San Antonio Creek (Marin County, California) facts for kids

San Antonio Creek is a river in California, United States. It flows north and then east. This creek marks part of the border between Marin and Sonoma counties. It eventually flows into the Petaluma River, where the water rises and falls with the ocean tides.

History of San Antonio Creek

Long ago, two Native American villages of the Coast Miwok people were built along San Antonio Creek. Their names were Meleya and Amayelle. These were permanent villages.

The creek was named by early Spanish explorers. They named it after Saint Anthony of Padua. He was a special saint for the Franciscan Order. The creek flows through an old land grant called Rancho Laguna de San Antonio. This land was given by Governor Pío Pico to Bartolomé Bojorquez in 1845.

Where the Creek Flows

San Antonio Creek starts high up on Antonio Mountain in Marin County. A long time ago, there was a small lake where the creek begins. This lake was drained between 1860 and 1885. This was done so the land could be used for farming.

From its start, the creek flows north for about 2 miles (3.2 km) into Chileno Valley. Then it turns east-southeast. At this point, it begins to form the county line. The creek flows under Chileno Valley Road and Point Reyes-Petaluma Road. It then runs next to San Antonio Road, heading east towards U.S. 101.

The creek crosses under U.S. 101. Around 1930, the creek was moved here. It was diverted to the Schultz Slough and the Petaluma River. This change was made about 5.2 miles (8.4 km) upstream from where it used to connect to the San Antonio Slough. This old connection was near Hog Island in the wetlands south of Petaluma, California. Moving the creek upstream made its flow slower. This caused dirt and sand to build up in the lower parts of the creek.

Animals in the Creek

San Antonio Creek used to have water flowing all year round, especially in its lower parts. Until the mid-1900s, steelhead trout were quite common here. Even though some steelhead were seen in 2000, they seem to have disappeared from the creek now.

Other fish like California roach and threespine stickleback are still found. These types of fish often live in the same places as steelhead.

A very large striped bass ((Morone saxatilis)) was caught in San Antonio Creek in 1912. Charles R. Bond caught this fish. It weighed 87 pounds, 8 ounces (39.7 kg) and was 5 feet, 9 inches (1.75 m) long. This was the biggest striped bass ever caught with a fishing rod and line at that time. A newspaper article from 1909 also mentioned Charles Bond catching a 55-pound (25 kg) striped bass in the "San Antone Slough."

Bridges Over the Creek

Several bridges cross San Antonio Creek. The bridges on U.S. 101 are each two lanes wide. They are about 120 feet (37 m) long. The northbound bridge was built in 1929 and fixed up in 1979. The southbound bridge was built in 1947.

There is also a bridge on San Antonio Road. It is about 0.6 miles (1.0 km) north of U.S. 101. This bridge was built in 1917. It is a concrete tee beam bridge, 101 feet (31 m) long.

Marshall Petaluma Road crosses the creek on a 25-foot (7.6 m) concrete tee beam bridge. This bridge was built in 1929. Point Reyes Petaluma Road crosses on a 102-foot (31 m) concrete slab bridge. This one was built in 1964.