H1 2026 Evaluation
Cambodia Reservoir Transparency
F2Opaque — Ranked #147 out of 167 countries
weight 30%
weight 20%
weight 15%
weight 13%
weight 10%
weight 8%
weight 5%
Primary source evaluated
Dimension breakdown
Data Availability
20% of total score
Coverage is 0 (no national reservoirs >10 hm³ with public data). Quality dimensions for the COVERED subset are therefore 0 by definition. Original notes preserved below: No Cambodian government agency publishes current reservoir storage volumes online. MOWRAM's website (mowram.gov.kh) contains zero data downloads; EDC (edc.com.kh) publishes no operational data for Kamchay, Stung Tatay, Stung Atay or Lower Sesan 2. The only publicly viewable water-level figure for Cambodia comes from the MRC Regional Flood Forecasting portal, which displays a rolling 7-day water-level reading at Prek Kdam (Tonle Sap River). This is a single gauge on the lake outflow, not a storage-volume metric, and it is from a regional body rather than the Cambodian state. All Chinese-built HPP operators (Sinohydro, PowerChina, Huaneng) publish no storage data.
Technical Accessibility
15% of total score
Coverage is 0 (no national reservoirs >10 hm³ with public data). Quality dimensions for the COVERED subset are therefore 0 by definition. Original notes preserved below: No Cambodian government data is accessible in any machine-readable format. MOWRAM collects real-time hydrological data via mobile networks and SUTRON software internally but does not expose any API or open-format download. The MRC Data Portal (the only regional source with Cambodia data) requires a formal license agreement and a fee for raw data download; the free tier only provides interactive visualisation of water levels. Open Development Cambodia's reservoir dataset is static GIS metadata from 2009-2010 in PDF/CSV, not operational data.
Coverage
30% of total score
v1.3.0 capacity-weighted: coverage = round(100 × covered_capacity_hm³ / total_national_capacity_hm³). Cambodia's total reservoir capacity above 10 hm³ is approximately 12,000 Mm³, dominated by Lower Sesan 2 (~5,600 Mm³ at FSL, ~47% of national capacity), Kamchay (~680 Mm³), Stung Tatay (~250 Mm³ inferred), Stung Atay (~200 Mm³), Atay-Russey Chrum, plus a few large irrigation impoundments. The Tonle Sap is a natural seasonal lake, excluded. MOWRAM operates 59 internal telemetry stations but publishes none publicly; Chinese-operated HPPs (Sinohydro/PowerChina/Huaneng) refuse to publish operational data. Covered capacity = 0 Mm³. Coverage = round(100 × 0 / 12,000) = 0.
Historical Depth
13% of total score
Coverage is 0 (no national reservoirs >10 hm³ with public data). Quality dimensions for the COVERED subset are therefore 0 by definition. Original notes preserved below: No Cambodian government source provides machine-readable historical reservoir storage series. Third-party satellite resources exist: DAHITI (TU Munich) hosts Tonle Sap water-level altimetry from ~1993 to present, derived from ERS, Envisat, Jason and Sentinel missions, free after registration. G-REALM (USDA) similarly covers Tonle Sap from the 1990s. MRC historical discharge/level records for Prek Kdam and Stung Treng exist back to 1910 in some archives, but raw download requires a paid license agreement. None of these are Cambodian government-published series on reservoir storage. Score reflects partial credit only for existence of accessible third-party altimetry heritage.
Update Frequency
10% of total score
Coverage is 0 (no national reservoirs >10 hm³ with public data). Quality dimensions for the COVERED subset are therefore 0 by definition. Original notes preserved below: MOWRAM has confirmed real-time internal telemetry from 59 operational stations using mobile networks, but none of this feeds any public-facing data stream. The MRC Prek Kdam page updates in near-real-time (daily readings), but this is a single river-gauge level for flood-forecasting, not a reservoir storage update from the Cambodian government. EDC and dam operators publish no operational data at any frequency. Calls for transparency from NGOs (Cambodianess, HRW, International Rivers) and academics have gone unheeded as of 2026.
Methodological Transparency
8% of total score
Coverage is 0 (no national reservoirs >10 hm³ with public data). Quality dimensions for the COVERED subset are therefore 0 by definition. Original notes preserved below: No Cambodian government authority has published documentation of measurement methodology, sensor calibration standards, or rating curves for any reservoir. MOWRAM's 2019 national water data roadmap acknowledged the need for a National Water Resources Data Management Centre but no public methodology documents have emerged by 2026. The MRC publishes technical documentation for its own monitoring network, including sensor specifications and data protocols, but this covers inter-governmental Mekong stations rather than national Cambodian reservoir management. Chinese dam operators (Sinohydro, PowerChina, Huaneng) have consistently refused to publish environmental and operational methodology in Cambodia.
Language and Usability
5% of total score
MOWRAM's website is effectively Khmer-only with no data content in any language. EDC's website has an English version but contains no data. The MRC Data Portal is in English and provides freely viewable water-level charts for Tonle Sap stations—this is the only Cambodia-relevant source with English-language accessibility. Satellite-derived third-party resources (DAHITI, G-REALM, Mekong Dam Monitor) are English-language and globally accessible but are not Cambodian government outputs. Partial credit is awarded because MRC English-language data is the de facto public-facing source for Cambodia.
Evaluator notes
Cambodia scores near the bottom of the RTI for a country with significant managed water storage. The national picture is shaped by two structural problems: institutional opacity and Chinese-contractor secrecy. MOWRAM operates 59 real-time telemetry stations and collects hydrological data continuously, but none of this feeds any public-facing portal; the ministry explicitly describes its data as supporting internal flood-forecasting rather than public transparency. All large HPPs — Kamchay (193 MW, ~680 Mm³), Stung Tatay (246 MW), Stung Atay (120 MW), and Lower Sesan 2 (400 MW, ~5,600 Mm³) — were built and are operated by Chinese state-owned firms under BOT contracts with EDC; these operators have no contractual or regulatory obligation to publish storage data, and consistently decline to do so. Civil society organisations, including Human Rights Watch, International Rivers and Cambodianess, have publicly called for transparency on reservoir operations and environmental impact assessments, without result. The only substantive public data on Cambodian water levels comes from two external sources: the MRC Regional Flood Forecasting portal (ffw.mrcmekong.org), which displays near-real-time gauge readings for the Prek Kdam station on the Tonle Sap outflow in English and without registration; and satellite altimetry services (DAHITI, G-REALM, Hydroweb) that provide Tonle Sap lake-level series going back to 1993. Neither constitutes a government reservoir-storage disclosure. The MRC Data Portal holds 10,000+ datasets including historical water-level series for Cambodia going back decades, but bulk download requires a formal license agreement and data fee, making it semi-restricted. Path to improvement is achievable but requires political will: MOWRAM's internal data infrastructure is technically functional, and regulatory amendments requiring HPP operators to report storage volumes to a public database would move Cambodia rapidly up the RTI scale. ADB has funded water data management studies and the 2019 National Water Resources Data Management Centre concept, but no operational public portal has materialised as of 2026.
Evaluated by Jaime Delgado · 2026-09-15 · Methodology v1.3.0