Daily Water Watch: La Plata Rises to 44.70 m

Day 45 of the metro rotation plan — interruptions paused since September 2, AAA has not canceled 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: Nov 15 — a projection, not a forecast; one wet afternoon moves it).

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.

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

Numbers from AAA’s Monitoreo Diario chart of Sep 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 Aug 8, when the metro rotation took effect. Straight-line dates are arithmetic, not forecasts.