Status: Active
Funding Status: Funded
Dates: 04/11/2015 - 12/31/2100

The Spence Vegetated Treatment System (VTS) mitigates irrigation run-off from vegetable and strawberry fields at the USDA Spence site south of Salinas, CA. The main features of the VTS include an existing 1800-ft long ditch, vegetated with native grass (festuca rubra) that drains 86 acres of vegetables and strawberries. The dense grass vegetation can slow the flow of run-off during the irrigation season, and settle out fine sediment and associated nutrients, as well as uptake soluble nutrients (nitrate and orthophosphate). In addition, the grasses can reduce the volume of run-off by increasing infiltration and evapotranspiration losses. Fescue has small seeds and will not represent habitat for birds or rodents, therefor alleviating food safety concerns. Run-off draining to the lowest end of the VTS will be collected in a sump and reapplied to the sides of the ditch using drip tape. Water applied to the sides of the ditch will maintain the grass through the dry season and will increase the treatment surface area. During heavy storm events the vegetation will prevent the erosion of the sides of the ditches. We plan to install sediment traps at points where run-off enters the VTS from agricultural fields to settle out large-sized particles.

Goals

1) Remove nutrients from irrigation runoff, 2) Be a demonstration site for agriculture (growers, researchers and professionals) interested in nutrient mitigation,

Programs

• Agriculture
• Irrigation Nutrient Management
• Water Quality

Funders

• State Water Resources Control Board

Contact

Pam Krone-Davis
831-647-4238
pam.krone-davis@noaa.gov

Photos & Images