Infrastructure

Water Week in Review: Carraízo Up 20 cm, September 6–September 13

Published Sep 13, 2026 · 787 Daily · Original analysis

The week of September 6–September 13 on AAA’s reservoir charts: Carraízo up 20 cm, La Plata down 26 cm. The numbers first, then what they add up to.

At a glance

Carraízo

Sep 6 → Sep 13
38.94 → 39.14 mobservación band today
Net change
+20 cm2.9 cm a day on average
Best morning
+19 cmSep 9
Worst morning
−7 cmSep 7
Rain nearby, last 7 days
1.82 inmost on Sep 7 (0.95 in)
Above the ajustes line
0.64 mrising — seguridad line ≈ 12 days up

La Plata

Sep 6 → Sep 13
44.52 → 44.26 majustes band today
Net change
−26 cm3.7 cm a day on average
Best morning
+11 cmSep 12
Worst morning
−10 cmSep 11
Rain nearby, last 7 days
1.63 inmost on Sep 9 (0.55 in)
Above the control line
3.76 m≈ 114 days at this week's pace

Cidra

Sep 6 → Sep 13
400.16 → 400.26 mobservación band today
Net change
+10 cm1.4 cm a day on average
Best morning
+5 cmSep 11
Worst morning
−1 cmSep 13
Rain nearby, last 7 days
4.52 inmost on Sep 10 (1.57 in)
Above the ajustes line
0.03 mrising — seguridad line ≈ 85 days up

Carraízo, this week

Carraízo, morning by morning · tap a day for that chart check

Teal = up from the previous reading, coral = down; a bold border marks a move of 20 cm or more.

Three reservoirs, one scale

0 +26 cm −38 cm Sep 6 Sep 13 Carraízo · 2026-09-06 · 38.94 m · ±0 cm since 2026-09-06Carraízo · 2026-09-07 · 38.87 m · −7 cm since 2026-09-06Carraízo · 2026-09-08 · 38.83 m · −11 cm since 2026-09-06Carraízo · 2026-09-09 · 39.02 m · +8 cm since 2026-09-06Carraízo · 2026-09-10 · 39.07 m · +13 cm since 2026-09-06Carraízo · 2026-09-11 · 39.20 m · +26 cm since 2026-09-06Carraízo · 2026-09-12 · 39.19 m · +25 cm since 2026-09-06Carraízo · 2026-09-13 · 39.14 m · +20 cm since 2026-09-06Carraízo +20 cm La Plata · 2026-09-06 · 44.52 m · ±0 cm since 2026-09-06La Plata · 2026-09-07 · 44.46 m · −6 cm since 2026-09-06La Plata · 2026-09-08 · 44.40 m · −12 cm since 2026-09-06La Plata · 2026-09-09 · 44.32 m · −20 cm since 2026-09-06La Plata · 2026-09-10 · 44.24 m · −28 cm since 2026-09-06La Plata · 2026-09-11 · 44.14 m · −38 cm since 2026-09-06La Plata · 2026-09-12 · 44.25 m · −27 cm since 2026-09-06La Plata · 2026-09-13 · 44.26 m · −26 cm since 2026-09-06La Plata −26 cm Cidra · 2026-09-06 · 400.16 m · ±0 cm since 2026-09-06Cidra · 2026-09-07 · 400.16 m · ±0 cm since 2026-09-06Cidra · 2026-09-08 · 400.16 m · ±0 cm since 2026-09-06Cidra · 2026-09-09 · 400.18 m · +2 cm since 2026-09-06Cidra · 2026-09-10 · 400.22 m · +6 cm since 2026-09-06Cidra · 2026-09-11 · 400.27 m · +11 cm since 2026-09-06Cidra · 2026-09-12 · 400.27 m · +11 cm since 2026-09-06Cidra · 2026-09-13 · 400.26 m · +10 cm since 2026-09-06Cidra +10 cm
Change since Sep 6, in centimeters — three reservoirs on one scale. Hover or tap a point for the day's reading. Data: AAA Monitoreo Diario.

What it adds up to

Carraízo gained the most ground this week, climbing 20 cm to 39.14 m in the observación band on the back of a single 19 cm jump September 9, but that gain has already lost momentum — the 7-day pace has slowed from 30 cm a day the previous week to 4.5 cm a day now, and the reservoir has fallen for the last two mornings. Cidra also ended higher, up 10 cm to 400.26 m, still in observación and sitting just 0.03 m above the ajustes line below it; four straight days of rain, capped by 1.57 in on September 10, kept pushing it up before it ticked down 1 cm on the final morning.

La Plata is the one still sliding: down 26 cm on the week to 44.26 m in the ajustes band, and falling faster than it was the week before despite 1.63 in of rain, which only slowed rather than reversed the drop. It remains 3.76 m above the control line, and at the current rate a projection — arithmetic, not a forecast — puts that line about 114 days out.

Each reservoir against its own next band line
observación 38.6 38.8 39.0 39.2 39.4 39.6 Sep 6 Sep 9 Sep 13 Sep 6 · 38.94 m · 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 · observación 39.14 m — today ▼ at ~5 cm/day
Carraízo since Sep 6, metres above sea level, shaded by AAA alert band. Data: AAA Monitoreo Diario.
ajustes 41 42 43 44 45 Sep 6 Sep 9 Sep 13 Sep 6 · 44.52 m · 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 · ajustes 44.26 m — today ▲
La Plata since Sep 6, metres above sea level, shaded by AAA alert band. Data: AAA Monitoreo Diario.
ajustes observación 398.5 399.0 399.5 400.0 400.5 401.0 401.5 Sep 6 Sep 9 Sep 13 Sep 6 · 400.16 m · ajustesSep 7 · 400.16 m · +0 cm · ajustesSep 8 · 400.16 m · +0 cm · ajustesSep 9 · 400.18 m · +2 cm · ajustesSep 10 · 400.22 m · +4 cm · ajustesSep 11 · 400.27 m · +5 cm · observaciónSep 12 · 400.27 m · +0 cm · observaciónSep 13 · 400.26 m · −1 cm · observación 400.26 m — today ▼ at ~1 cm/day
Cidra since Sep 6, metres above sea level, shaded by AAA alert band. Data: AAA Monitoreo Diario.
All 8 daily chart checks this week

Numbers from AAA’s Monitoreo Diario charts, read each morning for our reservoir board; rain from USGS gauges within 12 km of each reservoir (a proximity proxy, not a basin measurement). Rates and pace dates are arithmetic over the stored readings, not forecasts. The narrative is drafted by Claude from the computed figures and checked number-by-number against them before publishing.