The Artxanda Tunnels are a varied road system with three routes forming a triangle. Two of them, La Salve-Txorierri and Ugasko-Txorierri (toll fee) join the centre of Bilbao to Dual carriageway BI-637 (Txorierri corridor) speeding up access to the airport of Bilbao and the municipal districts on the right hand bank of the Nervión River. The third, Ugasko-La Salve, is a by-pass to the city of Bilbao between the quarters of Begoñ

By upgrading the Venta Alta Sewage Works' sludge treatment plant both the treatment capacity and the flexibility of operation were improved; the job of maintaining the system was also made easier.

The Kadagua Interceptor, lower reach, forms part of the infrastructures of the Co-ordinated Wastewater Plan for the Greater Bilbao Region. The interceptor conducts to Galindo Wastewater Treatment Plant the wastewater generated in the urban and industrial areas of the municipalities of Bilbao, Barakaldo and Alonsotegui, which used to be discharged directly into the river.

The purpose of the project is to collect the urban wastewater from the Rentería and Kamiñazpi neighbourhoods and transfer it to a pumping station, from which it will be impelled to Ondarroa treatment works.

The work consisted of diverting San Martín brook to guard against flooding in Bermeo town centre.

The diversion re-routed part of the flow in the brook before it enters the town centre on its way to the sea.