Arroyo De La Laguna
From prehistoric times much of the eastern part of the Amador Valley consisted of a lake known as Tulare Lake. With development of the valley starting in the 19th century, drainage alterations in this watershed reduced the lake to a watercourse now called the Arroyo de la Laguna.
Hydrogeology
In the northern portion of the Arroyo de la Laguna catchment basin, the Tassajara Formation underlies Quaternary valley fill material. Contacts of these two formations are often indistinguishable due to similarities of physical characteristics. The prism of sediments identified as valley fill materials contains from eight to ten separate zones of sand and gravel separated by zones of silt and clay.
Rapid development and other historic changes in the upper watershed have caused severe instability in the lower 5 miles of the Arroyo de la Laguna.
See also
- List of watercourses in the San Francisco Bay Area
- Mocho Subbasin
- Pleasanton Fault
- Tassajara Formation