USGS Streamgage 06485500
Big Sioux River at Akron, IA
Big Sioux River at Akron, IA is USGS streamgage 06485500 in Iowa, monitoring river discharge in hydrologic subbasin 10170203. It sits on the Big Sioux River, alongside 16 other gauges Rivermatics tracks on the same river. It drains a watershed of about 7,879 square miles. Discharge records at this site go back to 1928. Typical flow runs near 909.8 cfs in July and 1,448 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.
View live conditions & forecast →
Gauge details
- State
- Iowa
- Drainage area
- 7,879 sq mi
- Gauge elevation
- 1,125 ft
- Subbasin (HUC-8)
- 10170203
- Coordinates
- 42.83751, -96.56193
- USGS site number
- 06485500
- Records begin
- 1928-10-01 (98 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Big Sioux River at Akron, IA. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.
| Date | Low p10 | Expected p50 | High p90 | Range |
|---|---|---|---|---|
| 709 | 873 | 1,112 | ||
| 632 | 843 | 1,205 | ||
| 570 | 787 | 1,164 | ||
| 529 | 741 | 1,146 | ||
| 483 | 709 | 1,171 | ||
| 473 | 699 | 1,216 | ||
| 537 | 881 | 1,925 | ||
| 556 | 1,137 | 3,059 | ||
| 578 | 1,281 | 3,476 | ||
| 578 | 1,237 | 3,189 | ||
| 552 | 1,124 | 2,761 | ||
| 515 | 1,019 | 2,445 | ||
| 500 | 966 | 2,183 | ||
| 494 | 925 | 1,941 |
All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 98 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.
| Month | Low p10 | Typical p50 | High p90 | Range |
|---|---|---|---|---|
| January | 41.4 | 149.8 | 843.1 | |
| February | 52.3 | 273.4 | 1,660.8 | |
| March | 199.5 | 1,315.4 | 6,681.3 | |
| April | 373.3 | 1,448 | 10,024.3 | |
| May | 290 | 1,317.7 | 6,038.1 | |
| June | 237.8 | 1,417.7 | 7,021.7 | |
| July | 154.5 | 909.8 | 4,104.5 | |
| August | 99 | 525.1 | 2,314.2 | |
| September | 81.6 | 395.6 | 1,852.7 | |
| October | 79.5 | 318 | 2,368.4 | |
| November | 85.5 | 305.3 | 1,904.7 | |
| December | 65.3 | 217.4 | 1,490.6 |
All values in cubic feet per second (cfs).
Common questions
- When does Big Sioux River at Akron, IA normally run highest?
- April, on the long-term record. The median daily flow that month is about 1,448 cfs, against 149.8 cfs in January, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Big Sioux River at Akron, IA?
- It depends on the month. In January, half of days historically fall near 149.8 cfs, with the middle 80% of days between 41.4 and 843.1 cfs. The month-by-month table on this page gives the full range.
- How long has Big Sioux River at Akron, IA been measured?
- Discharge records at USGS site 06485500 begin in 1928, about 98 years, covering roughly 9,091 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Big Sioux River at Akron, IA?
- Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
- Where is Big Sioux River at Akron, IA?
- The gauge sits at 42.83751, -96.56193, in Iowa, in hydrologic subbasin 10170203, at an elevation of about 1,125 feet, draining roughly 7,879 square miles.
- Can I use Big Sioux River at Akron, IA data for flood or safety decisions?
- No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.
Upstream and downstream on the Big Sioux River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Big Sioux River in full.
- Big Sioux River near Florence, SD 68 sq mi
- Big Sioux River near Watertown, SD 525 sq mi
- Big Sioux River at Lake Kampeska near Watertown, SD 539 sq mi
- Big Sioux River at Watertown, SD 806 sq mi
- Big Sioux River at Broadway at Watertown, SD 870 sq mi
- Big Sioux River below Watertown, SD 1,000 sq mi
- Big Sioux River near Castlewood, SD 1,096 sq mi
- Big Sioux River near Bruce, SD 2,396 sq mi
- Big Sioux River near Brookings, SD 3,338 sq mi
- Big Sioux River near Dell Rapids, SD 3,927 sq mi
- Big Sioux River below Diversion at Sioux Falls, SD 3,999 sq mi
- Big Sioux River at Sioux Falls, SD 4,642 sq mi
- Big Sioux River at North Cliff Ave at Sioux Falls, SD 4,662 sq mi
- Big Sioux River near Hawarden, IA 7,566 sq mi
- Big Sioux River at Akron, IA this page
- Big Sioux River near Jefferson, SD 8,400 sq mi
- Big Sioux River at Sioux City, IA 8,430 sq mi