In the same basin of the Duratón river, but outside its channel, between the towns of Aldeayuso and Langayo, is the dam and the Valdemudarra reservoir. It belongs to the Duero hydrographic basin and has an area of 33 hectares, and 5 cubic hectometres of capacity.

It is a water resource that supplies water to the community of irrigators in the nearby lands, with two water uses:

• one from the Duratón river, which derives water between the months of November and March
• another from the Duero River, without temporal limitation, which completes the supply of water that cannot be supplied from the Valdemudarra stream.

Being a water area, you can enjoy watching the birds (birding) that stop here to get water, especially migratory birds.