Estero Americano is an estuary 9.2 miles (15 km) long that drains into Bodega Bay and is fed by Americano Creek that flows west for 7.5-mile (12 km) from the coastal hills of Sonoma and Marin Counties, about 19 miles (31 km) southwest of Santa Rosa and 3.7 miles (6 km) northwest of Dillion Beach, California. Americano Creek is dry for 4 to 6 months each year. For its first 8 miles (13 km), the stream meanders through a broad valley dominated by agricultural uses, principally cattle grazing. The Estero Americano is protected by the Estero Americano State Marine Recreational Management Area, which protects marine life and helps conserve marine ecosystems.
Two Coast Miwok villages were historically located on the Estero Americano. Uli-yomi was at the head where the creek enters the estuary and Awachi was at the mouth on Bodega Bay. At the time of the Russian colony at Fort Ross from 1812 to 1841, Americano Creek was known as the Avacha River. At the direction of Governor José Figueroa in 1835, Mariano Guadalupe Vallejo began construction of the Presidio of Sonoma to counter the Russian presence at Fort Ross. To extend the settlements in the direction of Fort Ross, Vallejo sent three “Americano” settlers, Edward McIntosh, James Black, and James Dawson. Black settled upon what is now known as Rancho Cañada de Jonive, while Dawson and McIntosh settled upon Rancho Estero Americano and raised cattle.
Today, much of the Estero Americano is designated as an impaired stream due to runoff from pasture land and feedlots. In some years this condition is exacerbated when a sand bar forms at the mouth of the estuary that restricts tidal flushing, otherwise tidal circulation extends 4 miles (6.5 km) upstream. The estuary supports marshes and marine invertebrates that are critical for seabirds and fish habitat. Estero Americano State Marine Recreational Management Area is one of 22 marine protected areas adopted by the California Department of Fish and Game as part of the Marine Life Protection Act Initiative. This was a collaborative public process that included local divers, fishermen, conservationists, and scientists. They were tasked with designing a network of protected areas that would preserve sensitive sea life and habitats while enhancing recreation, study, and education opportunities. The north-central coast marine protected areas took effect in 2010. Read more here and here. Explore more of Estero Americano here: