Daily Water Watch: Carraízo Steady at 39.09 Meters

Day 28 of the metro rotation plan — interruptions paused since September 2, plan still in force. This morning’s 5:00 chart from the Autoridad de Acueductos y Alcantarillados shows Carraízo at 39.09 meters — down 2 centimeters from yesterday, and La Plata at 44.57 meters — down 2 centimeters from yesterday.

This is the 25th entry in our daily chart check (yesterday’s is here), built the same way every morning — from AAA’s own numbers, read off its charts for our reservoir board.

Carraízo: down 2 cm

Carraízo kept sliding. This morning’s chart puts it at 39.09 meters — down 2 centimeters from yesterday, in the observación band. The next line on the chart — into the ajustes band — sits at 38.50 meters, 0.59 meters below this morning’s reading. At AAA’s printed pace that is roughly 29.5 days out (straight-line date: 2026-10-04 — a projection, not a forecast; one wet afternoon moves it).

La Plata: down 2 cm

La Plata kept sliding. This morning’s chart puts it at 44.57 meters — down 2 centimeters from yesterday, in the ajustes band. The next line on the chart — into the control band — sits at 40.50 meters, 4.07 meters below this morning’s reading.

If your water comes from La Plata — Dorado, Guaynabo, Naranjito, Toa Alta, Toa Baja, Vega Alta, Bayamón, Cataño, Corozal — this is the reservoir to watch; AAA lists 130,828 client accounts on it.

What the numbers say

Carraízo has swung from a 4.3 cm-a-day decline last week to a 32.5 cm-a-day average rise this week, almost entirely thanks to one storm: 2.65 inches of rain fell on nearby gauges, with 1.14 inches on September 1 alone producing a 172 cm jump the next morning. That single spike is doing the heavy lifting — the smaller 0.78 inches on August 30 only nudged the level up 7 cm. Sitting at 39.09 m in the observación band, 0.59 m above the ajustes line below it, Carraízo is now arithmetically 2 days from crossing into the seguridad band above, around September 6, if this week’s pace held. Cidra shows a milder version of the same reversal, turning a 1 cm-a-day drop into a 2.2 cm-a-day rise after 6.31 inches of rain, putting it arithmetically 3 days from the observación line above, around September 7.

La Plata tells a different story: still falling, but the decline has eased from 8.2 to 4.3 cm a day even with less rain, 2.06 inches, than the other two reservoirs saw. It remains 4.07 m above the control line, and at this week’s slower pace that line is arithmetically 95 days out, around December 8. That’s a projection built purely on the current rate, not a forecast, and any further slowing would push it out further still.

What to watch

• Carraízo: whether the rise survives a dry week — this week’s gain came with 2.65 in of rain nearby.
• La Plata: whether the slowdown holds — a second week under 8.2 cm a day would say the rotation is doing its job.
• Cidra: whether the rise survives a dry week — this week’s gain came with 6.31 in of rain nearby.

The other rationing reservoir

Numbers from AAA’s Monitoreo Diario chart of 2026-09-04, read each morning for our reservoir board — where the levels, the bands, and the live rain gauges update daily. Rain figures are USGS gauges within 12 km of each reservoir (a proximity proxy, not a basin measurement). Day counts start 2026-08-08, when the metro rotation took effect. Straight-line dates are arithmetic, not forecasts. The analysis paragraphs are drafted by Claude from the computed figures and checked number-by-number against them before publishing.