Cuba Reservoir Transparency

INRH publishes monthly hydrological bulletins (Boletín Hidrológico) in PDF format on hidro.gob.cu, reporting aggregate national fill percentages in hm³ and % of total capacity, with some provincial and regional breakdowns. Ad-hoc press releases via state media (Granma, ACN) occasionally name individual reservoirs with fill percentages. The website's 'Mapas' section includes a 'Porciento de llenado' (fill percentage) map. However, there is no structured open data portal, no downloadable dataset, and individual reservoir-level data is rarely published systematically. The ONEI annual statistical yearbook includes aggregate hydraulic infrastructure data. Data exists but is heavily fragmented, locked in PDFs, and not routinely disaggregated to reservoir level.

All published data is in PDF format only. The website's fill percentage map is a non-interactive image with no download capability. There is no REST API, no CSV or JSON endpoint, and no structured database. No registration is required to access the website, but the absence of any machine-readable format makes programmatic access impossible. An exhaustive search of Cuban government REST API inventories (including kenriortega/servicios-api-cuba) confirmed no water resource API exists. The website runs on Drupal but exposes no data feeds.

Methodology v1.3.0 (capacity-weighted) with conservative estimation applied 2026-05-29. Cuba's total national reservoir capacity is approximately 9,128 hm³ across 242 large reservoirs administered by INRH (plus 700+ micro-dams below threshold). The 20 largest reservoirs above 100 hm³ — Zaza (1,020 hm³), Hanabanilla (286 hm³), Alacranes, Mayarí, etc. — represent the bulk of capacity. INRH publishes monthly hydrological bulletins (Boletín Hidrológico) reporting aggregate national fill percentage with regional/provincial breakdowns and a 'Porciento de llenado' fill-percentage map. Covered capacity via aggregate INRH bulletins is approximately 5,475 hm³ on a conservative basis. Coverage = round(100 × 5,475 / 9,128) = 60. The conservative downward revision from 70 reflects that INRH publishes aggregate fill statistics rather than per-reservoir disclosure, that individual reservoir data appears only sporadically through press releases during drought events, and that smaller individual reservoirs below the top tier remain absent from any continuous public reporting.

The INRH publications page year filter extends back to 2001, suggesting monthly bulletins may span roughly 25 years. However, older bulletins are not readily accessible online — only isolated PDFs from 2018 and 2021 are confirmed accessible. ONEI yearbooks provide annual aggregate snapshots. Academic literature draws on baseline data from 1961–1990 but this is not publicly downloadable. No machine-readable historical time series for reservoir storage is publicly available. Historical depth exists institutionally but is not accessible to the public in usable form.

Monthly hydrological bulletins are confirmed, with the most recent on the publications page being April 2025. The 'Mapas' section of hidro.gob.cu includes a daily rainfall map, suggesting some data infrastructure is updated daily, though not public reservoir storage. Press releases with aggregate fill figures appear several times per year around drought events. The update cadence (monthly PDF) is regular but slow by international standards; no weekly or real-time data is publicly accessible.

INRH's legal mandate includes operating hydrometric monitoring networks, but no public methodology document describing measurement standards for reservoir storage (gauge types, survey methods, volume-area curves) was found. Cuba operates a network of 630 precipitation stations and has installed 184 modern hydrological stations in southern municipalities (2025, Mi Costa / Green Climate Fund project), but station specifications and measurement protocols are not publicly available. A 2025 CUJAE-INRH satellite innovation monitors reservoir surface area via Landsat, addressing SDG 6.6.1, but the methodology is described only in award materials rather than published technical standards.

The INRH website has a partial English version (hidro.gob.cu/en) covering institutional pages (mission, structure, directory) but no hydrological bulletins, maps, or data sections are available in English. All bulletins, press releases, and statistical publications are exclusively in Spanish. The ONEI yearbook is Spanish-only. Cuba's status as a closed state-controlled information environment means no independent third-party English-language portal mirrors official data. International accessibility is further limited by restricted internet connectivity within Cuba, reducing even Spanish-language reach.