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The Delta

Table of Contents

• Recreation in the Delta
  The 1996 Delta Boating and Fishing Surveys Boater and Angler Characteristics and Activities Boater and Angler Recreation in the Delta
  • Table 1: Delta Statistics
  • Table 2: Delta Recreators' Origins & Activites
  • Figure 3: Delta Recreation
  • Table 3: Boating &Fishing Surveys of Delta Recreation*
• The Economy of the Delta Region
  • Table 4: Delta Economy Compared With California, 1994*
  • Table 5: Interindustry Transactions in the Delta Economy, 1994 (millions of dollars)
• Recreation Expenditures
  • Table 6: Estimated Recreational Expenditurues from Surveys*
• The Input-Output Model
• Economic Impacts of Recreational Boating and Fishing in the Delta
  • Table 7: Impacts of Boating & Fishing Activities in the Sacramento-San Joaquin Delta, 1995*

Submitted August 1998

Printed November 1998

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The Delta

The Sacramento-San Joaquin Delta is an important natural resource, providing a unique habitat for wildlife, prime agricultural land, opportunities for recreational activities, and the source of water for two-thirds of California's population. Located south of Sacramento and east of the San Francisco Bay, the Delta has historically received 47 percent of the State's runoff, flowing through the Sacramento, San Joaquin, Mokelumne, Cosumnes, and Calaveras rivers. The map in Figure 1 shows the Delta's drainage area, stretching from the northern border with Oregon, to the mountains bordering the southern edges of the Central Valley.

The Delta is a flat, low-lying region of rich mineral and peat soils. Originally lush wetland surrounded by riparian woodlands, the development of the Delta to its present form began in the late 1850's with the Swamp and Overflow Land Act. This act transferred ownership of all swamp and overflow land from the federal government to the State of California. The State sold these lands, using the proceeds to fund reclamation of the swamplands. The marshes were diked and drained, creating islands for agricultural development. Today, the levees provide multiple purposes including protecting the islands from flooding, defining the channels used for commercial and recreational navigation, contributing to regional flood control, protecting upland habitat areas on the islands, and protecting Delta water quality through reduced saltwater intrusion.

The Delta was given a legal boundary in 1959 with the passage of the Delta Protection Act (Section 12220 of the Water Code). Figure 2 shows the boundaries of the legal Delta, which include the shaded primary and secondary zones.

Table 1 provides some essential information about the Delta. In 1990 the Delta area, including parts of Alameda, Contra Costa, Sacramento, San Joaquin, Solano and Yolo counties, supported a population of 410,000. The Delta extends over 738,000 acres, of which 538,000 acres are presently used for agriculture, and 64,000 acres support cities and towns.

Waterways interlace the entire area, while 1,100 miles of levees protect the islands from flooding. The Pacific Flyway passes directly over the Delta, and some of the smaller unimproved islands provide suitable habitat for birds and other wildlife. These include 230 species of birds, 45 species of mammals, 52 species of fish, 25 species of reptiles and amphibians, and 150 species of flowering plants.

Figure 1: The Drainage Basin for the Delta and the
Major Water Conveyance Systems