Infrastructure

Daily Water Watch: La Plata Rises to 44.70 Meters

Published Sep 21, 2026 · 787 Daily · Original analysis

Day 45 of the metro rotation plan — interruptions paused since September 2, AAA has not cancelled the plan. This morning’s 5:00 chart from the Autoridad de Acueductos y Alcantarillados shows Carraízo at 40.79 meters — down 2 centimeters from yesterday, and La Plata at 44.70 meters — up 4 centimeters from yesterday.

This is the 40th 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 40.79 meters — down 2 centimeters from yesterday, in the seguridad band. The next line on the chart — into the observación band — sits at 39.70 meters, 1.09 meters below this morning’s reading. At AAA’s printed pace that is roughly 54.5 days out (straight-line date: 2026-11-15 — a projection, not a forecast; one wet afternoon moves it).

ajustes observación seguridad 37.0 37.5 38.0 38.5 39.0 39.5 40.0 40.5 41.0 Jul 24 Aug 22 Sep 21 Jul 24 · 38.66 m · USGS gauge, 5 AM · observaciónJul 25 · 38.58 m · USGS gauge, 5 AM · observaciónJul 26 · 38.50 m · USGS gauge, 5 AM · observaciónJul 27 · 38.41 m · USGS gauge, 5 AM · ajustesJul 28 · 38.32 m · USGS gauge, 5 AM · ajustesJul 29 · 38.22 m · USGS gauge, 5 AM · ajustesJul 30 · 38.12 m · USGS gauge, 5 AM · ajustesJul 31 · 38.03 m · USGS gauge, 5 AM · ajustesAug 1 · 37.94 m · USGS gauge, 5 AM · ajustesAug 2 · 37.86 m · USGS gauge, 5 AM · ajustesAug 3 · 37.80 m · USGS gauge, 5 AM · ajustesAug 4 · 37.73 m · USGS gauge, 5 AM · ajustesAug 5 · 37.71 m · USGS gauge, 5 AM · ajustesAug 6 · 37.68 m · USGS gauge, 5 AM · ajustesAug 8 · 37.58 m · USGS gauge, 5 AM · ajustes Aug 7 · 37.64 m · −4 cm · ajustesAug 9 · 37.53 m · −5 cm · ajustesAug 10 · 37.48 m · −5 cm · ajustesAug 11 · 37.43 m · −5 cm · ajustesAug 12 · 37.53 m · +10 cm · ajustesAug 13 · 37.79 m · +26 cm · ajustesAug 14 · 37.86 m · +7 cm · ajustesAug 15 · 37.85 m · −1 cm · ajustesAug 16 · 37.82 m · −3 cm · ajustesAug 17 · 37.76 m · −6 cm · ajustesAug 18 · 37.69 m · −7 cm · ajustesAug 19 · 37.63 m · −6 cm · ajustesAug 20 · 37.57 m · −6 cm · ajustesAug 21 · 37.52 m · −5 cm · ajustesAug 22 · 37.46 m · −6 cm · ajustesAug 23 · 37.41 m · −5 cm · ajustesAug 24 · 37.34 m · −7 cm · ajustesAug 25 · 37.32 m · −2 cm · ajustesAug 26 · 37.30 m · −2 cm · ajustesAug 27 · 37.26 m · −4 cm · ajustesAug 28 · 37.20 m · −6 cm · ajustesAug 29 · 37.14 m · −6 cm · ajustesAug 30 · 37.07 m · −7 cm · ajustesAug 31 · 37.14 m · +7 cm · ajustesSep 1 · 37.20 m · +6 cm · ajustesSep 2 · 38.92 m · +172 cm · observaciónSep 3 · 39.11 m · +19 cm · observaciónSep 4 · 39.09 m · −2 cm · observaciónSep 5 · 39.01 m · −8 cm · observaciónSep 6 · 38.94 m · −7 cm · observaciónSep 7 · 38.87 m · −7 cm · observaciónSep 8 · 38.83 m · −4 cm · observaciónSep 9 · 39.02 m · +19 cm · observaciónSep 10 · 39.07 m · +5 cm · observaciónSep 11 · 39.20 m · +13 cm · observaciónSep 12 · 39.19 m · −1 cm · observaciónSep 13 · 39.14 m · −5 cm · observaciónSep 14 · 39.16 m · +2 cm · observaciónSep 15 · 39.25 m · +9 cm · observaciónSep 16 · 39.23 m · −2 cm · observaciónSep 17 · 40.06 m · +83 cm · seguridadSep 18 · 40.64 m · +58 cm · seguridadSep 19 · 40.80 m · +16 cm · seguridadSep 20 · 40.81 m · +1 cm · seguridadSep 21 · 40.79 m · −2 cm · seguridad 40.79 m at ~2 cm/day Sep 15 · 0.43 in of rainSep 16 · 2.21 in of rainSep 17 · 0.92 in of rainSep 19 · 0.03 in of rain rain to 2.21 in
Carraízo since Jul 24, metres above sea level, shaded by AAA alert band, with daily rain from USGS gauges within 12 km. Data: AAA Monitoreo Diario; hollow points are the USGS gauge's 5 AM reading on days before AAA's record (from Aug 7).

Carraízo · September 21

Level today
40.79 mband: seguridad
Change since yesterday
-2 cm
To the observación line
1.09 mline at 39.70 m
At the current pace
≈ 54.5 daysstraight-line date: 2026-11-15

La Plata: a rise

La Plata gained ground overnight. This morning’s chart puts it at 44.70 meters — up 4 centimeters from yesterday, in the ajustes band. The next line on the chart — into the control band — sits at 40.50 meters, 4.20 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.

ajustes observación seguridad 40 42 44 46 48 50 52 Jul 24 Aug 22 Sep 21 Jul 24 · 47.66 m · USGS gauge, 5 AM · observaciónJul 25 · 47.58 m · USGS gauge, 5 AM · observaciónJul 26 · 47.52 m · USGS gauge, 5 AM · observaciónJul 27 · 47.45 m · USGS gauge, 5 AM · observaciónJul 28 · 47.37 m · USGS gauge, 5 AM · observaciónJul 29 · 47.29 m · USGS gauge, 5 AM · observaciónJul 30 · 47.21 m · USGS gauge, 5 AM · observaciónJul 31 · 47.13 m · USGS gauge, 5 AM · observaciónAug 1 · 47.05 m · USGS gauge, 5 AM · observaciónAug 2 · 46.97 m · USGS gauge, 5 AM · observaciónAug 3 · 46.88 m · USGS gauge, 5 AM · observaciónAug 4 · 46.79 m · USGS gauge, 5 AM · observaciónAug 5 · 46.72 m · USGS gauge, 5 AM · observaciónAug 6 · 46.63 m · USGS gauge, 5 AM · observaciónAug 8 · 46.46 m · USGS gauge, 5 AM · observación Aug 7 · 46.55 m · −8 cm · observaciónAug 9 · 46.38 m · −8 cm · observaciónAug 10 · 46.29 m · −9 cm · observaciónAug 11 · 46.20 m · −9 cm · observaciónAug 12 · 46.16 m · −4 cm · observaciónAug 13 · 46.11 m · −5 cm · observaciónAug 14 · 46.02 m · −9 cm · observaciónAug 15 · 45.95 m · −7 cm · observaciónAug 16 · 45.88 m · −7 cm · observaciónAug 17 · 45.80 m · −8 cm · observaciónAug 18 · 45.71 m · −9 cm · observaciónAug 19 · 45.62 m · −9 cm · observaciónAug 20 · 45.55 m · −7 cm · observaciónAug 21 · 45.49 m · −6 cm · observaciónAug 22 · 45.42 m · −7 cm · observaciónAug 23 · 45.35 m · −7 cm · observaciónAug 24 · 45.28 m · −7 cm · observaciónAug 25 · 45.23 m · −5 cm · observaciónAug 26 · 45.15 m · −8 cm · observaciónAug 27 · 45.04 m · −11 cm · observaciónAug 28 · 44.93 m · −11 cm · observaciónAug 29 · 44.83 m · −10 cm · ajustesAug 30 · 44.72 m · −11 cm · ajustesAug 31 · 44.67 m · −5 cm · ajustesSep 1 · 44.59 m · −8 cm · ajustesSep 2 · 44.59 m · +0 cm · ajustesSep 3 · 44.59 m · +0 cm · ajustesSep 4 · 44.57 m · −2 cm · ajustesSep 5 · 44.54 m · −3 cm · ajustesSep 6 · 44.52 m · −2 cm · ajustesSep 7 · 44.46 m · −6 cm · ajustesSep 8 · 44.40 m · −6 cm · ajustesSep 9 · 44.32 m · −8 cm · ajustesSep 10 · 44.24 m · −8 cm · ajustesSep 11 · 44.14 m · −10 cm · ajustesSep 12 · 44.25 m · +11 cm · ajustesSep 13 · 44.26 m · +1 cm · ajustesSep 14 · 44.40 m · +14 cm · ajustesSep 15 · 44.46 m · +6 cm · ajustesSep 16 · 44.40 m · −6 cm · ajustesSep 17 · 44.36 m · −4 cm · ajustesSep 18 · 44.40 m · +4 cm · ajustesSep 19 · 44.61 m · +21 cm · ajustesSep 20 · 44.66 m · +5 cm · ajustesSep 21 · 44.70 m · +4 cm · ajustes 44.70 m Sep 15 · 0.14 in of rainSep 16 · 0.6 in of rainSep 17 · 0.58 in of rainSep 18 · 0.01 in of rainSep 19 · 0.01 in of rain rain to 0.60 in
La Plata since Jul 24, metres above sea level, shaded by AAA alert band, with daily rain from USGS gauges within 12 km. Data: AAA Monitoreo Diario; hollow points are the USGS gauge's 5 AM reading on days before AAA's record (from Aug 7).

La Plata · September 21

Level today
44.70 mband: ajustes
Change since yesterday
+4 cm
To the control line
4.20 mline at 40.50 m
At the current pace
rising

What the numbers say

Over the past week Carraízo has been rising an average of 25.7 cm a day. Since the rotation began 44 days ago it has gained 321 cm, from 37.58 m. It sits 1.09 m above the observación line (the next band down), at 40.79 m in the seguridad band. If this week’s rise held, the level would climb into the desborde band above (line at 40.95 m) in about 1 days, around September 22. Nearby USGS gauges recorded 3.59 in of rain this week, most of it September 16 (2.21 in). After the 2.21 in on September 16, the next morning’s reading was +83 cm. After the 0.92 in on September 17, the next morning’s reading was +58 cm.

Over the past week La Plata has been rising an average of 4 cm a day. That is 4 straight mornings higher, +34 cm in all. Since August 8 it has lost 176 cm, from 46.46 m. It sits 4.20 m above the control line (the next band down), at 44.70 m in the ajustes band. If this week’s rise held, the level would climb into the observacion band above (line at 44.90 m) in about 5 days, around September 26. Nearby USGS gauges recorded 1.34 in of rain this week, most of it September 16 (0.6 in). After the 0.6 in on September 16, the next morning’s reading was -4 cm. After the 0.58 in on September 17, the next morning’s reading was +4 cm.

Over the past week Cidra has been rising an average of 4.5 cm a day. Since August 8 it has gained 39 cm, from 400.15 m. It sits 0.31 m above the ajustes line (the next band down), at 400.54 m in the observación band. If this week’s rise held, the level would climb into the seguridad band above (line at 401.71 m) in about 26 days, around October 17. Nearby USGS gauges recorded 4.45 in of rain this week, most of it September 16 (2.19 in). After the 2.19 in on September 16, the next morning’s reading was +17 cm. After the 1.49 in on September 17, the next morning’s reading was +8 cm.

What to watch

  • Carraízo: whether the rise survives a dry week — this week’s gain came with 3.59 in of rain nearby.
  • La Plata: whether the rise survives a dry week — this week’s gain came with 1.34 in of rain nearby.
  • Cidra: whether the rise survives a dry week — this week’s gain came with 4.45 in of rain nearby.

The other rationing reservoir

Cidra · September 21

Level today
400.54 mband: observación
Change since yesterday
0 cm
To the ajustes line
0.31 mline at 400.23 m
At the current pace
holding

Numbers from AAA’s Monitoreo Diario chart of 2026-09-21, 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.