Open water-data platform · 11 countries
Reservoir water levels, worldwide
Live storage and fill levels for 1,942 reservoirs, drawn from official hydrological sources across 11 countries — checked daily.
11
Countries tracked
1,942
Reservoirs tracked
50.6%
Global average fill
145
At critically low levels
1,357 km³
Combined capacity
Updated Jul 27, 2026 · 1,858 reservoirs reporting
Reservoirs.EARTH tracks how full the world’s reservoirs are. We collect official storage readings from national hydrological agencies and turn them into clear, comparable fill levels, multi-year trends and seasonal context — so anyone can see, at a glance, whether a dam is filling up or drying out. Every figure links back to its source, and we check for new official readings every day.
Countries covered
Click to explore · Ctrl + scroll to zoomLoading map…
MITECO official data
Spain
Average fill
73.4%
401 reservoirs
SNIRH official data
Portugal
Average fill
85.0%
51 reservoirs
USGS NWIS data
United States
Average fill
62.0%
515 reservoirs
ONS official data
Brazil
Average fill
75.2%
102 reservoirs
CWC official data
India
Average fill
35.3%
307 reservoirs
DWS official data
South Africa
Average fill
96.3%
218 reservoirs
IRSA official data
Pakistan
Average fill
79.7%
3 reservoirs
BOM official data
Australia
Average fill
60.6%
281 reservoirs
XM data · energy (GWh)
Colombia
Average fill
80.6%
24 reservoirs
WRA official data
Taiwan
Average fill
58.3%
22 reservoirs
NVE data · energy (TWh)
Norway
Average fill
62.0%
5 price areas
Right now around the world
Sizeable reservoirs with a reading in the last 30 days.
Lowest levels
Closest to empty
Reservoir Transparency Index
How openly does your country publish its water data?
We scored 194 countries on the openness of their reservoir reporting. See the rankings, grades and methodology.
Built on official data
Every reading comes from a national hydrological authority — never estimated or crowd-sourced.
From The Reservoir
All articles →Jul 27, 2026 · 9
Lake Mead and Lake Powell Water Levels, July 2026: The Colorado River's Two Giants Are Near Record Lows
The two largest reservoirs in the United States sit on the same river, and both are running near empty. As of 21 July 2026, Lake Mead — behind Hoover Dam — is 25.1% full and Lake Powell, behind Glen Canyon Dam upstream, is 21.8% full, together holding about 23.5% of their combined 65.7 km³ capacity. Powell is the sharper emergency: at its lowest late-July level in five years and within a point of its 2023 record low, some 10 points below its July norm after another weak Rocky Mountain snowpack — and this low in the month it is normally fullest. Mead, at 25.1%, is all but tied with its summer-2022 record and drifting lower through the draw-down. These two hold most of the Colorado River's storage, the water bank for roughly 40 million people, and it is a quarter full — which is exactly why Arizona reads a comfortable 84% while Nevada reads 29%: the full-looking reservoirs downstream are held near the top by design, and the real water is here.
Jul 23, 2026 · 8
India Reservoir Levels, Week of 23 July 2026: Monsoon Refill Lifts Storage to 31% as the Rains Move East
India's tracked reservoirs added 7.2 km³ in the fourth week of July, lifting the same-source national fill from 27.9% to 31.2% between the Central Water Commission's July 16 and July 23 bulletins. Where last week's gains were concentrated in Maharashtra's Pune-area dams, this week the monsoon band did its clearest work in the east and centre: Hirakud (Odisha) jumped 30% to 41%, Hasdeo Bango (Chhattisgarh) 59% to 73%, and the northern giants Bhakra and Pong added three points each. 88 of 149 reservoirs rose. The exception is the southern Krishna basin, where Nagarjuna Sagar sits at 3.2% of live storage — the emptiest big reservoir in the country — and Andhra Pradesh's tracked set is still losing water. At 31% full, national storage has climbed about ten points off its pre-monsoon floor over two strong weeks, with the back half of the monsoon still to run.
Jul 22, 2026 · 8
Colombia Reservoir Levels, July 2026: 79% Full — the Country's Battery, and Bogotá's Tap
Colombia's hydropower reservoirs are 79% full as of 21 July 2026 — 13,822 of 17,440 GWh of storable electricity, a shade above the mid-July norm and about 1.5 points below a year ago. In a grid where hydropower is roughly two-thirds of generation, that number is a power-price gauge before it is a water gauge: XM publishes it daily, and it is the same figure that nearly triggered rationing during the 2023–24 El Niño. The two giants carry it — El Peñol–Guatapé at 90.5% and Guavio at 97.3%, together a quarter of national storage. The soft spot is the Chingaza system that supplies Bogotá's drinking water, in the 60s — the one large storage where a low reading is a water-supply story, not just a power one. With XM flagging renewed El Niño alerts in May 2026, the number to watch is what the reservoirs hold going into the dry season.
Frequently asked questions
How often is the data updated?
We check every official source daily, but each agency publishes at its own pace — some daily (e.g. the USGS and Australia’s BOM), others weekly (e.g. India’s CWC and South Africa’s DWS). The exact date of the latest reading is shown on every reservoir page.
Where does the data come from?
National hydrological and energy agencies: USGS (United States), MITECO and embalses.net (Spain), ONS (Brazil), CWC (India), DWS (South Africa), IRSA (Pakistan), the Bureau of Meteorology (Australia), SNIRH (Portugal), XM (Colombia) and NVE (Norway).
What does the fill level percentage mean?
It is the share of a reservoir’s total capacity currently in storage. 100% means full; below about 20% is considered critically low.
Which countries are covered?
Spain, Portugal, the United States, Brazil, India, South Africa, Pakistan, Australia, Colombia, Norway and Taiwan — with more being added over time.
Is reservoirs.earth free to use?
Yes. It is an open platform and every figure links back to its official source. You can also embed our Reservoir Transparency Index widgets.