A Short History of the Delta (part 1)

A lot of folks ask about the history of the California Delta.  Here is a chapter I will share with you out of a book I am writing about the Delta.   I will post it in a few parts.


A Short History of the California Delta (Part 1)

The Sacramento / San Joaquin Delta is the largest tidal estuary on the West Coast of the United States.  Technically it is an inverse delta where many waterways combine into one and empty into the sea.  This is the opposite of a delta such as the Mississippi where one or a few waterways expand into many as they reach the sea.  The Colorado River Delta was once much larger but it was destroyed by water diversions early in the 20th century.


About 140 million years ago the predecessors to the Sierras rose and eroded away giving rise to the present Sierra range.  Later perhaps 1,000,000 years ago the ice ages carved the Markley Gorge, which today lies about 2,000 to 5,000 feet under the floor of the Great Valley (the combined Sacramento and San Joaquin valleys collectively are known as the Great Valley).  As the sediment filled Markley Gorge the current Delta as we know it was created.  As the last ice age receded 10,000 to 12,000 years ago humans wandered down from the northern latitudes and settled the land we know today as California.

Probably the first written reference to the name California was in 1510 in the book: Las Sergas de Esplandin published in Seville and written by Garci Ordonez de Montalvo.  This was a fantasy and spoke of a mythical island in the West Indies populated by Amazons ruled by Queen Califia.  The early Spaniards gave the name to the land lying West of Mexico, which we now know as Baja California.  Originally this was thought to be an island and later the Spanish gave the name to all the territory from Cabo San Lucas to Alaska.

Aboriginal Culture

Indians were the first inhabitants of the central California area. Radio Carbon dating of shell mounds near San Francisco Bay show that the area was inhabited at least 3,000 to 4,000 years ago.  There were 425 recorded shell mounds around the bay and up into Suisun Bay.  These mounds were composed largely of mussel shells but many artifacts and human remains from burials were also found.  Some of these mounds were up to 40 feet high..  The vast majority of the mounds have been destroyed to build parking lots and shopping centers throughout the bay area.  Shellmound Road in Emeryville was so named because of its proximity to a large mound. 

At the time the Spanish began exploring California it is estimated that there could have been as many as 250,000 Native Americans in what is now the state.  The Maidu and Miwok groups inhabited the Delta  and its tributary river areas.  In the late 1700’s it is estimated that there were about 9,000 Maidu and about 11,000 Miwoks inhabiting about 1000 square miles of the greater Delta area in the Sacramento and San Joaquin Valleys.

The native cultures in the Delta and bay area used acorns as a dietary staple.  The acorns were gathered, stored and dried, and ground into meal and the acid leached out with water.  There was also a huge abundance of game and fish in the Delta area.  There were many villages in the Delta area and these lent their names to many local features.

These people lived in a Stone Age culture until the Spanish began settling the area with their missions in 1770.   After the missions were established most of the Indians that lived in proximity were either conscripted for labor or fled, many into the Delta area.  A terrible fever probably malaria swept through the Indian population starting in 1833.  Trappers passing through the Sacramento valley in the fall of 1832 reported a large Indian population but when they returned in the summer of 1833 they found only five living Indians between the head of Sacramento valley and the Kings River.  Malaria was probably brought to California by early adventurers, fur traders, and Spanish missionaries beginning in the early 1800′s, and remained epidemic in the Central Valley until the late 1800′s. By 1900 the level of malaria had been greatly reduced by the efforts of many of California’s mosquito control districts.


(To Be Continued)

All rights reserved, copyright California Delta Events / Bill Wells



About Bill Wells - A retired yacht broker, Bill is currently the Executive Director of the California Delta Chambers & Visitor's Bureau. He is an active member of the Northern California Fleet of the Classic Yacht Association. In their spare time he and his beloved wife Sue cruise their 1937 Stephens cruiser Ranger to boating events throughout the Delta. Bill is active in matters helping to preserve and protect the California Delta. He chronicles his adventures in the monthly Delta Rat Scrapbook column for Bay & Delta Yachtsman magazine.

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