More than two-and-a-half centuries ago, the French explorer Charles Marie de la Condamine crossed the continent of South America. It took his expedition four years to wind its way over the Andes and through the Amazon jungles to reach the Atlantic Ocean. Within this decade, the same trip will take four days.

Engineers are currently working on a massive $1.3-billion InterOceanic Highway project slated for completion by 2009. The finished route will create the first paved roadway connecting the Atlantic and Pacific oceans on the South American Continent itself.

“This is a multi-country effort to create an infrastructure that will be the backbone of economic integration for the region,” says Peru’s Minister of Transportation and Communications, Veronica Zavala. “It makes sense not just for matters of transportation it makes sense in a much bigger picture for everyone involved.”

The paved highway has been completed through Brazil with the border crossing at Iñapari marking the final point of the project in Peru. Peru is counting on the road as a means of opening up its long-neglected interior for development. Brazil is looking for access to Pacific ports.

It’s one of the most ambitious projects ever attempted in Peru, Zavala says.

“This area has some of the most difficult geography in South America to overcome with the Andes and the jungle,” she says. “It is an incredibly complex project.”

A traveler through Southern Peru can wake up in the harsh chill of the high Andes in the early morning and spend the evening sweating it out in a jungle hut. That poses a legion of difficulties including extreme elevations, incessant downpours and dramatic geography.

Parts of the existing unpaved road are impassable in the rainy season.
Photo by C.J. Schexnayder/ENR

Success will require a delicate balancing act of planning, logistics and luck, says Wilhelm Funcke, the head engineer for Irsasur, the concessionaire constructing a 300-kilometer section of the road.

"We have to evaluate what is the best solution in each specific case and then make up the cost elsewhere," he says. "It's a ongoing process that we will have to watch carefully over the entire project."

The Highway

The InterOceanic highway project is divided into five sections, or “Tramos.” The three currently under construction consist of upgrading more than 1,000 kilometers of the existing two-lane unpaved road that was built more than three decades ago. The route runs through the Peruvian Andes and the jungle to Brazil.

In 2004, two sections that make up approximately 700 kilometers, Tramo II and Tramo III, were awarded to ConIrsa, a consortium made up of Brazilian construction giant Odebrecht and several Peruvian firms. The 300-kilometer Tramo IV was awarded at that same time to InterSur, a consortium comprised of a similar group of Peruvian companies led by the Brazilian construction firm Camargo Correa.

Two other sections that entail upgrading more than 1,500 kilometers of existing paved roads that lead to the coastal cites in Southern Peru are expected to be awarded in the next few months.

The existing unpaved road is difficult to traverse due to obstacles such as hairpin turns, towns built on the road and roadway decay. In addition, the route has no drainage and only limited bridging. With inclement conditions – including the November-to-April rainy season – many sections simply become impassable.

The lack of maintenance limits the amount of useful roadway for the construction effort and almost all of it will be covered to build the new highway. Despite that, the one advantage of the crude road is that since approximately 90 percent of roadway already exists there is a reduced need for land clearance and limited environmental impact.

When completed, the new highway will be a total of 7.4 meters wide with two lanes of 3 meters and a shoulder on each side. The sub-base is 15 centimeters thick and consists of lime mixed with prepared material. It is topped with a 15 centimeter base of a cement and soil mix.

The paved roadway itself will be two layers of asphalt a total of 7.5 centimeters thick. The road surface will have a 2.5 percent incline to permit runoff. Extensive drainage will be constructed as well although the exact type will vary from location to location as conditions require.

Officials with both Conirsa and Irsasur say the key to handling the construction challenge was organizational aspect of the job. The sheer scope of the work that engineers from Odebrecht and Carmargo Correa spent months preparing every aspect of the project before beginning the actual work.

Conirsa spent six months on advance planning alone, says Daniel Villar, the Odebrecht engineer who headed the highway project for Conirsa through its initial phase.

“Logistics are the key to making a project of this scale succeed,” he says.

To do that, Conirsa effectively divided itself into two companies that are handling the two sections independently. While the heads of those two entities are in constant contact and meetings between the engineers are encouraged, the two jobs have been organized independently.

The Conirsa office in Lima then concentrates on handling the governmental and regulatory issues for both jobs instead of micromanaging the oversight of each highway portion.

Irsasur followed a similar patter with its one section. Camargo Correa worked for years in anticipation of the InterOceanic Highway project says Marco de Moura, the head of the company’s Peru office.

“So when we got the contract had the people with the experience to build roads under every condition we would be working under,” de Moura says. “So then our main responsibility was to put it all together and make it all work as a whole.”

Arranging the financing posed one of the most important initial hurdles for both Conirsa and Irsasur. Each section is part of a 25-year concession that will be paid back through tolls when the construction is completed. Final design of the roadway also took much of the first year of work to complete.

The new highway follows the old unpaved roadway where possible.
Photo by C.J. Schexnayder/ENR

“In many case the initial reports provided for the job were seriously out of date and incorrect,” Funcke says. “When we got out there to do the preliminary planning work what we encountered was significantly different that what we were told was there.”

Due to the remote locations of most of the work, the companies are depending on a camp system and mobility of the work crews for the construction. On Tramo III, for example, Conirsa has established two primary camp sites at either end of the road – one in Iberia an hour from the Brazilian border, the other in Mazuko close to the Inambari Bridge.

Each camp is a self-sufficient semi-permanent locale with dormitories, administrative offices, and industrial areas. Satellite telephone and direct links connect the camps to each other and Lima. Labs at each camp are constantly conducting tests on the roadway material and processes. Machine shops doing the major work on the roadway equipment are housed at these locations as well.

Smaller camps have been established on the route for specialized work such as gravel production. On Tramo II, a large facility has been built at Ocongate for the rock crushing and asphalt production.

From the time the bids for each section were awarded, each company has been responsible for roadway maintenance along their specific section. Much of the preliminary work included shoring up the substandard water crossings, widening the narrow sections and keeping the roadway passable. This maintenance effort is also integral to the construction effort, officials say.

The Andes Mountains

Perhaps the most formidable obstacle to the construction is the Andes. The roadway reaches 4,700 meters in one section of Tramo II and almost 5,000 meters at the highest point on Tramo IV.

That elevation creates a battery of complications, particularly the paving. The frigid alpine conditions above the 3,000 meter mark severely limit the ability to pave on a regular schedule.

"The ground temperature simply is not warm enough to allow us to pave properly," says Hildalgo García, the engineer in charge of the Tramo II industrial plant in Ocongate.

At maximum capacity under ideal conditions, Tramo II asphalt plant can produce 180 metric tons an hour. That amount is slashed to between 120 and 100 metric tons an hour due to the 3,750 meter elevation, García said.

Asphalt plant's 3,750-meter elevation creates operational issues.
Photo by C.J. Schexnayder/ENR

That severe limitation of productivity is an issue for all the equipment used at the higher altitudes. Irsasur officials say that in some places they have to use twice as many machines to get the same amount of performance of one in more normal elevations.

“At this altitude the oxygen is very thin,” García says. “We compensate by regulating the oil pressure as well as the flow of air being injected into the engines. Keeping that balanced gives us proper combustion.”

The high altitude also creates manpower problems. Workers who are not acclimated to the elevations have severe limits on the hours they can work in the field. Irsasur required all the administrative personnel working at the high-altitude camps for Tramo IV to take an extensive physical before they were allowed to accept the assignment.

Conirsa has also been aggressive in training efforts, increasing the number of local workers who can operate the large machinery and other technical tasks needed on the construction effort, Villar says.

This problem is partially overcome by making an aggressive effort to hire local workers for the work crews but many of those with technical and administrative skills must come from the urban areas of Peru – located on the coast.

The Amazonian Rainforest

At Puerto Maldonado on the Madre de Dios River, the geography follows the classic Amazonian rain forest pattern. It is a relatively level terrain but the frequent small waterways that criss-cross the region constantly create obstacles for regular traffic and impassable obstacles when they flood during the rainy season.

In the Amazon, the single biggest headache is the rainy season, where precipitation is measured in feet instead of inches. The season typically lasts from November through April; as much as 80 percent of the annual total of rain falls then.

“We have to be very productive and work rapidly to take advantage of the natural window of opportunity we have in the year,” Felipe says. “When there is sun and no rain we have to get as much work done as we can.”

Conirsa engineers are working to widen that window as much as possible as well. One innovative strategy has been to construct tents to pave under during the rainy season. These will allow a limited amount of production to continue during the half of the year roadwork is normally forced to halt due to the deluges.

The regular condition of the road also creates headaches for the construction effort.
For example, the bridges – where they even exist – typically are limited to only 18 tons. That makes it impossible to use trucks with more than two axels for transporting equipment, fuel and material. All these supplies have to be broken down and moved in on smaller vehicles.

And, to make matters worse, no bridge exists at the formidable Madre de Dios River forcing Conirsa to move all the resources across by ferry.

The portions of the road in the mountainous jungle regions pose formidible engineering challenges.
Photo by C.J. Schexnayder/ENR

As the roadway drops out of the austere elevations on the eastern slopes of the Andes it quickly enters one of the most beautiful portions of the roadway and one of the most difficult for the construction efforts.

This area is known as the “eyebrow of the jungle” a region between 2,500 and 1,000 meters marked by lush vegetation, steep slopes and almost daily rainfall during half of the year.

The higher elevations of these sections are marked by scores of switchbacks in the highway. These give way to the uncertain terrain of the river valleys the road follows out of the mountains.

The handful of bridges that do exist are military-style Bailley bridges that are more than four decades old. All will have to be replaced, Funcke said.

These close conditions and steep slopes will require extensive preparation work. Multiple levels of terracing built above the roadway as well as supports below are needed throughout these sections. The abundance of runoff also places a premium on drainage works and bridges.

The complex geographical hurdles are complicated further by the need to keep the highway operational. Conirsa, for example, has begun shutting down the road through the daylight to do their work and opening it for traffic. The intermittent schedule as well as the additional time needed each day for cleanup severely cuts into their rate of progress.

For Irsasur, some of the sections might have to be completely closed for some period of time due to extensive blasting that will be needed. They are working with local authorities to find alternative routes but there are very few options in the region.