseeable toll revenues. Alternatives to a second canal included an improved railroad system, an express highway for container traffic, and additional pipelines.

Data as of December 1987