This document presents an overview of the historical changes that have shaped the Santa Clara River and its surrounding environment. Three chronological areas are examined. First, the Agrarian Era (1782-1870s) documents the indigenous populations and the arrival of the Spanish and Mexican settlers and their interactions with the river. Second, the Commercial Era (1870-1920) describes the intensification of settlement and agriculture in the Santa Clara River valley and the rising competition for use of water. The final section, the Industrial Era (1920-present) desmonstrates the rise of conflicting interests, including agriculture, commerce, development and government.