Document Type

Capstone Project

Degree Name

Bachelor of Science (B.S.)


Science & Environmental Policy


The primary goal of the study is to determine typical sediment yields from irrigated agricultural fields in the Salinas Valley, California. The study present here quantified erosion amounts from vegetable row croplands by measuring water application, runoff and sediment loads coming from row crops in the Salinas Valley during irrigation and rainfall events. It estimated that for the period April 2000 through March 2001, 234 kilo-tonnes (2.9tonnes/ha) of soil eroded from approximately 60% of agricultural row-croplands. These lands had slopes less than 2.3%. It was estimated that 70% of this eroded material was of silt & clay composition. Finally, it was determined that a properly functioning and maintained detention basin could remove over 99% of sediment from water leaving the basin. The ultimate goal is to use these data in the larger scope of the Salinas River sediment budget to help establish the total maximum daily load (TMDL) for sediment in the river. This is related to two larger issues. First, it is in partial compliance with the Clean Water Act to address non-point source pollution. Second, it addresses concerns over habitat degradation of the steelhead trout (Onchorhynchus mykiss mykiss), protected under the Endangered Species Act.


Capstone Project (B.S.) Earth Systems Science & Policy Institute