COLUMBIA--BLO ROCK ISLAND DAM (RISW1)
| Observed | Forecast/Trend Issued: 2026-05-11 10:45 PDT | ||
| Date/Time (PDT) | Pool Height | Date/Time (PDT) | Pool Height |
| 2026-05-11 00:00 | 611.89 | 2026-05-11 17:00 | 611.49 |
| 2026-05-10 00:00 | 612.57 | 2026-05-11 23:00 | 611.49 |
| 2026-05-09 00:00 | 612.13 | 2026-05-12 05:00 | 611.49 |
| 2026-05-08 00:00 | 611.77 | 2026-05-12 11:00 | 611.49 |
| 2026-05-07 00:00 | 612.11 | 2026-05-12 17:00 | 611.49 |
| 2026-05-06 00:00 | 612.51 | 2026-05-12 23:00 | 611.49 |
| 2026-05-05 00:00 | 612.3 | 2026-05-13 05:00 | 611.49 |
| 2026-05-04 00:00 | 612.2 | 2026-05-13 11:00 | 611.49 |
| 2026-05-03 00:00 | 612.25 | 2026-05-13 17:00 | 611.49 |
| 2026-05-02 00:00 | 612.27 | 2026-05-13 23:00 | 611.49 |
| 2026-05-01 00:00 | 612.18 | 2026-05-14 05:00 | 611.49 |
| 2026-05-14 11:00 | 611.49 | ||
| 2026-05-14 17:00 | 611.49 | ||
| 2026-05-14 23:00 | 611.49 | ||
| 2026-05-15 05:00 | 611.49 | ||
| 2026-05-15 11:00 | 611.49 | ||
| 2026-05-15 17:00 | 611.49 | ||
| 2026-05-15 23:00 | 611.49 | ||
| 2026-05-16 05:00 | 611.49 | ||
| 2026-05-16 11:00 | 611.49 | ||
| 2026-05-16 17:00 | 611.49 | ||
| 2026-05-16 23:00 | 611.49 | ||
| 2026-05-17 05:00 | 611.49 | ||
| 2026-05-17 11:00 | 611.49 | ||
| 2026-05-17 17:00 | 611.49 | ||
| 2026-05-17 23:00 | 611.49 | ||
| 2026-05-18 05:00 | 611.49 | ||
| 2026-05-18 11:00 | 611.49 | ||
| 2026-05-18 17:00 | 611.49 | ||
| 2026-05-18 23:00 | 611.49 | ||
| 2026-05-19 05:00 | 611.49 | ||
| 2026-05-19 11:00 | 611.49 | ||
| 2026-05-19 17:00 | 611.49 | ||
| 2026-05-19 23:00 | 611.49 | ||
| 2026-05-20 05:00 | 611.49 | ||
| 2026-05-20 11:00 | 611.49 | ||
| 2026-05-20 17:00 | 611.49 | ||
| 2026-05-20 23:00 | 611.49 | ||
| 2026-05-21 05:00 | 611.49 | ||