Decision Dossier — Climate-Risk Requirements in Hydropower Studies
An evidence-led comparison of disclosure, pilot and mandate options for climate and hazard analysis in hydropower studies; the current corpus does not support a universal Q-design decrement or a claimed published national guideline.
- Page status
- Working page
- Updated
- 2026-07-19
- Last reviewed
- 2026-11-04
- Review due
- 2027-02-04
Decision Question
What climate-risk, hydrological-sensitivity and hazard information should DoED require in hydropower studies, and should any requirement begin as disclosure, a pilot standard or an immediate mandate?
Established Facts
- DoED Licensing Directive 2075 — Hydropower Project Licensing records a Q45 design-discharge requirement in the current amended licensing directive and states that the directive does not mandate climate-adjusted hydrology. It does not show how individual applicants implement the rule.
- WECS River Basin Plans and Hydropower Development Master Plan (2024) documents strong wet–dry seasonality using model-derived basin flows and warns that those values can differ from gauges and project studies.
- ICIMOD HKH Glacier Change Summary provides regional evidence of glacier loss and scenario-dependent long-term change. Its regional aggregates cannot be converted directly into a project-specific design-discharge factor.
- AIIB Dudhkoshi Storage Hydroelectric Project Summary (2026) identifies GLOF, sediment, slope stability, seismic and dam-safety risks for a proposed large storage project and says assessment instruments remain under preparation or review. This establishes the relevance of multi-hazard assessment, not a completed national standard.
- The current source corpus does not establish the publication and formal adoption of a final ICIMOD climate-resilient hydropower guideline. It also does not provide a census of modelling methods used in domestic feasibility studies.
Unknowns
- Which climate, hydrology and hazard methods recent project studies actually use, by basin, project size and financing source.
- Whether DoED is preparing a revised study guideline, the draft text, or an implementation timetable.
- The sensitivity of project economics and safety outcomes to specific hydrology datasets, scenarios and bias-correction methods.
- The staff, data and modelling capability available to DoED and domestic developers.
- The cost and delay associated with different study requirements.
- Whether a size threshold is appropriate; small projects can face serious local hazard exposure even when modelling budgets are limited.
Comparable Cases
The current corpus provides project-specific context rather than a comparable national regulation. Dudhkoshi's lender record identifies a broad hazard set; UAHEL Upper Arun Hydroelectric Project Page records current project parameters and preparation status but does not, on its own, establish a climate-adjusted method.
Transfer limitations: large projects with multilateral financing have different budgets, safeguard processes and review capacity from domestically financed projects. Project-specific assessment does not prove that the same method, scenario or cost is appropriate as a universal licensing rule.
Response Options and Trade-offs
| Option | What it would involve | Potential advantage | Material limitation or risk |
|---|---|---|---|
| Standard disclosure and sensitivity tests | Require every study to identify data periods, stationarity assumptions, climate scenarios, uncertainty ranges and hazard screens | Makes assumptions comparable without imposing one model result | Disclosure can become procedural unless DoED can review quality and require revisions |
| Pilot a technical standard | Apply a draft method to selected basins or project types and publish lessons | Tests data, cost and review capacity before scaling | Pilot projects may not represent Nepal's full basin and project diversity |
| Phase requirements by risk | Begin with larger or higher-hazard projects, then expand after capacity review | Focuses early effort where consequences may be larger | Size is an imperfect proxy for local hazard and can leave smaller projects under-screened |
| Immediate universal decrement factor | Apply one forward-looking reduction to design discharge across projects | Simple to administer and easy to compare | Creates false precision, can misstate basin-specific conditions and may shift rather than reduce risk |
| Retain current rules | Continue Q45 licensing without additional climate disclosure | Avoids new compliance cost and review burden | Leaves assumptions and climate-risk treatment difficult to compare or audit |
TransparentGov Assessment
Preferred evidence-led sequence: require transparent data, uncertainty and hazard disclosure; then pilot a reviewable technical standard before deciding whether any method should become mandatory. A fixed national decrement should not be adopted without basin-specific validation and an implementation-capacity assessment.
The assessment would change if DoED publishes an adopted method with technical annexes, consultation evidence and an implementation plan, or if a representative project-study review establishes a consistent, material gap that a specific standard can correct.
Monitoring Triggers
- A final DoED or ICIMOD hydropower study guideline with a stable official record.
- A DoED circular, amendment or consultation on climate-risk requirements.
- A representative review of feasibility-study methods by project size and financing source.
- Public project sensitivity tests connecting climate assumptions to design and financial outcomes.
- Evidence on compliance cost and regulator review capacity.