The bridge located at K.P. 0+050 of the NA-7063 regional road, at the access to the municipality of Eguíllor in the Community of Navarra, serves as a crossing to the NA-7063 over the Arakil river. Its original structure was formed by four limestone vaults, but only span V1 preserves this initial typology. In span V2, the vault has been replaced by a ribbed reinforced concrete slab, while spans V3 and V4 have vaults of mass concrete or weakly reinforced concrete from past interventions.

The structure had severe resistance problems in the ribbed slab of span V2, which indicated its inability to cope with current traffic loads. In addition, there was evidence of seepage from the deck and backfill in the form of patina, efflorescence, outcropping vegetation and scarcity (or even absence) of material between the joints of the masonry pieces in the rest of the bridge.

On the other hand, the existing roadway was very narrow, providing a single lane for both directions. This, together with the deficiencies in the pavement: potholes and ruts and the existence of a non-approved containment system, made it necessary to carry out an integral intervention on the structure that would be respectful of the original structure and would not require total traffic cuts.

The solution adopted was the construction of a new bridge attached to the existing one, which is materialized with a new mixed deck that will be connected in continuity with the existing one, to which a distribution slab is executed. In this way, it was possible to provide the structural assembly with a width of 10 meters, allowing traffic to travel in one lane in each direction.

The old structure is also being worked on, repairing the durable deterioration with superficial repairs and rehabilitations, and replacing the reinforced concrete span with a deck similar to that of the new structure.

All the actions were also conditioned by the water level of the Arakil River during floods, which made it necessary to design a strict edge deck.