Summary
Total streamflow across the
Mattole River
was last observed at
378
cfs, and is expected to yield approximately
750
acre-ft of water today; about 39%
of normal.
River levels are low and may signify a drought.
Average streamflow for this time of year is
965 cfs,
with recent peaks last observed
on
2023-03-14 when daily discharge volume was observed at
38,900 cfs.
Maximum discharge along the river is currently at the
Mattole R Nr Petrolia Ca
reporting a streamflow rate of 323 cfs.
This is also the highest stage along the Mattole River, with a gauge stage of
12.28 ft at this location.
This river is monitored from 2 different streamgauging stations along the Mattole River, the highest being situated at an altitude of 599 ft, the
Mattole R Nr Ettersburg Ca.
River Details
| Last Updated | 2025-12-04 |
| Discharge Volume | 750 ACRE-FT |
| Streamflow |
378.1 cfs
-19.1 cfs (-4.81%) |
| Percent of Normal | 39.18% |
| Maximum |
38,900.0 cfs
2023-03-14 |
| Seasonal Avg | cfs |
River Streamflow Levels
| Streamgauge | Streamflow | Gauge Stage | 24hr Change (%) | % Normal | Minimum (cfs) | Maximum (cfs) | Air Temp | Elevation |
|---|---|---|---|---|---|---|---|---|
|
Mattole R Nr Ettersburg Ca
USGS 11468900 |
55 cfs | 9.45 ft | -8.47 | |||||
|
Mattole R Nr Petrolia Ca
USGS 11469000 |
323 cfs | 12.28 ft | -4.15 |
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile
Historically, the Mattole Valley was home to the indigenous Mattole people who lived along the river for thousands of years. The river is unique in that it is one of the few undammed rivers left in California, allowing for a relatively natural flow regime. The Mattole River watershed provides critical habitat for threatened and endangered species, including coho and Chinook salmon, steelhead trout, and the Pacific lamprey. There are no major reservoirs or dams on the river, and the water is primarily used for agriculture and recreational purposes such as fishing, swimming, and river rafting.