Maintaining Cambodia’s dilapidated rural roads is a virtually impossible task because of problems associated with gravel roads, a British engineer asserted during a conference in Phnom Penh Thursday.
“There’s no way we can maintain these roads,” said engineer Robert Petts, who said that other road surfacing materials must be explored. “It’s just not feasible.”
Participants at the conference, sponsored by the UN International Labor Organization and the Institut du Cambodge, agreed that rural roads are essential for pulling villagers out of poverty by aiding access to schools, clinics and markets.
A recent study found that incomes and school enrollments jumped soon after roads were improved, said Minister of Rural Development Ly Thuch, whose ministry oversees rural roads.
International donors supply the loans or grants for building most of Cambodia’s roads. But they typically expect the cash-strapped government to pay maintenance costs, he said. The government did not have any rural road maintenance budget at all until 1999; now the budget is only about $500,000 a year.
“We find that we must pay back the money to build the roads, and at the same time the roads are deteriorating,” he said.
Gravel roads, also known as laterite, are among the cheapest to construct and so have been the most commonly used in the developing world for the past 30 years, Petts said.
But they present a variety of problems, he said. Sometimes gravel is mined from environmentally sensitive areas, or must be hauled from a long distance away. Gravel supplies run low, increasing costs. Contractors are often tempted to skimp on gravel or use gravel that is too fine or coarse.
Cambodia has high rainfall, which tends to wash gravel away; it also has a long dry season, so much of it wastes into dust, covering homes and choking lungs. New gravel must be added to the road as part of routine maintenance, or the road must be rebuilt. A typical gravel road in Cambodia costs about $1,500 a kilometer per year to maintain, said Samer Fayadh, a researcher working with Petts.
By contrast, a road made of earth can be much cheaper to build and maintain, Petts said. The road is simply raised above flood level and shaped with a slope, or camber, that guides water to the side. The road must still be reshaped periodically so it does not trap water, however.
Other ways of building roads may be more expensive than gravel to construct, but cheaper in the long run because of decreased maintenance, Petts said. They also use materials that are local, plentiful and cheap.
In Kompong Cham province, the Swedish government is funding a trial road surfaced with the basalt found in the boulders common throughout the province. And in Siem Reap province, a stretch of road has been built with concrete reinforced with bamboo, rather than the more typical steel.
The Swedish-funded experiments and British-funded road research should help convince government officials and international donors to look at a wider variety of road-building methods, Petts said. “We’re on the brink of a radical change here,” he said.