We all complain about the inconveniences of our jobs from time to time. And in construction those inconveniences can be worse than most. Long hours, exposure to the weather, deadline pressure, months away from families - there are plenty of things to grumble about. But the next time you feel a complaint coming on, remember the workers on the Changuinola Hydroelectric Project in the depths of the Panamanian rainforest. They have to cope with all of the above - as well as scorpions creeping into lodgings, poisonous snakes dropping onto them from trees, black panthers, pumas - even "killer bees."

Close to the border with Costa Rica and 600km (370 miles) from the capital Panama City lies Changuinola, a fishing village named after the River Changuinola besides which it is built. Home for centuries to Indian tribes, the only previous outsiders to have ventured to this dense rainforest were banana farmers and adventurous tourists. But now Panama is changing. The substantial expansion of the country's famous canal is just one part of a building boom that is increasingly putting the Central American country onto the map and turning it into an important economic and tourist destination.

But this expansion is putting pressure on the country's infrastructure, not least its power generation capability. To overcome this, an ambitious plan is being put in place to harness the power of the country's rivers to provide a sustainable electricity supply. The Changuinola Hydroelectric Project Panama is the flagship scheme. A 90m (295ft) high roller compacted concrete dam, which will be 545m (1,788ft) wide and hold back a reservoir of 122 million cubic meters (159 million yd3) of water, and channel it down a 3,952m (12,970ft) long concrete lined headrace tunnel to a main 207 MW turbine. The project, when completed, will deliver 939 GWh of power a year.

AES Changuinola, a subsidiary of US-based AES Corporation, owns the project, with a consortium comprising of French based Alstom and two Danish companies E Pihl & Søn, and MT Højgaard. About 1,000 people have been at work on the project since it began in 2007, and 300 operators are allocated to 150 pieces of mobile equipment. Volvo is the main equipment provider on the project, supplying over 34 machines through its local dealer Commercial de Motores SA. The Volvo fleet consists of 16 A35D articulated haulers, 11 wheel loaders, two Rototilt-fitted EW180C wheeled excavators (for embankment grading), one 70 tonne EC700, a G710B motor grader and a BL60 backhoe loader.

With a completion date set for 2011 machine reliability is of paramount importance. The entire Volvo fleet is protected by a "Gold" customer support agreement - this takes responsibility for the repair and servicing Volvo also guarantees the fleet's mechanical availability will not dip below 90% between the machine hours of zero to 8,000 hours. In actual fact, total fleet availability after the first year of operation was 98.31%.