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Connecting Landlocked Developing Countries to Markets
moves on, old habits resume, and little is changed. In very few countries is axle load enforcement anything more than spasmodic and intermittent. These observations apply to the enforcement of axle load limits to all trucks, not just those in transit, but the overloading of transit trucks is seen as more pernicious than that of trucks conducting domestic business. In contrast, a more rational response in economic terms is to allocate additional funds for strengthening pavements where overloaded transit trucks are believed to do the most damage and then to charge the transit trucks for this additional expense. For operators, the short-term economies of scale of overloading can be compelling, and they have strong commercial incentives to load their trucks to their physical capacity. Capacity not used is lost—it cannot be stored for sale later on. The short-term gains in revenue are directly proportional to the additional freight carried, whereas the cost to the operator in terms of additional truck maintenance or shorter vehicle life do not become apparent for some time and are often lost in the overall costs of the business. Unless the truck operators are charged for the damage the overloading causes to the road pavement, they can completely escape the highest cost of overloading. From a national economic perspective, the total operating costs of all trucks using a road, when added to government expenditures on pavement rehabilitation and strengthening, are lower than the sum of the truck operating and road pavement costs with trucks loaded only to their legal axle load limit. World Bank studies in the 1980s (Harrall and Faiz 1988) demonstrated that on all but the most lightly used roads, stronger pavements were economically justified, because the savings in truck operating costs of carrying more freight outweighed the extra construction or repaving cost. It is routine practice for trucks engaged in international transport to be weighed at the border post of entry. Transport ministries can and do use the same information to verify axle loads. To avoid multiple weighing on a single international trip, the UNECE has designed and is promoting an International Weight Certificate that, if issued by authorities in the country of origin, will be accepted by all border agencies in transit and destination countries. Trucks engaged in international transport are rarely to blame for deterioration of road pavement because they can readily be controlled upon entry into the country. If taxes on diesel fuel are set at appropriate levels, these trucks can be made to pay taxes roughly commensurate with the wear and tear they incur. A rough rule of thumb is that 10 U.S. cents per