Oria Medio WWTP in Aduna, Guipúzcoa


On March 18th 2008, the Guipúzcoa Provincial Government awarded the contract for the Design, Construction and Commissioning of the Oria Medio Waste Water Treatment Plant in Aduna to the EDAR Aduna consortium (Construcciones Amenabar S.A., Acciona Agua S.A.U.). The work was successfully completed in July 2012.

The plant was inaugurated at the beginning of May and treats a flow of 28,080 m3/day, which increases in rainy periods to a maximum of 128,000 m3/d. It serves a population equivalent of 115,317.

The WWTP is located in the municipality of Aduna, in a meadow situated on the left bank of the River Oria, near where Aduna meets the municipalities of Villabona and Andoain.

The infrastructure has a total surface area of 20,000 m2 and has four main buildings: the pretreatment building, the sludge building, the biological treatment aeration building, and the control building. The latter building includes both the control room and the laboratory.

The infrastructure is made up of nine general interceptors and numerous secondary pipelines. The interceptors have a combined total length of 33.8 km and required investment of €61 million. Uralde is the latest of the 13 large-scale treatment plants that form part of the territorial network.