Reclamation District No. 1000 was created by an act of the State Legislature on April 8, 1911. The purpose was to allow for the reclamation of what was then known as the American Basin for agricultural purposes. The American Basin historically flooded from the Sacramento and American Rivers overflowing their banks due to winter rains and runoff from the foothills giving it the rich fertile soil to support the agriculture which dominated the early years in Natomas. Much of the land was owned by the Natomas Company of California The Act gave the District authority and responsibility for flood control and drainage in what has become the Natomas Basin.
Reclamation of Natomas began in 1913 with construction of the perimeter levee system which was completed in 1915. The original cost was approximately $2 million and was financed by the sale of bonds. Some of these original bonds are still in the possession of the District. Following completion of the levees, an interior drainage system consisting canals, ditches and drains was constructed to collect both stormwater runoff from precipitation that falls within the leveed area as well as agricultural runoff from irrigated farm land. The original system conveyed all the runoff to a large pumping plant constructed in 1915 at the terminus of Second Bannon Slough (Plant 1A). This plant still exists and is used today. It is located directly across the Garden Highway from the District Office. A second pumping plant (Plant 2) was added at Pritchard Lake in 1920 along the Sacramento River north of Elvertal Road, and a third plant (Plant 3) was added in 1939 also located on the Sacramento River just north of San Juan Road. Eventually five more pump plants were added at various locations in the District to accommodate more development and relieve pressure on the original plants.