| Cuenca | Capacidad | Embalsada | Variacion | ||
| Tajo | 11009 | 8043 | (73.06%) | 23 | (0.21%) |
| Guadiana | 8630 | 7536 | (87.32%) | 87 | (1.01%) |
| Guadalquivir | 8287 | 7225 | (87.18%) | 291 | (3.51%) |
| Duero | 7493 | 6645 | (88.68%) | 24 | (0.32%) |
| Ebro | 7403 | 5654 | (76.37%) | -109 | (-1.47%) |
| Norte | 3663 | 3165 | (86.40%) | -111 | (-3.03%) |
| Júcar | 3345 | 1642 | (49.09%) | 56 | (1.67%) |
| C. Atl. Andaluza | 1878 | 1773 | (94.41%) | 26 | (1.38%) |
| C. Med. Andaluza | 1177 | 910 | (77.32%) | -6 | (-0.51%) |
| Segura | 1129 | 659 | (58.37%) | 28 | (2.48%) |
| Cataluña Interna | 740 | 497 | (67.16%) | 7 | (0.95%) |
| Galicia Costa | 684 | 550 | (80.41%) | -3 | (-0.44%) |
| Pais Vasco Interna | 21 | 20 | (95.24%) | 0 | (0.00%) |
