Tropical Storm Lorena, the remnants.

Summary

September 10–11, 2025. The remnants of Tropical Storm Lorena, downgraded from a Category 1 hurricane that made landfall at Cabo San Lucas on September 9, advected northward across the Gulf of California and into southeastern Arizona. NWS Tucson issued a flood watch starting 18:00 MST on September 10 and a flood warning at 04:30 MST on September 11. The El Encanto cooperator gauge recorded 2.31″ between 03:14 and 17:08 MST — within 0.15″ of the previous September daily-rainfall record at that station (set in 2014).

This is the storm class for which our basin sizing rule (1-inch design event with a flow-through return to the gutter) is genuinely tested. Roughly half of the right-of-way basins on our active roll overflowed to the gutter at some point during the night; all returned within design parameters; none caused damage to adjacent property.

Gauges

Field notes

Marisol's phone went off at 04:18 MST when the first downstream homeowner called to report the curb-cut basin "overflowing in a good way" — meaning the basin's flow-through return was discharging visibly to the gutter, exactly as designed. By 06:00, six homeowners had texted variations of the same observation. By 09:00, two had reported sediment buildup at curb cuts that needed clearing.

The crew met at Bay 3 at 07:30 and split into two teams. Marisol and Daniel drove the central neighborhoods (El Encanto, Sam Hughes, Reid Park) checking ten of our highest-volume basins. Antón and Ben drove the Catalina Foothills, where rainfall had been higher. June stayed at the shop and worked the dashboards: every cistern with a Levelogger reported full or near-full state, and every controller had logged an irrigation skip overnight (the rain switches did their job).

By 14:00 we had cleared sediment at four right-of-way basins and one driveway-side basin. Total crew time: 11 person-hours. All work absorbed under our 30-day callback warranty for the storms; no client was billed.

What we found in the morning

• Cisterns. All 94 active cisterns reached overflow at some point during the storm. None failed. The biggest issue was at the Catalina Foothills CF-002 array, where the flow rate from one of the linked tanks slightly exceeded the manifold's design and produced a visible 1-inch back-up in the second tank for about 40 minutes — within tolerance, but worth noting.
• Basins. Of 142 active sites, 71 had visible water in their basins for more than 12 hours after the storm ended. Of those 71, 9 had basin sediment that needed to be cleared from curb cuts.
• Greywater. Branched-drain systems on flat lots performed normally; no surge issues. One greywater outlet on a sloped lot had a slug of mulch wash up against it; cleared.
• AC condensate. All AC systems shut off during the cool overnight period; no condensate produced.