Daily Water Watch: Carraízo at 38.83 Meters

Day 32 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 38.83 meters — down 4 centimeters from yesterday, and La Plata at 44.40 meters — down 6 centimeters from yesterday.

This is the 29th 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 4 cm

Carraízo kept sliding. This morning’s chart puts it at 38.83 meters — down 4 centimeters from yesterday, in the observación band. The next line on the chart — into the ajustes band — sits at 38.50 meters, 0.33 meters below this morning’s reading. At AAA’s printed pace that is roughly 8.3 days out (straight-line date: 2026-09-17 — a projection, not a forecast; one wet afternoon moves it).

La Plata: down 6 cm

La Plata kept sliding. This morning’s chart puts it at 44.40 meters — down 6 centimeters from yesterday, in the ajustes band. The next line on the chart — into the control band — sits at 40.50 meters, 3.90 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 continues its slow slide, down 1.5 cm a day this week, essentially matching last week’s 1.7 cm-a-day pace — the decline hasn’t accelerated, just persisted, with five straight lower mornings totaling -28 cm. The 0.95 in of rain on September 7 didn’t help; the next morning’s reading still fell 4 cm. The reservoir sits 0.33 m above the ajustes line, and at the current rate that line is roughly 22 days out, around September 30 — arithmetic, not a forecast. La Plata’s decline, by contrast, is easing meaningfully, from 9.3 cm a day down to 3.2 cm a day, though it too logged five straight lower mornings for -19 cm. With 3.90 m of cushion above the control line, the pace works out to about 122 days before that line would be reached.

Cidra remains essentially flat, off just 0.2 cm a day, within chart-reading noise, and sitting 1.79 m above its control line with no meaningful streak either way. Rain this week was heaviest on September 7 across all three watersheds, but only Cidra held steady the next morning, at 0 cm, while Carraízo dropped. That split suggests the rain was too light or too localized to meaningfully offset ongoing draw-down at Carraízo and La Plata, even as La Plata’s own trend keeps softening.

What to watch

• La Plata: whether the slowdown holds — a second week under 9.3 cm a day would say the rotation is doing its job.

The other rationing reservoir

Numbers from AAA’s Monitoreo Diario chart of 2026-09-08, 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.