Provisional Monthly Streamflow Network - Tabular Data: September 2024
Choose another month| Long-term monthly flows for period of record (cfs) | ||||||||
| Station | Drainage area (sq. mi.) | Years of record | Monthly mean flow (cfs) | Mean flow* | Median (50% exceedence) flow | 90% exceedence flow | 10% exceedence flow | USGS Station No. | 
| Rock River at Rockton | 6,363 | 85 | 4,154 | 3,339 | 2,787 | 1,166 | 7,026 | |
| Rock River near Joslin | 9,549 | 85 | 6,028 | 4,878 | 4,054 | 1,784 | 9,387 | |
| Pecatonica River at Freeport | 1,326 | 110 | 1,000 | 835 | 669 | 313 | 1,539 | |
| Green River near Geneseo | 1,003 | 89 | 172 | 374 | 183 | 61 | 1,048 | |
| Edwards River near New Boston | 445 | 90 | 28 | 141 | 53 | 16 | 389 | |
| Kankakee River at Momence | 2,294 | 111 | 680 | 1,086 | 830 | 553 | 1,945 | |
| Iroquois River near Chebanse | 2,091 | 102 | 117 | 591 | 130 | 45 | 1,814 | |
| Fox River at Dayton | 2,642 | 110 | 859 | 1,118 | 746 | 263 | 2,822 | |
| Vermilion River at Pontiac | 579 | 82 | 3 | 127 | 18 | 2 | 616 | |
| Spoon River at Seville | 1,636 | 111 | 154 | 587 | 203 | 59 | 1,380 | |
| LaMoine River at Ripley | 1,293 | 104 | 29 | 451 | 121 | 26 | 1,172 | |
| Bear Creek near Marcelline | 349 | 81 | 3 | 148 | 20 | 1 | 449 | |
| Mackinaw River near Congerville | 767 | 80 | 14 | 225 | 29 | 6 | 715 | |
| Salt Creek near Greenview | 1,804 | 83 | 165 | 463 | 227 | 122 | 987 | |
| Sangamon River at Monticello | 550 | 116 | 15 | 119 | 27 | 8 | 337 | |
| So. Fork Sangamon near Rochester | 867 | 76 | 13 | 178 | 23 | 3 | 456 | |
| Illinois River at Valley City | 26,743 | 86 | 5,624 | 12,141 | 8,227 | 6,295 | 24,920 | |
| Macoupin Creek near Kane | 868 | 97 | 37 | 205 | 48 | 8 | 498 | |
| Vermilion River near Danville | 1,290 | 104 | 188 | 296 | 113 | 47 | 873 | |
| Kaskaskia River at Vandalia | 1,940 | 55 | 116 | 560 | 367 | 61 | 2,387 | |
| Shoal Creek near Breese | 735 | 83 | 136 | 179 | 55 | 12 | 434 | |
| Embarras River at Ste. Marie | 1,516 | 113 | 112 | 351 | 118 | 37 | 1,055 | |
| Skillet Fork at Wayne City | 464 | 108 | 87 | 85 | 18 | 1 | 229 | |
| Little Wabash below Clay City | 1,131 | 111 | 55 | 234 | 63 | 8 | 826 | |
| Big Muddy at Plumfield | 794 | 54 | 359 | 185 | 106 | 49 | 418 | |
| Cache River at Forman | 244 | 101 | 87 | 55 | 13 | 2 | 183 | |
| Choose another month Station Numbers are linked to the U.S. Geological Survey, providing more information about each station. Notes: Much below normal flow = 90-100% chance of exceedence. Below normal flow = 70-90% chance of exceedence. Normal flow = 30-70% chance of exceedence. Above normal flow = 10-30% chance of exceedence. Much above normal flow = 0-10% chance of exceedence. * As reported in U.S. Geological Survey (USGS) Water Resources Data, Illinois, Water Year 2022. For best results when printing this page, change your layout to "Landscape". Streamflow Data | 


