El Encanto monsoon burst.

Summary

July 17, 2025. National Weather Service Tucson issued a flood advisory for the Tucson metro at 15:42 MST. The cell tracked west-to-east across central Tucson between 16:08 and 16:49, producing 1.84″ of rainfall at the El Encanto cooperator gauge — the strongest monsoon-onset burst at that station since 2018. Tucson International (KTUS) recorded only 1.62″ over a slightly longer window because the cell weakened crossing the airport. Davis-Monthan (KDMA) recorded 0.92″.

The storm produced significant urban flooding along Speedway between Tucson Boulevard and Country Club, where the City of Tucson RainTalk network shows individual gauges reading between 1.3″ and 2.1″ within a half-mile radius — typical of monsoon cell variability.

Gauges

Field notes

Crew: Antón Quezada on a regrade in El Encanto, eight blocks east of the cooperator gauge. Marisol Reyes on a cistern install in Sam Hughes, four blocks east. Both noted the dramatic light shift at 16:00 — sun gone behind a cloudbank, ambient temperature drop from 99°F to 79°F in twelve minutes per Antón's truck thermometer.

Antón pulled the crew out of the trench at 15:55 when the wind shifted, which turned out to be correct: the cell hit the El Encanto site at 16:08 and the half-finished swale he was on filled to within an inch of grade in 22 minutes. Marisol, four blocks east, reports the El Encanto neighborhood streets running curb-to-curb by 16:30 with significant sediment carry. Both crew members watched the previously installed basin at SH-001 intercept its share of street water successfully — the curb cut took the full inflow, the basin filled to about 80% of its volume, and the surface water cleared from the basin within roughly four hours.

What it captured

Across our 142 active sites, the storm event delivered an estimated 31,400 gallons of new capture between cisterns and basins. Specific outcomes by property type:

• Sam Hughes / Sam Hughes-equivalent (0.18 ac, 2,600 sf roof): Cistern filled from ~30% to overflow on the long elevation; right-of-way basin received roughly 600 gallons via the curb cut. Total capture estimated at 2,200 gallons.
• Catalina Foothills (0.6 ac, 4,000+ sf roof): Cistern array intercepted approximately 4,800 gallons; the rest overflowed to basins on the slope.
• Smaller Barrio lots (0.10 ac, <1,800 sf): Basin-and-cistern captures of 800–1,400 gallons.

The storm tested every basin and cistern we'd installed since 2018 in the El Encanto / Sam Hughes / Reid Park area. We had two service callbacks in the following 72 hours, both for basin sediment buildup at curb cuts. Both were resolved in under two hours of crew time at no charge under our 30-day callback warranty.