Consorcio de Aguas Bilbao Bizkaia approves €251.5 M investment in supply and sanitation infrastructure

€113.6 M will be invested in sanitation and €131.2 M in the supply network

The General Meeting of the Consorcio de Aguas Bilbao Bizkaia (Bilbao Bizkaia Water Consortium), held yesterday at the Euskalduna Palace in Bilbao, has given the green light to its water supply and sanitation investment programme for the period 2021 – 2024. The Consorcio de Aguas will invest 251.5 million euros in the period to 2024 – an average of 63 million euros per annum – mainly in new infrastructures to guarantee the quality and quantity of water supplied, and to improve the ecological status of water bodies by reducing the pollutant load of discharges. The programme will also see investment in other complementary actions associated with the expansion and optimisation of processes and energy efficiency. Of the total amount allocated, 113.6 million euros will be devoted to sanitation and 131.2 million euros will be invested in supply infrastructures.

A total of 162 actions will be executed throughout the territory (58% associated with supply and 42% with sanitation). 41 of these actions are now underway and contracts for 37 will be awarded or put out to tender in the current financial year. Most of the actions will involve an investment budget of between 200,000 and 1 million euros (44.4%). Five major infrastructures will require investment of over 10 million euros and two will have a budget of more than 20 million euros. Under the terms of an agreement entered into with the Consorcio de Agua Bilbao Bizkaia, the Provincial Council of Bizkaia will finance 7.9% of the total investment programmed for the period 2021-2024. The remainder will be financed with the Consorcio’s own resources from water supply and sanitation charges, supplemented by available surpluses. Despite sustained investment over time, the water sector still requires huge investments to continue improving and adapting to increasingly stringent regulations.


Within the 30.5 million euros allocated for supply during the 2021 financial year, 6.7 million euro has been earmarked for the second phase of the Enkarterri ring main, which will allow the joint management of the Zadorra – Venta Alta and Ordunte – Sollano systems through the creation of a ring that will reinforce the guarantee of supply to the Metropolitan Area of Bilbao in emergency situations. The first phase between Las Carreras (Abanto) and El Arenao (Sopuerta) was completed in 2018.

The section currently under construction will connect the Jarralta branch line (Sopuerta) and the Abellaneda reservoir, on the border of the municipalities of Sopuerta and Zalla. This is a major project that will benefit the whole of this historic territory and it will require additional investment of 9.7 million euros in 2022 and 2023. The investment programme also includes a number of actions in the Enkarterri region to improve the supply to the town of San Pedro de Galdames (1 million euros) – and to renovate and extend the infrastructures of the Ordunte – Sollano system, with a budget of over 3 million euros for the entire period.

Investment of 1.6 million euros is to be made in Durangaldea to complete a pipeline between the Garaizar and Abadiño DWTPs for the purpose of guaranteeing the quality of water supplied in the area. This work is currently underway and the pipeline is expected to be in operation in 2022. Finally, of particular note is the investment of over 8 million euros in the period to 2022 for the replacement of the activated carbon filtration system at the Venta Alta DWTP. This will provide the facility with innovative systems and full capacity to make water from the Ibaizabal River – or any water of poorer quality at source – drinkable with full guarantees in the case of necessity.


A total of over 17 million euros will be invested in initiatives related to sanitation in 2021. The most significant amount, over 4.4 million euro, will be allocated to ongoing work on the Galindo stormwater tank, which will also see investment of 11.1, 15.4 and 10.6 million euros in 2022, 2023 and 2024, respectively. Stormwater tanks are amongst the priorities of Aguas Bilbao Bizkaia in order to achieve compliance with Directive 92/271/EEC on wastewater treatment. These large underground tanks are designed to collect part of the overflow from sewers at times of heavy rainfall, which is normally the water with the highest pollutant load. When the rains stop and the inflow to the treatment plants returns to normal levels, the water collected is gradually incorporated into the treatment process. In this way, stormwater tanks reduce the amount of wastewater discharged into the environment without adequate treatment.

The 2021 investments in sanitation also include several smaller but important actions to improve wastewater management in isolated and rural areas. Also of note is an allocation of 1 million euros for the incorporation of the sewage network of Arratia and the area served by the Bedia WWTP into the Nervion-Ibaizabal interceptor sewer. The most significant work on this project will take place in 2022, with further investment of over 2 million euro.  Although most of the investment is earmarked for new infrastructures, it is important to note that 29.7% of the budget corresponds to initiatives for the upgrading and enhancement of processes and facilities.

These actions are essential to maintain the quality of the service, and allocations for them will increase progressively as the depreciation life of infrastructures comes to an end.  In this financial year of 2021, 1.3 million euros has been allocated to the extension and upgrading of the Muskiz WWTP, work which will entail overall investment of 10.8 million euros. Crucially, the installation of new technology in the biological treatment process will not interrupt the operation of the plant at any time, meaning that the effluent from the plant will continue to meet the discharge parameters required under current legislation.