Island No. 1

Island No. 1

Island No. 1, submerged in March 2023 (as seen from the northern part of an internal levee, looking south).
Island No. 1 Show map of San Francisco Bay Area Island No. 1 Show map of California Island No. 1 Show map of the United States
Geography
Location	Northern California
Coordinates	38°08′35″N122°20′40″W / 38.14306°N 122.34444°W / 38.14306; -122.34444 (Island No. 1) [1]
Adjacent to	Napa River
Highest elevation	3 ft (0.9 m) [1]
Administration
United States
State	California
County	Napa and Solano

Island No. 1 as it appears on a 1951 USGS topographic map.

USGS aerial imagery of Island No. 1 in 2021.

An aerial view, looking toward the west, of the Napa River where it flows into San Pablo Bay through Vallejo. Islands visible include, from bottom of image: Mare, No. 1, Knight, Russ, No. 2, Green, Bull, Edgerly, Coon, Little, and Tubbs.

Island No. 1 (formerly called Cross Island) ^[2] is a partially submerged island in the Napa River, upstream of San Pablo Bay (an embayment of San Francisco Bay). ^{[3] [4] [2]} It is in Napa and Solano County, California, and parts of it are managed as part of the Napa-Sonoma Marshes Wildlife Area. ^{[5] [6]} Its coordinates are 38°08′35″N122°20′40″W / 38.14306°N 122.34444°W / 38.14306; -122.34444 (Island No. 1) ^[1] , and the United States Geological Survey measured its elevation as 3 ft (0.91 m) in 1981. ^[1] It, along with Island No. 2, Green Island and Tubbs Island, are labeled on a 1902 USGS map of the area. ^[7]

References

1. U.S. Geological Survey Geographic Names Information System: Island No. 1
2. "Vallejo Proposes New Road To Bay Via San Rafael". The Sacramento Bee. Sacramento, California. May 18, 1921. p. 20.
3. California State Automobile Association (1999). San Francisco Bay Region (Map). 1:190,000. American Automobile Association.
4. "Salt plant will involve expenditure of $3,500,000". The Napa Valley Register. Napa, California. May 14, 1952. p. 16.
5. "Directional Map Napa-Sonoma Marshes Wildlife Area". California Department of Fish and Wildlife, Bay Delta Region. May 2019. Archived from the original on April 23, 2020. Retrieved February 26, 2021.
6. URS Corporation (May 2019). "Napa-Sonoma Marshes Wildlife Area Land Management Plan". California Department of Fish and Game. Retrieved February 26, 2021.
7. Goode, R.U.; Fletcher, L.C. (1902), Topography, State of California: Woodward Island Quadrangle, United States Geological Survey