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Reservoirs

Levels for the 19 reservoirs on AAA's daily bulletin

Río Blanco

Naguabo

Observation

24.67m

80.94 ft

0.42 m above Operational adjustments

Data as of August 23, 2026 · Reading taken at 5:00 AM

Compared with normal

3.75 m below normal for this date

A ±7-day window around August 23, 2026, this reservoir's own most recent reading.

Percentile 13 across 16 years of record.

Rank 31 of 241 readings from these dates. Rank 1 is the lowest.

The rank counts individual readings, not years.

Most recent year lower on this date: 2015.

Median
28.42 m
Minimum
22.63 m2010
Maximum
28.83 m2017
90th percentile
28.73 m

Level over time

Resolution follows the range: daily up to a year, weekly at five years, monthly across the whole record.

Río Blanco: level from July 25, 2026 to August 23, 2026, a net fall of 1.95 m.

August 23, 2026: 24.67 m.

Hover the chart or use the arrow keys to read a point.

From July 25, 2026 to August 23, 2026. Minimum 24.67 m, maximum 26.62 m.

The vertical scale runs from 24.50 m to 27.00 m and does not start at zero: these are metres above sea level.

The dashed lines are the alert bounds AAA publishes today. The record keeps no history of those bounds, so we do not know whether they were the same in the past.

Today the reservoir is in Observation.

4 bounds fall outside this chart’s scale.

Río Blanco: level from July 25, 2026 to August 23, 2026, a net fall of 1.95 m.
Datem
July 25, 202626.62
July 26, 202626.55
July 27, 202626.49
July 28, 202626.41
July 29, 202626.33
July 30, 202626.26
July 31, 202626.18
August 1, 202626.09
August 2, 202626.01
August 3, 202625.94
August 4, 202625.87
August 5, 202625.82
August 6, 202625.74
August 7, 202625.64
August 8, 202625.53
August 9, 202625.46
August 10, 202625.40
August 11, 202625.33
August 12, 202625.36
August 13, 202625.29
August 14, 202625.22
August 15, 202625.16
August 16, 202625.07
August 17, 202625.01
August 18, 202624.94
August 19, 202624.86
August 20, 202624.84
August 21, 202624.79
August 22, 202624.74
August 23, 202624.67

Projection

Disabled

This portal does not publish projections yet. Saying when a reservoir would reach its next phase is a claim about the future of a great many people's water, and before publishing one we want the rule for when it may and may not be made written down.

Every August 23 in the record

Compare another date

Hover the dots or use the arrow keys.

2 years of the 17 with a reading on August 23 were below the most recent level.

From 2010 to 2026.

The dashed line is this reservoir’s most recent level: 24.67 m on August 23, 2026.

The vertical scale runs from 22.00 m to 30.00 m and does not start at zero: these are metres above sea level.

Years with no reading on this date are not in the record and are left as empty space on the axis.

Years below the most recent level are marked with a filled dot.

This counts years. The rank in the block above counts readings.

2 years of the 17 with a reading on August 23 were below the most recent level.
Every August 23 in the recordm
201022.86
201127.82
201227.82
201328.37
201428.75
201522.85
201628.77
201728.66
201827.37
201926.45
202028.52
202128.45
202228.77
202328.51
202428.62
202528.24
202624.67

When it has been in each phase

Hover the bands or use the arrow keys.

Each band is one run in one phase, since January 1, 2020.

The axis is calendar time, from January 1, 2020 to August 23, 2026. Stretches with no bulletin are left blank.

Current run

28 days in Observation, since July 27, 2026.

The longest run in Observation on record: 84 days, from September 24, 2010 to December 16, 2010.

Counts bulletin days, not calendar days.

Each band is one run in one phase, since January 1, 2020.
PhaseFromToBulletin days
SafetyJanuary 1, 2020January 7, 20207
OverflowJanuary 8, 2020January 18, 202011
SafetyJanuary 19, 2020January 19, 20201
OverflowJanuary 20, 2020January 27, 20208
SafetyJanuary 28, 2020January 31, 20204
OverflowFebruary 1, 2020February 20, 202020
SafetyFebruary 21, 2020February 26, 20206
OverflowFebruary 27, 2020February 27, 20201
SafetyFebruary 28, 2020March 22, 202024
OverflowMarch 23, 2020March 30, 20208
SafetyMarch 31, 2020April 11, 202012
OverflowApril 12, 2020May 6, 202025
SafetyMay 7, 2020May 14, 20208
OverflowMay 15, 2020May 25, 202011
SafetyMay 26, 2020July 23, 202059
OverflowJuly 24, 2020July 25, 20202
SafetyJuly 26, 2020September 2, 202039
OverflowSeptember 3, 2020September 26, 202024
SafetySeptember 27, 2020September 27, 20201
OverflowSeptember 28, 2020October 18, 202021
SafetyOctober 19, 2020October 25, 20207
OverflowOctober 26, 2020October 30, 20205
SafetyOctober 31, 2020November 8, 20209
OverflowNovember 9, 2020November 11, 20203
SafetyNovember 12, 2020November 21, 202010
OverflowNovember 22, 2020November 26, 20205
SafetyNovember 27, 2020December 11, 202015
OverflowDecember 12, 2020January 8, 202128
SafetyJanuary 9, 2021January 18, 202110
OverflowJanuary 19, 2021January 25, 20217
SafetyJanuary 26, 2021January 31, 20216
OverflowFebruary 1, 2021February 14, 202114
SafetyFebruary 15, 2021March 2, 202116
OverflowMarch 3, 2021March 6, 20214
SafetyMarch 7, 2021March 13, 20217
OverflowMarch 14, 2021March 16, 20213
SafetyMarch 17, 2021March 27, 202111
OverflowMarch 28, 2021April 10, 202114
SafetyApril 11, 2021June 6, 202157
OverflowJune 7, 2021June 14, 20218
SafetyJune 15, 2021June 26, 202112
OverflowJune 27, 2021July 2, 20216
SafetyJuly 3, 2021July 13, 202111
OverflowJuly 14, 2021July 17, 20214
SafetyJuly 18, 2021August 4, 202118
OverflowAugust 5, 2021August 7, 20213
SafetyAugust 8, 2021October 7, 202161
OverflowOctober 8, 2021October 9, 20212
SafetyOctober 10, 2021October 10, 20211
OverflowOctober 11, 2021October 16, 20216
SafetyOctober 17, 2021October 18, 20212
OverflowOctober 19, 2021October 19, 20211
SafetyOctober 20, 2021October 20, 20211
OverflowOctober 21, 2021October 21, 20211
SafetyOctober 22, 2021November 4, 202114
OverflowNovember 5, 2021November 10, 20216
SafetyNovember 11, 2021November 13, 20213
OverflowNovember 14, 2021November 20, 20217
SafetyNovember 21, 2021November 25, 20215
OverflowNovember 26, 2021December 6, 202111
SafetyDecember 7, 2021December 11, 20215
OverflowDecember 12, 2021December 27, 202116
SafetyDecember 28, 2021February 6, 202241
OverflowFebruary 7, 2022February 10, 20224
SafetyFebruary 11, 2022February 11, 20221
OverflowFebruary 12, 2022February 15, 20224
SafetyFebruary 16, 2022February 18, 20223
OverflowFebruary 19, 2022March 3, 202213
SafetyMarch 4, 2022March 6, 20223
OverflowMarch 7, 2022March 11, 20225
SafetyMarch 12, 2022March 12, 20221
OverflowMarch 13, 2022March 14, 20222
SafetyMarch 15, 2022March 24, 20229
OverflowMarch 25, 2022March 27, 20223
SafetyMarch 28, 2022April 6, 202210
OverflowApril 7, 2022April 9, 20223
SafetyApril 10, 2022July 13, 202295
OverflowJuly 14, 2022July 16, 20223
SafetyJuly 17, 2022July 21, 20225
OverflowJuly 22, 2022July 22, 20221
SafetyJuly 23, 2022July 23, 20221
OverflowJuly 24, 2022July 25, 20222
SafetyJuly 26, 2022July 27, 20222
OverflowJuly 28, 2022July 28, 20221
SafetyJuly 29, 2022August 21, 202224
OverflowAugust 22, 2022August 23, 20222
SafetyAugust 24, 2022August 26, 20223
OverflowAugust 27, 2022August 28, 20222
SafetyAugust 29, 2022September 4, 20227
OverflowSeptember 5, 2022September 5, 20221
SafetySeptember 6, 2022September 18, 202213
OverflowSeptember 19, 2022September 20, 20222
SafetySeptember 21, 2022September 22, 20222
OverflowSeptember 23, 2022September 27, 20225
SafetySeptember 28, 2022September 29, 20222
OverflowSeptember 30, 2022October 2, 20223
SafetyOctober 3, 2022October 3, 20221
OverflowOctober 4, 2022October 6, 20223
SafetyOctober 7, 2022October 9, 20223
OverflowOctober 10, 2022October 11, 20222
SafetyOctober 12, 2022October 18, 20227
OverflowOctober 19, 2022October 19, 20221
SafetyOctober 20, 2022November 8, 202220
OverflowNovember 9, 2022November 10, 20222
SafetyNovember 11, 2022November 15, 20225
OverflowNovember 16, 2022November 17, 20222
SafetyNovember 18, 2022December 2, 202215
OverflowDecember 3, 2022December 3, 20221
SafetyDecember 4, 2022December 5, 20222
OverflowDecember 6, 2022December 6, 20221
SafetyDecember 7, 2022December 17, 202211
OverflowDecember 18, 2022January 14, 202328
SafetyJanuary 15, 2023January 15, 20231
OverflowJanuary 16, 2023January 18, 20233
SafetyJanuary 19, 2023January 30, 202312
OverflowJanuary 31, 2023February 21, 202322
SafetyFebruary 22, 2023February 25, 20234
OverflowFebruary 26, 2023February 27, 20232
SafetyFebruary 28, 2023June 29, 2023122
OverflowJune 30, 2023July 1, 20232
SafetyJuly 2, 2023July 12, 202311
OverflowJuly 13, 2023July 14, 20232
SafetyJuly 15, 2023September 27, 202375
OverflowSeptember 28, 2023September 28, 20231
SafetySeptember 29, 2023September 30, 20232
OverflowOctober 1, 2023October 7, 20237
SafetyOctober 8, 2023October 19, 202312
OverflowOctober 20, 2023October 21, 20232
SafetyOctober 22, 2023October 24, 20233
OverflowOctober 25, 2023November 2, 20239
SafetyNovember 3, 2023November 8, 20236
OverflowNovember 9, 2023November 11, 20233
SafetyNovember 12, 2023November 22, 202311
OverflowNovember 23, 2023November 26, 20234
SafetyNovember 27, 2023December 13, 202317
OverflowDecember 14, 2023December 28, 202315
SafetyDecember 29, 2023January 26, 202429
OverflowJanuary 27, 2024January 28, 20242
SafetyJanuary 29, 2024February 5, 20248
OverflowFebruary 6, 2024February 10, 20245
SafetyFebruary 11, 2024April 14, 202464
OverflowApril 15, 2024April 20, 20246
SafetyApril 21, 2024April 21, 20241
OverflowApril 22, 2024April 26, 20245
SafetyApril 27, 2024April 28, 20242
OverflowApril 29, 2024May 8, 202410
SafetyMay 9, 2024May 18, 202410
OverflowMay 19, 2024June 6, 202419
SafetyJune 7, 2024June 15, 20249
OverflowJune 16, 2024June 16, 20241
SafetyJune 17, 2024June 17, 20241
OverflowJune 18, 2024June 18, 20241
SafetyJune 19, 2024June 19, 20241
OverflowJune 20, 2024June 21, 20242
SafetyJune 22, 2024June 22, 20241
OverflowJune 23, 2024June 27, 20245
SafetyJune 28, 2024July 13, 202416
OverflowJuly 14, 2024July 21, 20248
SafetyJuly 22, 2024August 1, 202411
OverflowAugust 2, 2024August 3, 20242
SafetyAugust 4, 2024August 11, 20248
OverflowAugust 12, 2024August 12, 20241
SafetyAugust 13, 2024August 13, 20241
OverflowAugust 14, 2024August 14, 20241
SafetyAugust 15, 2024September 8, 202425
OverflowSeptember 9, 2024September 12, 20244
SafetySeptember 13, 2024September 13, 20241
OverflowSeptember 14, 2024September 15, 20242
SafetySeptember 16, 2024October 31, 202446
OverflowNovember 1, 2024November 2, 20242
SafetyNovember 3, 2024November 10, 20248
OverflowNovember 11, 2024November 13, 20243
SafetyNovember 14, 2024November 14, 20241
OverflowNovember 15, 2024November 15, 20241
SafetyNovember 16, 2024November 16, 20241
OverflowNovember 17, 2024November 18, 20242
SafetyNovember 19, 2024January 26, 202569
OverflowJanuary 27, 2025January 28, 20252
SafetyJanuary 29, 2025February 1, 20254
OverflowMarch 3, 2025March 6, 20254
SafetyMarch 7, 2025March 13, 20257
OverflowMarch 14, 2025March 19, 20256
SafetyMarch 20, 2025April 5, 202517
OverflowApril 6, 2025April 7, 20252
SafetyApril 8, 2025April 8, 20251
OverflowApril 9, 2025April 9, 20251
SafetyApril 10, 2025April 10, 20251
OverflowApril 11, 2025April 11, 20251
SafetyApril 12, 2025April 12, 20251
OverflowApril 13, 2025April 14, 20252
SafetyApril 15, 2025April 17, 20253
OverflowApril 18, 2025April 23, 20256
SafetyApril 24, 2025April 26, 20253
OverflowApril 27, 2025May 5, 20259
SafetyMay 6, 2025May 10, 20255
OverflowMay 11, 2025May 18, 20258
SafetyMay 19, 2025June 8, 202521
OverflowJune 9, 2025June 14, 20256
SafetyJune 15, 2025June 19, 20255
OverflowJune 20, 2025June 22, 20253
SafetyJune 23, 2025June 27, 20255
OverflowJune 28, 2025June 28, 20251
SafetyJune 29, 2025July 1, 20253
OverflowJuly 2, 2025July 5, 20254
SafetyJuly 6, 2025July 20, 202515
OverflowJuly 21, 2025July 25, 20255
SafetyJuly 26, 2025July 27, 20252
OverflowJuly 28, 2025July 28, 20251
SafetyJuly 29, 2025August 2, 20255
OverflowAugust 3, 2025August 5, 20253
SafetyAugust 6, 2025August 6, 20251
OverflowAugust 7, 2025August 7, 20251
SafetyAugust 8, 2025August 9, 20252
OverflowAugust 10, 2025August 11, 20252
SafetyAugust 12, 2025September 7, 202527
OverflowSeptember 8, 2025September 10, 20253
SafetySeptember 11, 2025December 22, 2025103
OverflowDecember 23, 2025December 28, 20256
SafetyDecember 29, 2025February 2, 202636
OverflowFebruary 3, 2026February 5, 20263
SafetyFebruary 6, 2026May 19, 2026103
OverflowMay 20, 2026May 28, 20269
SafetyMay 29, 2026July 26, 202659
ObservationJuly 27, 2026August 23, 202628

How we read the data

Every figure on this portal is the 5:00 AM AST reading from the USGS gauge, every day, at every reservoir. AAA's daily bulletin is drawn at 4:55 AM and carries the freshest reading that had arrived by press time; the gauges transmit once an hour, and the 5:00 AM reading is published around 5:57 AM. On days when levels move quickly the two figures can therefore differ by about a centimetre. Each is correct for its own cut-off. Ours holds the same 24-hour interval every day, which is what makes our day-over-day changes directly comparable to one another.

We read the same USGS gauges that underpin the bulletin. The alert phases (Overflow, Safety, Observation, Operational adjustments, Control) are the thresholds AAA publishes for each reservoir; AAA prints them in Spanish, as Desborde, Seguridad, Observación, Ajustes and Control.

Source

Data: U.S. Geological Survey (USGS)

Provisional data

Provisional data: values are preliminary, have not been reviewed or approved by the U.S. Geological Survey, and are subject to revision or removal as the record is finalized. Do not use them for decisions involving personal or public safety, or property.

Daily reservoir level bulletin: Autoridad de Acueductos y Alcantarillados de Puerto Rico.

This portal is not an official channel of the Autoridad de Acueductos y Alcantarillados. For service notices, consult AAA.