Aranjuez WWTP (Madrid)

The Spanish National Water Quality Plan sets out a number of measures that seek full compliance with Directive 91/271/ EEC on urban wastewater treatment. The Plan also seeks to contribute to achieving the good ecological status proposed by the Water Framework Directive for the year 2015. This Directive is transposed into Spanish law through Royal Decree Act 11/1995, of December 28, which establishes the regulations applicable to urban wastewater treatment, and Royal Decree 509/1996, which develops on the previous Royal Decree. The former Royal Decree was subsequently reformed to give rise to Royal Decree 2116/1998



Canal de Isabel II, S. A., through its Department for the Construction of Wastewater Treatment and Reuse Facilities, is the developer of the Aranjuez WWTP. The plant was built by a consortium composed of GS Inima and Asteisa, and technical assistance was provided by Técnicas Reunidas, S. A.

The Aranjuez WWTP is managed by Canal de Isabel II S. A. and discharges into the River Tagus. It is located in the southeast of the municipality of Aranjuez. The plant went into operation in 2001, with an average treatment capacity of 21,000 m3/day and a population equivalent capacity of 157,000.

Although the theoretical capacity of the original Aranjuez WWTP had not been exceeded in terms of flows (21,000 m3/day), the increased pollutant load with respect to the design scenario and the more stringent requirements of Directive 91/271/EEC on urban wastewater treatment (reformed by Directive 98/15/CE), which seek to help achieve the good ecological status proposed by the Water Framework Directive, made it impossible for the plant to achieve compliance with the parameter set for Nt in the treated effluent.

As a result, Canal de Isabel II decided to undertake the necessary actions to ensure compliance with the targets set in the National Water Quality Plan.

Plant Report published in: #61 FuturENVIRO June 2019