Thank you Anirban,
this is the Guadalquivir river, the biggest in the Andalucía region. This part was separated from the main one -I think...- to prevent the quite often overflowing of the river in that part of the city known as "Triana" neighbourhood. Is now used for many water sports as you can see here.
The color was a chance with my vantage point, reflection, bottom and light angle...and some postproduction.