Daily Water Watch: Carraízo Back in the Seguridad Band

Day 41 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 40.06 meters — up 83 centimeters from yesterday, and La Plata at 44.36 meters — down 4 centimeters from yesterday.

This is the 37th 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 seguridad, up from observación yesterday. This morning’s chart puts it at 40.06 meters — up 83 centimeters from yesterday, in the seguridad band. The next line on the chart — into the observación band — sits at 39.70 meters, 0.36 meters below this morning’s reading.

La Plata: down 4 cm

La Plata kept sliding. This morning’s chart puts it at 44.36 meters — down 4 centimeters from yesterday, in the ajustes band. The next line on the chart — into the control band — sits at 40.50 meters, 3.86 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

Over the past week Carraízo has been rising an average of 14.3 cm a day, a reversal from a 0.3 cm-a-day decline the week before. Since the rotation began 39 days ago it has gained 253 cm, from 37.53 m. It sits 0.36 m above the observación line (the next band down), at 40.06 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 6 days, around September 24. Nearby USGS gauges recorded 5.18 in of rain this week, most of it September 16 (2.21 in). After the 0.6 in on September 13, the next morning’s reading was +2 cm. After the 1.6 in on September 14, the next morning’s reading was +9 cm.

Over the past week La Plata has been rising an average of 3.7 cm a day, a reversal from a 5.5 cm-a-day decline the week before. Since the rotation began 39 days ago it has lost 202 cm, from 46.38 m. It sits 3.86 m above the control line (the next band down), at 44.36 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 15 days, around October 2. Nearby USGS gauges recorded 2.13 in of rain this week, most of it September 14 (1.09 in). After the 1.09 in on September 14, the next morning’s reading was +6 cm. After the 0.6 in on September 16, the next morning’s reading was -4 cm.

Over the past week Cidra has been rising an average of 3 cm a day. That is 3 straight mornings higher, +19 cm in all. Since the rotation began 39 days ago it has gained 32 cm, from 400.13 m. It sits 0.22 m above the ajustes line (the next band down), at 400.45 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 42 days, around October 29. Nearby USGS gauges recorded 4.68 in of rain this week, most of it September 16 (2.19 in). After the 1.6 in on September 14, the next morning’s reading was +1 cm. After the 2.19 in on September 16, the next morning’s reading was +17 cm.

What to watch

• Carraízo: whether the rise survives a dry week — this week’s gain came with 5.18 in of rain nearby.
• La Plata: whether the rise survives a dry week — this week’s gain came with 2.13 in of rain nearby.
• Cidra: whether the rise survives a dry week — this week’s gain came with 4.68 in of rain nearby.

The other rationing reservoir

Numbers from AAA’s Monitoreo Diario chart of 2026-09-17, 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.