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Daily Water Watch: La Plata at 43.71 Meters

Published Oct 5, 2026, 7:42 AM787daily · Original analysis

Our coverage

San Juan's rationing plan, zones and calendar

This morning’s 5:00 chart from the Autoridad de Acueductos y Alcantarillados shows Carraízo at 40.72 meters — down 2 centimeters from yesterday. La Plata is at 43.71 meters — down 8 centimeters from yesterday.

Service today

Day 60 of the metro rotation, the San Juan area’s rationing schedule — interruptions paused since September 2, and AAA has not cancelled it.

AAA’s Cedro Arriba plan in Naranjito is in effect: Zone C and Zone D take turns every 48 hours; Zone C has water until Tuesday at 6:00 AM. AAA’s notice.

Most important now

Nothing else AAA has posted is important right now.

Every notice AAA posts is on the water page, in its own words.

Reservoirs

Carraízo: down 2 cm

Carraízo kept sliding. This morning’s chart puts it at 40.72 meters — down 2 centimeters from yesterday, in the Safe band (Seguridad). The next line on the chart — into the Watch band (Observación) — sits at 39.70 meters, 1.02 meters below this morning’s reading.

Adjustments Watch Safe 37.0 37.5 38.0 38.5 39.0 39.5 40.0 40.5 41.0 Aug 7 Sep 5 Oct 5 Aug 8, 37.58 m, USGS gauge at 5 AM, AdjustmentsOct 3, 40.70 m, USGS gauge at 5 AM, Safe Aug 7, 37.64 m, AdjustmentsAug 9, 37.53 m, −5 cm, AdjustmentsAug 10, 37.48 m, −5 cm, AdjustmentsAug 11, 37.43 m, −5 cm, AdjustmentsAug 12, 37.53 m, +10 cm, AdjustmentsAug 13, 37.79 m, +26 cm, AdjustmentsAug 14, 37.86 m, +7 cm, AdjustmentsAug 15, 37.85 m, −1 cm, AdjustmentsAug 16, 37.82 m, −3 cm, AdjustmentsAug 17, 37.76 m, −6 cm, AdjustmentsAug 18, 37.69 m, −7 cm, AdjustmentsAug 19, 37.63 m, −6 cm, AdjustmentsAug 20, 37.57 m, −6 cm, AdjustmentsAug 21, 37.52 m, −5 cm, AdjustmentsAug 22, 37.46 m, −6 cm, AdjustmentsAug 23, 37.41 m, −5 cm, AdjustmentsAug 24, 37.34 m, −7 cm, AdjustmentsAug 25, 37.32 m, −2 cm, AdjustmentsAug 26, 37.30 m, −2 cm, AdjustmentsAug 27, 37.26 m, −4 cm, AdjustmentsAug 28, 37.20 m, −6 cm, AdjustmentsAug 29, 37.14 m, −6 cm, AdjustmentsAug 30, 37.07 m, −7 cm, AdjustmentsAug 31, 37.14 m, +7 cm, AdjustmentsSep 1, 37.20 m, +6 cm, AdjustmentsSep 2, 38.92 m, +172 cm, WatchSep 3, 39.11 m, +19 cm, WatchSep 4, 39.09 m, −2 cm, WatchSep 5, 39.01 m, −8 cm, WatchSep 6, 38.94 m, −7 cm, WatchSep 7, 38.87 m, −7 cm, WatchSep 8, 38.83 m, −4 cm, WatchSep 9, 39.02 m, +19 cm, WatchSep 10, 39.07 m, +5 cm, WatchSep 11, 39.20 m, +13 cm, WatchSep 12, 39.19 m, −1 cm, WatchSep 13, 39.14 m, −5 cm, WatchSep 14, 39.16 m, +2 cm, WatchSep 15, 39.25 m, +9 cm, WatchSep 16, 39.23 m, −2 cm, WatchSep 17, 40.06 m, +83 cm, SafeSep 18, 40.64 m, +58 cm, SafeSep 19, 40.80 m, +16 cm, SafeSep 20, 40.81 m, +1 cm, SafeSep 21, 40.79 m, −2 cm, SafeSep 22, 40.75 m, −4 cm, SafeSep 23, 40.70 m, −5 cm, SafeSep 24, 40.68 m, −2 cm, SafeSep 25, 40.68 m, +0 cm, SafeSep 26, 40.67 m, −1 cm, SafeSep 27, 40.63 m, −4 cm, SafeSep 28, 40.58 m, −5 cm, SafeSep 29, 40.53 m, −5 cm, SafeSep 30, 40.51 m, −2 cm, SafeOct 1, 40.47 m, −4 cm, SafeOct 2, 40.60 m, +13 cm, SafeOct 4, 40.74 m, +4 cm, SafeOct 5, 40.72 m, −2 cm, Safe 40.72 m Sep 29, 0.28 in of rainSep 30, 0.53 in of rainOct 1, 1.45 in of rainOct 2, 0.01 in of rainOct 3, 0.03 in of rainOct 4, 0.04 in of rain rain to 1.45 in
Carraízo since Aug 7, meters 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).
Show the numbers
  • Aug 8, 37.58 m, USGS gauge at 5 AM, Adjustments
  • Oct 3, 40.70 m, USGS gauge at 5 AM, Safe
  • Aug 7, 37.64 m, Adjustments
  • Aug 9, 37.53 m, −5 cm, Adjustments
  • Aug 10, 37.48 m, −5 cm, Adjustments
  • Aug 11, 37.43 m, −5 cm, Adjustments
  • Aug 12, 37.53 m, +10 cm, Adjustments
  • Aug 13, 37.79 m, +26 cm, Adjustments
  • Aug 14, 37.86 m, +7 cm, Adjustments
  • Aug 15, 37.85 m, −1 cm, Adjustments
  • Aug 16, 37.82 m, −3 cm, Adjustments
  • Aug 17, 37.76 m, −6 cm, Adjustments
  • Aug 18, 37.69 m, −7 cm, Adjustments
  • Aug 19, 37.63 m, −6 cm, Adjustments
  • Aug 20, 37.57 m, −6 cm, Adjustments
  • Aug 21, 37.52 m, −5 cm, Adjustments
  • Aug 22, 37.46 m, −6 cm, Adjustments
  • Aug 23, 37.41 m, −5 cm, Adjustments
  • Aug 24, 37.34 m, −7 cm, Adjustments
  • Aug 25, 37.32 m, −2 cm, Adjustments
  • Aug 26, 37.30 m, −2 cm, Adjustments
  • Aug 27, 37.26 m, −4 cm, Adjustments
  • Aug 28, 37.20 m, −6 cm, Adjustments
  • Aug 29, 37.14 m, −6 cm, Adjustments
  • Aug 30, 37.07 m, −7 cm, Adjustments
  • Aug 31, 37.14 m, +7 cm, Adjustments
  • Sep 1, 37.20 m, +6 cm, Adjustments
  • Sep 2, 38.92 m, +172 cm, Watch
  • Sep 3, 39.11 m, +19 cm, Watch
  • Sep 4, 39.09 m, −2 cm, Watch
  • Sep 5, 39.01 m, −8 cm, Watch
  • Sep 6, 38.94 m, −7 cm, Watch
  • Sep 7, 38.87 m, −7 cm, Watch
  • Sep 8, 38.83 m, −4 cm, Watch
  • Sep 9, 39.02 m, +19 cm, Watch
  • Sep 10, 39.07 m, +5 cm, Watch
  • Sep 11, 39.20 m, +13 cm, Watch
  • Sep 12, 39.19 m, −1 cm, Watch
  • Sep 13, 39.14 m, −5 cm, Watch
  • Sep 14, 39.16 m, +2 cm, Watch
  • Sep 15, 39.25 m, +9 cm, Watch
  • Sep 16, 39.23 m, −2 cm, Watch
  • Sep 17, 40.06 m, +83 cm, Safe
  • Sep 18, 40.64 m, +58 cm, Safe
  • Sep 19, 40.80 m, +16 cm, Safe
  • Sep 20, 40.81 m, +1 cm, Safe
  • Sep 21, 40.79 m, −2 cm, Safe
  • Sep 22, 40.75 m, −4 cm, Safe
  • Sep 23, 40.70 m, −5 cm, Safe
  • Sep 24, 40.68 m, −2 cm, Safe
  • Sep 25, 40.68 m, +0 cm, Safe
  • Sep 26, 40.67 m, −1 cm, Safe
  • Sep 27, 40.63 m, −4 cm, Safe
  • Sep 28, 40.58 m, −5 cm, Safe
  • Sep 29, 40.53 m, −5 cm, Safe
  • Sep 30, 40.51 m, −2 cm, Safe
  • Oct 1, 40.47 m, −4 cm, Safe
  • Oct 2, 40.60 m, +13 cm, Safe
  • Oct 4, 40.74 m, +4 cm, Safe
  • Oct 5, 40.72 m, −2 cm, Safe
  • Sep 29, 0.28 in of rain
  • Sep 30, 0.53 in of rain
  • Oct 1, 1.45 in of rain
  • Oct 2, 0.01 in of rain
  • Oct 3, 0.03 in of rain
  • Oct 4, 0.04 in of rain

Carraízo, October 5

Level today
40.72 mSafe band
Change since yesterday
−2 cm
To the Watch line
1.02 mline at 39.70 m
At this week's pace
rising

La Plata: down 8 cm

La Plata kept sliding. This morning’s chart puts it at 43.71 meters — down 8 centimeters from yesterday, in the Adjustments band (Ajustes). The next line on the chart — into the Control band — sits at 40.50 meters, 3.21 meters below this morning’s reading. At this week’s pace that is about 38 days away (straight-line date: November 12 — a projection, not a forecast; one wet afternoon moves it).

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.

Adjustments Watch Safe 40 42 44 46 48 50 52 Aug 7 Sep 5 Oct 5 Aug 8, 46.46 m, USGS gauge at 5 AM, WatchOct 3, 43.87 m, USGS gauge at 5 AM, Adjustments Aug 7, 46.55 m, WatchAug 9, 46.38 m, −8 cm, WatchAug 10, 46.29 m, −9 cm, WatchAug 11, 46.20 m, −9 cm, WatchAug 12, 46.16 m, −4 cm, WatchAug 13, 46.11 m, −5 cm, WatchAug 14, 46.02 m, −9 cm, WatchAug 15, 45.95 m, −7 cm, WatchAug 16, 45.88 m, −7 cm, WatchAug 17, 45.80 m, −8 cm, WatchAug 18, 45.71 m, −9 cm, WatchAug 19, 45.62 m, −9 cm, WatchAug 20, 45.55 m, −7 cm, WatchAug 21, 45.49 m, −6 cm, WatchAug 22, 45.42 m, −7 cm, WatchAug 23, 45.35 m, −7 cm, WatchAug 24, 45.28 m, −7 cm, WatchAug 25, 45.23 m, −5 cm, WatchAug 26, 45.15 m, −8 cm, WatchAug 27, 45.04 m, −11 cm, WatchAug 28, 44.93 m, −11 cm, WatchAug 29, 44.83 m, −10 cm, AdjustmentsAug 30, 44.72 m, −11 cm, AdjustmentsAug 31, 44.67 m, −5 cm, AdjustmentsSep 1, 44.59 m, −8 cm, AdjustmentsSep 2, 44.59 m, +0 cm, AdjustmentsSep 3, 44.59 m, +0 cm, AdjustmentsSep 4, 44.57 m, −2 cm, AdjustmentsSep 5, 44.54 m, −3 cm, AdjustmentsSep 6, 44.52 m, −2 cm, AdjustmentsSep 7, 44.46 m, −6 cm, AdjustmentsSep 8, 44.40 m, −6 cm, AdjustmentsSep 9, 44.32 m, −8 cm, AdjustmentsSep 10, 44.24 m, −8 cm, AdjustmentsSep 11, 44.14 m, −10 cm, AdjustmentsSep 12, 44.25 m, +11 cm, AdjustmentsSep 13, 44.26 m, +1 cm, AdjustmentsSep 14, 44.40 m, +14 cm, AdjustmentsSep 15, 44.46 m, +6 cm, AdjustmentsSep 16, 44.40 m, −6 cm, AdjustmentsSep 17, 44.36 m, −4 cm, AdjustmentsSep 18, 44.40 m, +4 cm, AdjustmentsSep 19, 44.61 m, +21 cm, AdjustmentsSep 20, 44.66 m, +5 cm, AdjustmentsSep 21, 44.70 m, +4 cm, AdjustmentsSep 22, 44.72 m, +2 cm, AdjustmentsSep 23, 44.68 m, −4 cm, AdjustmentsSep 24, 44.63 m, −5 cm, AdjustmentsSep 25, 44.56 m, −7 cm, AdjustmentsSep 26, 44.47 m, −9 cm, AdjustmentsSep 27, 44.39 m, −8 cm, AdjustmentsSep 28, 44.31 m, −8 cm, AdjustmentsSep 29, 44.22 m, −9 cm, AdjustmentsSep 30, 44.13 m, −9 cm, AdjustmentsOct 1, 44.04 m, −9 cm, AdjustmentsOct 2, 43.96 m, −8 cm, AdjustmentsOct 4, 43.79 m, −8 cm, AdjustmentsOct 5, 43.71 m, −8 cm, Adjustments 43.71 m at ~9 cm/day Sep 29, 0.22 in of rainSep 30, 0.5 in of rainOct 1, 0.02 in of rainOct 2, 0.01 in of rainOct 3, 0.01 in of rainOct 4, 0.84 in of rain rain to 0.84 in
La Plata since Aug 7, meters 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).
Show the numbers
  • Aug 8, 46.46 m, USGS gauge at 5 AM, Watch
  • Oct 3, 43.87 m, USGS gauge at 5 AM, Adjustments
  • Aug 7, 46.55 m, Watch
  • Aug 9, 46.38 m, −8 cm, Watch
  • Aug 10, 46.29 m, −9 cm, Watch
  • Aug 11, 46.20 m, −9 cm, Watch
  • Aug 12, 46.16 m, −4 cm, Watch
  • Aug 13, 46.11 m, −5 cm, Watch
  • Aug 14, 46.02 m, −9 cm, Watch
  • Aug 15, 45.95 m, −7 cm, Watch
  • Aug 16, 45.88 m, −7 cm, Watch
  • Aug 17, 45.80 m, −8 cm, Watch
  • Aug 18, 45.71 m, −9 cm, Watch
  • Aug 19, 45.62 m, −9 cm, Watch
  • Aug 20, 45.55 m, −7 cm, Watch
  • Aug 21, 45.49 m, −6 cm, Watch
  • Aug 22, 45.42 m, −7 cm, Watch
  • Aug 23, 45.35 m, −7 cm, Watch
  • Aug 24, 45.28 m, −7 cm, Watch
  • Aug 25, 45.23 m, −5 cm, Watch
  • Aug 26, 45.15 m, −8 cm, Watch
  • Aug 27, 45.04 m, −11 cm, Watch
  • Aug 28, 44.93 m, −11 cm, Watch
  • Aug 29, 44.83 m, −10 cm, Adjustments
  • Aug 30, 44.72 m, −11 cm, Adjustments
  • Aug 31, 44.67 m, −5 cm, Adjustments
  • Sep 1, 44.59 m, −8 cm, Adjustments
  • Sep 2, 44.59 m, +0 cm, Adjustments
  • Sep 3, 44.59 m, +0 cm, Adjustments
  • Sep 4, 44.57 m, −2 cm, Adjustments
  • Sep 5, 44.54 m, −3 cm, Adjustments
  • Sep 6, 44.52 m, −2 cm, Adjustments
  • Sep 7, 44.46 m, −6 cm, Adjustments
  • Sep 8, 44.40 m, −6 cm, Adjustments
  • Sep 9, 44.32 m, −8 cm, Adjustments
  • Sep 10, 44.24 m, −8 cm, Adjustments
  • Sep 11, 44.14 m, −10 cm, Adjustments
  • Sep 12, 44.25 m, +11 cm, Adjustments
  • Sep 13, 44.26 m, +1 cm, Adjustments
  • Sep 14, 44.40 m, +14 cm, Adjustments
  • Sep 15, 44.46 m, +6 cm, Adjustments
  • Sep 16, 44.40 m, −6 cm, Adjustments
  • Sep 17, 44.36 m, −4 cm, Adjustments
  • Sep 18, 44.40 m, +4 cm, Adjustments
  • Sep 19, 44.61 m, +21 cm, Adjustments
  • Sep 20, 44.66 m, +5 cm, Adjustments
  • Sep 21, 44.70 m, +4 cm, Adjustments
  • Sep 22, 44.72 m, +2 cm, Adjustments
  • Sep 23, 44.68 m, −4 cm, Adjustments
  • Sep 24, 44.63 m, −5 cm, Adjustments
  • Sep 25, 44.56 m, −7 cm, Adjustments
  • Sep 26, 44.47 m, −9 cm, Adjustments
  • Sep 27, 44.39 m, −8 cm, Adjustments
  • Sep 28, 44.31 m, −8 cm, Adjustments
  • Sep 29, 44.22 m, −9 cm, Adjustments
  • Sep 30, 44.13 m, −9 cm, Adjustments
  • Oct 1, 44.04 m, −9 cm, Adjustments
  • Oct 2, 43.96 m, −8 cm, Adjustments
  • Oct 4, 43.79 m, −8 cm, Adjustments
  • Oct 5, 43.71 m, −8 cm, Adjustments
  • Sep 29, 0.22 in of rain
  • Sep 30, 0.5 in of rain
  • Oct 1, 0.02 in of rain
  • Oct 2, 0.01 in of rain
  • Oct 3, 0.01 in of rain
  • Oct 4, 0.84 in of rain

La Plata, October 5

Level today
43.71 mAdjustments band
Change since yesterday
−8 cm
To the Control line
3.21 mline at 40.50 m
At this week's pace
about 38 daysstraight-line date: November 12

The other rationing reservoir

Cidra, October 5

Level today
400.54 mWatch band
Change since yesterday
+1 cm
To the Adjustments line
0.31 mline at 400.23 m
This morning
rising

Outlook

What the numbers say

The week’s clearest story is a split. Carraízo, the big metro reservoir, has reversed course: it was sliding the week before and is now climbing at 3.2 cm a day, helped by a 13 cm jump the morning after October 1’s heavy rain. Today’s 2 cm dip is small against that run. Arithmetic at this week’s pace would carry it into the Spilling band (Desborde) in about 7 days, but a few dry days would stretch that out. La Plata is moving the other way, and rain isn’t helping there. It has fallen 13 straight mornings, and even the October 4 rain was followed by another drop.

Cidra is the quiet one. Its week-long movement is inside chart-reading noise, so effectively flat, though it has taken in the most rain of the three gauges’ areas, 3.54 in. Each wet day nudged it up by a centimetre or two at most, which suggests the rain is roughly offsetting what is drawn out rather than building a cushion. At La Plata’s current pace, the Control line is about 38 days away, around November 12. That is a projection from one week’s trend, not a forecast.

What to watch

  • Carraízo: whether the rise survives a dry week — this week’s gain came with 2.34 in of rain nearby.
  • Río Grande, Canóvanas and Loíza: whether AAA says in public that the east-side rationing is over, and posts that the Canóvanas filtration plant is back in operation.
  • Naranjito: AAA’s Cedro Arriba plan — its calendar runs through October 31; whether AAA extends it, changes the phase or ends it.

Lake levels

The USGS gauge at Carraízo read 40.71 meters at 6:45 AM. The USGS gauge at La Plata read 43.70 meters at 6:45 AM. The USGS gauge at Cidra read 400.54 meters at 6:45 AM.

The gauges report every quarter hour and their readings are provisional; the bands are measured on AAA’s 5:00 chart.

Elsewhere today

How we read the data

This is the 51st Daily Water Watch (yesterday’s is here). The levels update every morning on the water page.

Levels: AAA’s daily reservoir chart, October 5. Rain: USGS gauges within 12 km of each reservoir. Day counts start August 7, when the metro rotation took effect. Straight-line dates are arithmetic, not forecasts. How we report.

Cite this

Source: 787daily, “Daily Water Watch: La Plata at 43.71 Meters”, Oct 5, 2026 — https://787daily.com/news/2026-10-05-daily-water-watch-la-plata-at-43-71-meters/

Numbers from
AAA's 5 AM reservoir chart, validated daily
Use our data
Today (JSON) · Reservoir history (CSV).Free to reuse under CC BY 4.0: credit 787daily.com with a link.

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