Hydrometric / Evidence atlas
The evidence, before the conclusion.
We test UK flood-hydrology methods at national scale, publish what survives, show what fails, and state exactly where the evidence stops.
UK hydrology in numbers
- adjacent same-river gauge pairs
- 85
- stations in the QMED revalidation
- 918
- basins in the finite-sample test
- 27
- catchments in the ReFH parameter refit
- 640
Featured publication
What National-Scale Analysis Reveals About UK Hydrology
What changes when UK flood-hydrology methods are examined across networks rather than one catchment at a time? Four bounded experiments show where gauge records disagree, where validation design changes a model comparison, where record length limits growth-curve targets, and where a temporal result must remain a case study.
Read the evidence- Status
- Current publication
- Version
- 1.0.0
- Evidence cut-off
Evidence library
Current publications
National hydrology
What National-Scale Analysis Reveals About UK Hydrology
A network-scale examination of gauge consistency, QMED validation, record-length limits and temporal sensitivity, with each result kept inside its evidential boundary.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
QMED
Can Machine Learning Improve QMED?
A fair national comparison showing why an ML accuracy claim failed under geographic validation, while open-input access, repeatability and auditability survived.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Statistical methods
The 2025 Statistical Method: What Changed and Why It Matters
A practitioner account of the FEH 2025 descriptor, QMED, donor, pooling, urban, distribution and uncertainty changes, with Hydrometric’s implementation evidence kept inside its local verification boundary.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Growth curves
Skew, Scale and the Shape of UK Flood Growth
A bounded account of index-flood scale, L-CV dispersion, L-skew shape, GF100 growth, a gauged-only rating result and one frozen finite-sample model failure.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Uncertainty
How Certain Is a Design Flood?
A layered account of population validation scatter, network inconsistency, within-record sampling and the still-open model-family protocol.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Rainfall-runoff modelling
From ReFH Design Events to Continuous Hydrology
A bounded record of the baseflow-lag refit, the public ReFH1 baseline gap, the failed daily two-store branch and the gated status of regional continuous evidence.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Flood estimation practice
The Modern Flood Estimation Report
A practical evidence-record model for study purpose, data review, method selection, uncertainty, provenance and approval, with an honest audit of the current Hydrometric generator.
- Status
- Current publication
- Version
- Version 1.0.0
- Evidence cut-off
- Evidence through
Publication standard
How we publish
Fair baselines. Information symmetry. Distributions, tails and failure fractions. Explicit retractions. No accuracy number without its boundary.
Fair baselines
Comparisons preserve information symmetry and use validation that matches the claim.
Distributions before headlines
Medians sit beside sample sizes, tails, subgroup behaviour and failure fractions.
Bounded conclusions
Every claim states what the experiment supports and where the evidence stops.
Visible corrections
Material changes create a new version; superseded and retracted evidence remains visible.
Living record
Recent revision ledger
- Version 1.0.0
What National-Scale Analysis Reveals About UK Hydrology
Initial publication of the national hydrology evidence synthesis.
- Version 1.0.0
Can Machine Learning Improve QMED?
Initial publication of the ML QMED adversarial revalidation.
- Version 1.0.0
The 2025 Statistical Method: What Changed and Why It Matters
Initial practitioner report on the FEH 2025 statistical method and bounded local implementation scope.
- Version 1.0.0
Skew, Scale and the Shape of UK Flood Growth
Initial publication separating scale, L-moment shape, growth, gauged rating evidence and finite-sample model failure.
- Version 1.0.0
How Certain Is a Design Flood?
Initial publication separating population validation, network consistency, finite-record sampling and proposed model-family sensitivity.
- Version 1.0.0
From ReFH Design Events to Continuous Hydrology
Initial publication of bounded ReFH parameter, baseline-gap, failed daily-branch and gated regional-continuous evidence.
Audit boundary
Source and disclosure principles
We disclose
Cohorts, validation design, baselines, distributions, important failure modes, limitations and traceable evidence identifiers.
We withhold
Deployable recipes, learned parameters, private data mechanics, customer information and licensed commercial outputs.
Stable current-report addresses begin with /research/; material revisions retain immutable versioned addresses.