Infrastructure

Daily Water Watch: Carraízo Back in the Observación Band

Published Sep 2, 2026 · 787 Daily · Original analysis

Day 26 of the metro rotation. This morning’s 5:00 chart from the Autoridad de Acueductos y Alcantarillados shows Carraízo at 38.92 meters — up 172 centimeters from yesterday, and La Plata flat at 44.59 meters.

This is the 23th 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: a rise

Carraízo gained ground overnight. The level crossed a band line: the chart now reads observación, up from ajustes yesterday. This morning’s chart puts it at 38.92 meters — up 172 centimeters from yesterday, in the observación band. The next line on the chart — into the ajustes band — sits at 38.50 meters, 0.42 meters below this morning’s reading.

ajustes line · 38.50 m 37.57 38.92 — today ▲
Carraízo since 2026-08-20 (meters above sea level), against the ajustes line. Data: AAA Monitoreo Diario.

Carraízo · September 2

Level today
38.92 mband: observación
Change since yesterday
+172 cm
To the ajustes line
0.42 mline at 38.50 m
At the current pace
rising

La Plata: holding

La Plata held its level. This morning’s chart puts it flat at 44.59 meters, in the ajustes band. The next line on the chart — into the control band — sits at 40.50 meters, 4.09 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.

control line · 40.50 m 45.55 44.59 — today
La Plata since 2026-08-20 (meters above sea level), against the control line. Data: AAA Monitoreo Diario.

La Plata · September 2

Level today
44.59 mband: ajustes
Change since yesterday
0 cm
To the control line
4.09 mline at 40.50 m
At the current pace
holding

What the numbers say

Over the past week Carraízo has been rising an average of 27.7 cm a day, a reversal from a 4.5 cm-a-day decline the week before. That is 3 straight mornings higher, +185 cm in all. Since the rotation began 24 days ago it has gained 139 cm, from 37.53 m. If this week’s rise held, the level would re-enter the band above (39.70 m) in about 3 days, around September 5. Nearby USGS gauges recorded 1.99 in of rain this week, most of it September 1 (1.14 in). After the 0.78 in on August 30, the next morning’s reading was +7 cm. After the 1.14 in on September 1, the next morning’s reading was +172 cm.

Over the past week La Plata has been falling an average of 7.5 cm a day, about the same pace as the week before (6.7 cm a day). Since the rotation began 24 days ago it has lost 179 cm, from 46.38 m. At this week’s pace the control line (40.50 m) is about 55 days away — around October 27; arithmetic, not a forecast. Nearby USGS gauges recorded 1.97 in of rain this week, most of it August 30 (1.45 in). After the 1.45 in on August 30, the next morning’s reading was -5 cm.

Over the past week Cidra has been rising an average of 1.7 cm a day, a reversal from a 0.8 cm-a-day decline the week before. That is 3 straight mornings higher, +15 cm in all. Since the rotation began 24 days ago it has gained 4 cm, from 400.13 m. If this week’s rise held, the level would re-enter the band above (400.23 m) in about 4 days, around September 6. Nearby USGS gauges recorded 6.14 in of rain this week, most of it September 1 (2.81 in). After the 1.84 in on August 30, the next morning’s reading was +4 cm. After the 1.3 in on August 31, the next morning’s reading was +7 cm.

What to watch

  • Carraízo: whether the rise survives a dry week — this week’s gain came with 1.99 in of rain nearby.
  • Cidra: whether the rise survives a dry week — this week’s gain came with 6.14 in of rain nearby.

The other rationing reservoir

Cidra · September 2

Level today
400.17 mband: ajustes
Change since yesterday
+4 cm
To the control line
1.80 mline at 398.37 m
At the current pace
rising

Numbers from AAA’s Monitoreo Diario chart of 2026-09-02, 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.