Every number has an open file.
The files behind everything on this site are here. Download them and use them in your own work. The data itself is produced by İSKİ and the other sources; we combine it into one consistent shape.
Files you can download.
Citywide daily fill level
- Rows
- 8,894
- Period
- 23 October 2000 – 6 November 2026
- Size
- 345 KB
Daily fill level by dam
- Rows
- 86,619
- Period
- 23 October 2000 – 6 November 2026
- Size
- 3.5 MB
Citywide daily fill level (Parquet)
- Rows
- 8,894
- Period
- 23 October 2000 – 6 November 2026
- Size
- 187 KB
Daily fill level by dam (Parquet)
- Rows
- 86,619
- Period
- 23 October 2000 – 6 November 2026
- Size
- 761 KB
Hindcast results
- Rows
- 19,435
- Period
- 2 January 2010 – 30 December 2023
- Size
- 2.7 MB
Live forecast results
- Rows
- 2,618
- Period
- 19 October 2026 – 5 November 2026
- Size
- 586 KB
Every day’s forecast is kept.
Each day’s forecast is saved as one Parquet file and never changed. The archive holds 19 days so far (19 October 2026 – 6 November 2026).
- 2026-11-06.parquet (Forecast file for 6 November 2026)
- 2026-11-05.parquet (Forecast file for 5 November 2026)
- 2026-11-04.parquet (Forecast file for 4 November 2026)
- 2026-11-03.parquet (Forecast file for 3 November 2026)
- 2026-11-02.parquet (Forecast file for 2 November 2026)
- 2026-11-01.parquet (Forecast file for 1 November 2026)
- 2026-10-31.parquet (Forecast file for 31 October 2026)
- 2026-10-30.parquet (Forecast file for 30 October 2026)
- 2026-10-29.parquet (Forecast file for 29 October 2026)
- 2026-10-28.parquet (Forecast file for 28 October 2026)
- 2026-10-27.parquet (Forecast file for 27 October 2026)
- 2026-10-26.parquet (Forecast file for 26 October 2026)
- 2026-10-25.parquet (Forecast file for 25 October 2026)
- 2026-10-24.parquet (Forecast file for 24 October 2026)
Each file is named after its date: yyyy-mm-dd.parquet. The schema is below.
What the columns mean.
Citywide daily (city_daily)
| Column | Meaning |
|---|---|
| date | date in İstanbul time |
| fill_pct | citywide fill, percent of capacity |
| volume_hm3 | water in the dams, million m³ |
| source | which source the row comes from |
| method | reported (the source’s own figure) or sum_of_dams (the dams added up) |
| flag | short warning labels, empty if none |
Daily by dam (dam_daily)
| Column | Meaning |
|---|---|
| date | date in İstanbul time |
| dam_id | the dam’s short name |
| fill_frac | fill level as a fraction from 0 to 1 |
| volume_hm3 | water in the dam, million m³ (fill × the capacity in force on that date) |
| source | which source the row comes from |
| flag | short warning labels, empty if none |
Results (hindcast_scores, live_scores)
| Column | Meaning |
|---|---|
| issue_date / target_date / horizon_days | when the forecast was made, the day it was for, and how many days ahead |
| p10 / p50 / p90 | forecast fill, percent: the low end, middle and high end of the 80% range |
| actual / error / abs_error / covered | what happened and how the forecast did |
| model / model_version / scenario | which method made the forecast |
| kind | live or hindcast. The two are never in the same file |
Forecast archive
| Column | Meaning |
|---|---|
| issue_date / data_cutoff | the day the forecast was made and the day of the last reading it used |
| model / model_version / scenario / transfer_setting | which method made the forecast, with which assumptions |
| quantity / dead_storage | fill_pct (fill level) or reserve_days (days the water lasts), with the dead-storage reading |
| target_date / horizon_days | the day forecast and how many days after the issue date it is |
| p10 / p50 / p90 | the 80% range and its middle |
How we write the numbers.
- Volumes are in million m³ (hm³). Fill level is a 0–1 fraction per dam (fill_frac) and a percentage citywide (fill_pct).
- Dates are in İstanbul time.
- Every row says where its data came from (the source column). Unknown values are left empty and never filled with an estimate.
- Volumes are each dam’s fill percentage times the capacity in force on that date (see the Dams page). Per-dam volumes before and after 20 February 2024 can’t be compared.
- Hindcast and live results are in separate files.
The period with missing data.
There is no per-dam daily data between 20 February 2024 and 15 April 2026, only the summer-only DSİ series. The gap is permanent.
Terms of use.
The tables we combine and derive are shared under CC BY 4.0. Credit Su Ufku and the sources below when you use them. Each value is also subject to its own source’s licence.
Where the data comes from.
- İSKİ (primary source)
- Dam levels, capacities and transfer totals: iski.istanbul/baraj-doluluk.
- İBB Open Data Portal
- Daily dam fill, rainfall and consumption 2000–2024: data.ibb.gov.tr (İBB Open Data Licence).
- dolulukorani.com (secondary source)
- Daily fill level since 2026 and a capacity table (CC BY 4.0): dolulukorani.com. “Source: dolulukorani.com (compiled from official data)”.
- DSİ
- The summer-only State Hydraulic Works fill series, via dolulukorani.com.
- Open-Meteo
- ERA5 reanalysis and the ECMWF ensemble forecast (CC BY 4.0): open-meteo.com.
- OpenStreetMap
- Dam coordinates (ODbL): openstreetmap.org/copyright.
For the daily fill level you can also look at dolulukorani.com’s own pages.
Where these figures come from
- Latest reading
- Friday 6 November 2026, 00:00
- Source
- İSKİ
- Updated
- Friday 6 November 2026, 23:04
- Files
- data.json, home.json
- Model version
- 2