Agricultural

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Idaho

United Electric Cooperative/ Southwest Irrigation District Aquifer Recharge Project

BPA recently signed a one-season demonstration agreement with United Electric Cooperative to evaluate the ability of the Southwest Irrigation District system to increase pumping during light load hours. The project kicked-off in early March and will conclude in November.

UEC proposed the idea following a discussion between BPA and Northwest Requirements Utilities members regarding potential irrigation load solutions to oversupply challenges.

In 2010, Southwest Irrigation District installed a pumping system to recharge an aquifer located west of Burley on United Electric Co-op’s system. The system pumps water from the Snake River through three pipelines, to injection wells and/or irrigation canals. Aquifer recharge occurs in two ways – either through direct pumping into the aquifer or by using the irrigation canals to avoid withdrawing water from the aquifer. The installed capacity of the pumping system on United Electric’s system is approximately 1.8 MW.

Increasing loads during LLH has several potential benefits:

• Help address spring oversupply events
• Sustained increases in light load hour loads could help increase market prices
• Use expanding levels of renewable energy being produced in the region
• Create enhanced revenue opportunities for both BPA and customer utilities
• Test ability to dispatch irrigation pumping loads
• Evaluate impact (if any) of transfer scheduling, costs and/or process