USGS Streamgage 06101500
Marias River near Chester, MT
Marias River near Chester, MT is USGS streamgage 06101500 in Montana, monitoring river discharge in hydrologic subbasin 10030203. It drains a watershed of about 4,944 square miles. Discharge records at this site go back to 1921. Typical flow runs near 792.7 cfs in July and 524.2 cfs in April, with the higher of the two arriving in July.
Gauge details
- State
- Montana
- Drainage area
- 4,944 sq mi
- Gauge elevation
- 2,823 ft
- Subbasin (HUC-8)
- 10030203
- Coordinates
- 48.30596, -111.08053
- USGS site number
- 06101500
- Records begin
- 1921-04-01 (105 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 105 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 | 184.2 | 453.5 | 691.7 | |
| February | 189.2 | 489.1 | 804.3 | |
| March | 219.2 | 494.5 | 1,138.5 | |
| April | 275.6 | 524.2 | 1,453.7 | |
| May | 396.7 | 789.3 | 2,272.3 | |
| June | 440.5 | 1,055.9 | 3,119.7 | |
| July | 381.4 | 792.7 | 2,258.4 | |
| August | 270.4 | 671.5 | 1,543.2 | |
| September | 323.1 | 631.4 | 1,426.3 | |
| October | 279.2 | 553 | 1,201.3 | |
| November | 249.2 | 510.8 | 1,015.1 | |
| December | 200.2 | 490.8 | 696.9 |
All values in cubic feet per second (cfs).