Facts
The dispute is between a consortium of six construction companies (the Consorzio Galleria San Bernardino) and the Canton of Grisons. The consortium was entrusted with the execution of the construction work for a road section according to a lump-sum and unit-price contract. The consortium is requesting an increase in the agreed price, invoking Art. 373 para. 2 CO and Art. 5 no. 1 of the conditions for the construction of national roads (BBN), on the grounds that the execution of the work has been excessively difficult due to extraordinary circumstances.Considerations
The Federal Court considers that the conditions for the application of Art. 373 para. 2 CO are met. The unit prices and lump-sum prices had been precisely determined in advance in the contract. Furthermore, the execution of the work has been excessively difficult due to extraordinary circumstances that were not foreseeable and could not be attributed to the behavior of the consortium.
Art. 5 no. 1 BBN does not constitute an autonomous provision, but simply specifies which costs are covered by the lump-sum and unit prices, as well as the aggravating circumstances already taken into account. This…