The City of Nampa will shut down its irrigation system for the season on Monday, September 28, marking the end of water delivery for residential and commercial properties in Canyon County. The shutdown date aligns with schedules set by the Pioneer Irrigation District, Nampa-Meridian Irrigation District, and Boise-Kuna Irrigation District, the three entities that supply water to the city.
Water Supply and District Coordination
Nampa relies on deliveries from all three districts to fully operate its pressurized irrigation network. Each district determines when to cut off service to customers as they approach the end of their annual allotments. The length of the irrigation season varies depending on water availability in the Treasure Valley.
Unlike municipal water, Nampa’s irrigation supply is not metered. Instead, yearly assessments are calculated based on the square footage of each property. This flat-rate structure means residents pay for access to the system rather than volume used, a model that has long served agricultural and residential users in the region.
Recycled Water Extends Season
During the summer months, Nampa added up to 12 million gallons of Class A recycled water daily to the Phyllis Canal. This volume represents approximately 15 percent of the city’s total irrigation needs. The use of recycled water is equivalent to preserving 5,000 acre-feet of storage in reservoirs that supply Nampa and surrounding areas.
By recycling water for irrigation, the city extends the length of the season by keeping more natural water in storage. Class A recycled water undergoes continuous testing and meets rigorous safety standards, ensuring it is safe for landscape use. For broader context on Idaho’s agricultural water challenges, see coverage at Idaho News.
Advice for Property Owners
The City of Nampa and the Irrigation Division have issued guidance for residents preparing for winter. Officials advise against using potable water to irrigate lawns, noting that it significantly increases utility bills. Additionally, homeowners are warned not to turn off the city valve when blowing out sprinkler lines, a practice that can damage infrastructure.
As harvest season progresses in Canyon County, drivers should also exercise caution around agricultural machinery on local roads. For more on traffic safety during this busy period, read ITD Urges Caution as Harvest Machinery Floods Canyon County Highways. With irrigation services ending, property owners must complete winterization tasks before the September 28 cutoff to avoid system damage.