Location: Northwest Irrigation and Soils Research
Project Number: 2054-13000-010-002-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 1, 2020
End Date: Sep 30, 2023
Objective:
Evaluate the effects of conservation practices in the USR watershed in southern Idaho.
Approach:
Water samples will continue to be collected weekly during the irrigation season and biweekly during the winter from 10 sites (8 return flow and 2 inflow sites) in the Twin Falls irrigation tract to measure changes in sediment and nutrient losses from the watershed. Sediment and nutrient losses will be measured from a 200 ha subwatershed where fields have been converted from furrow irrigation to sprinkler irrigation over time. Legacy phosphorus contributions from irrigation laterals and return flow streams will be investigated. Bed sediment samples will be collected and analyzed for phosphorus concentrations including equilibrium phosphorus sorption concentration and sorption capacity. Advanced pattern recognition and machine learning processes will be used on publicly available remote sensing data to identify and map irrigation systems used on agricultural fields across the watershed. With this new methodology, changes in irrigation systems can be mapped and related to water quality dynamics in irrigation return flow streams.
