Arroyo del Valle

Arroyo del Valle is a westward-flowing stream in Alameda County and Santa Clara County, California, USA, that is tributary to Arroyo de la Laguna which in turn flows into Alameda Creek. The stream drains much of the southern portion of the city of Livermore, and it also flows through and drains a considerable fraction of the city of Pleasanton. Water quality measurements in this stream indicate a pH level of 7.0, or neutral with respect to acidity; phosphate levels were not detectable. [ [http://www.pleasanton.k12.ca.us/amador/creek/projects/Bio99/JJM/exp.html Water Quality Testing in Arroyo del Valle] ] In previous times the Arroyo del Valle had a significant steelhead migration; however, degradation of the stream in the latter half of the 20th century has decimated this anadromous fish population. [ [http://www.pleasanton.k12.ca.us/AMADOR/Creek/history/index.html Arroyo del Valle Creekwatch] ]

In the middle reaches of Arroyo del Valle south of Livermore, there has been considerable historic grazing use. Depth to groundwater in this reach of the watershed typically ranges from convert|50|ft|m|0|lk=on to convert|100|ft|m|0 and flows to the west. ["Environmental Site Assessment, Murdell Lane, Unincorporated Alameda County", EMI Report 10202, September 29, 1989] Subsequent to this reach, the Arroyo del Valle flows down the moderately sloping hills to enter gravel pits, where extraction (but not processing) has historically been conducted by Lone Star Industries.

The total length of the stream is convert|33|mi|km.gnis|255060|Arroyo Valle]

ee also

*Arroyo de la Laguna
*Arroyo Mocho
*Mocho Subbasin
*Tesla Fault

References

ee also

*List of watercourses in the San Francisco Bay Area