Petaluma River

Petaluma River
The river flowing through Petaluma. View is to the southeast.
Petaluma River watershed (Interactive map)
EtymologyCoast Miwok
Location
CountryUnited States
StateCalifornia
RegionSonoma and Marin counties
CityPetaluma, California
Physical characteristics
Source 
  location1.5 mi (2 km) southwest of Cotati, California
  coordinates38°18′18″N 122°43′3″W / 38.30500°N 122.71750°W / 38.30500; -122.71750
  elevation332 ft (101 m)
MouthSan Pablo Bay
  location
5 mi (8 km) east of Novato, California
  coordinates
38°6′38″N 122°29′15″W / 38.11056°N 122.48750°W / 38.11056; -122.48750
  elevation
0 ft (0 m)
Length18 mi (29 km)
Basin size370 km² (140 sq. miles)
Discharge 
  locationPetaluma (USGS gage station 11459000)
  average17 cu ft/s (0.48 m3/s)
  minimum0 cu ft/s (0 m3/s)
  maximum9,620 cu ft/s (272 m3/s)
Basin features
Tributaries 
  leftLichau Creek, Lynch Creek, Washington Creek, Adobe Creek
  rightSan Antonio Creek

The Petaluma River is a river in the California counties of Sonoma and Marin that becomes a tidal slough for most of its length. The headwaters are in the area southwest of Cotati. The flow is generally southward through Petaluma's old town, where the waterway becomes navigable, and then flows another 10 mi (16 km) through tidal marshes before emptying into the northwest corner of San Pablo Bay.