The Ministry of the Natural, Rural and Marine Environment, through Sociedad Estatal Aguas del Duero, has picked FCC Construcción to build the second phase of the Payuelos Lower Canal project in León. The canal is worth 80.8 million euro and is to be completed in 36 months. Half the funds for the job are being provided by the 2007-2013 ERDF Cohesion Fund.

The second phase of Payuelos Lower Canal, which is thirty kilometres long, lies entirely in the province of León. The canal starts at a point situated between the towns of Reliegos and Villamarco and hooks up to the first phase of the project, which has already been built, also by FCC. The project ends at El Coso Stream, east of Bercianos del Real Camino, after describing a wide horseshoe whose southernmost point coincides approximately with the town of Castrotierra.

The project runs through the municipalities of Santas Martas, Villamoratiel de las Matas, Santa Cristina de Valmadrigal, Castrotierra, Valverde-Enrique, Vallecillo, Gordaliza del Pino, Bercianos del Real Camino, Calzada del Coto and Sahagún de Campos.

The canal is uncovered and has a trapezoidal cross-section, shrinking to rectangular in the sections where there are constraints on width. Three pools are to be built, with capacities ranging between 200,000 and 350,000 cubic metres, for canal regulation purposes.

The layout includes three major siphons, the 614-metre-long Castrotierra siphon, the 873-metre-long Vallecillo siphon (both 2,600 millimetres in diameter) and, lastly, at the intersection beneath dual carriageway A-3 between León and Burgos, another siphon that is 81 metres long and 3,000 millimetres in diameter.

The maximum flow the canal is slated to carry is 36 cubic metres per second, an amount that will make it possible to complete the irrigation of the entire Payuelos zone and transfer the necessary amounts of water to address the supplementary water needs of the irrigable zones of the Cea, Valderaduey and Carrión rivers.