The Water Coverage KPI measures the percentage of a monitored site's total area that is occupied by water bodies — both inland (rivers, lakes, ponds, wetlands) and marine (coastal and saltwater). It is one of the land-cover sub-indicators derived from the multi-source CORINE Land Cover (CLC) classification pipeline that runs for every site.
Water bodies play a fundamental ecological role: they support aquatic and riparian biodiversity, regulate local microclimate through evaporative cooling, act as water purification infrastructure, and provide habitat for a wide range of species from macroinvertebrates to birds and amphibians. The proportion of a site covered by water is therefore both a direct habitat metric and a proxy for hydrological ecosystem services.
What it measures: For a given site polygon (ROI) and its paired control area (CA), the platform computes the percentage of total surface area covered by freshwater (inland water) and marine water (saltwater bodies), expressed as a single combined percentage. This is displayed alongside the control area value and a grade on the A–E scale.
Scale: This indicator is not inverted — higher values indicate more water coverage and are ecologically preferable (more habitat for aquatic species, better hydrological balance). A grade of A indicates 80% or more of the site is water-covered; grade E indicates less than 20%.
Water Coverage is derived from the NAA (Naturality Assessment Area) child layer of the CLC land cover map produced by the 3Bee multi-source machine learning pipeline. It combines inland water (rivers, lakes, ponds, wetlands) and marine/saltwater bodies into a single percentage.
where Inland Water = rivers, lakes, ponds, wetlands; Marine Water = coastal and saltwater bodies; Total Site Area = all hectares of the site including the water surface itself
Unlike the Natural Coverage indicator, the denominator includes ALL hectares of the site — including the water surface itself. This means a site that is 100% lake would show Water Coverage = 100%.
Data are sourced from the multi-source CLC classification pipeline using 10 input datasets at 10 m resolution, including ESA WorldCover, Sentinel-2 composites, CORINE Land Cover, and others.
Gauge. A semicircular gauge displaying the water coverage percentage for the site (ROI) relative to its control area (CA) on a 0–100% scale.
Purpose: To assess the fraction of the site's surface covered by water bodies and compare it to the surrounding landscape — answering "How much of my site is water?"
Description: The gauge shows two arcs: the outer arc for the Site (ROI) value, the inner arc for the Control Area (CA) value. The site arc is positioned on the colour-coded quality arc (A = teal at 12 o'clock, E = pink at left). A grade badge (A–E) appears alongside the ROI value. A delta badge below the gauge shows the difference (ROI − CA) as a signed percentage. The section heading reads "Water Coverage" with the ESRS tag "E3". The subtitle reads "Comparison of water body presence control-site."
12.4%Water Coverage
How it's calculated: Water Coverage % = (inland water hectares + marine water hectares) / total site hectares x 100. Grade thresholds: A ≥ 80%, B 60–80%, C 40–60%, D 20–40%, E < 20%.
Legend:
| Level | Range | Color | Meaning |
|---|---|---|---|
| A (Excellent) | ≥ 80% | ■ #00A67A | High water coverage — major wetland, lake, or riparian site |
| B (Good) | 60–80% | ■ #00DF80 | Majority water surface |
| C (Moderate) | 40–60% | ■ #FFD21E | Significant water presence |
| D (Poor) | 20–40% | ■ #FF8B16 | Limited water bodies |
| E (Critical) | 0–20% | ■ #FF367F | Little to no detectable water coverage |
Interpretation example:
If the gauge shows Site = 12.4% (grade E) and Control = 3.1%, the site has more water coverage than its surroundings — but both values fall in grade E, suggesting limited aquatic habitat. A positive delta (+9.3%) indicates the site is relatively water-richer than the landscape context.
Assessment Sidebar Row. A compact card in the Assessment highlights sidebar showing the site's freshwater status.
Purpose: To surface the freshwater sub-indicator at a glance on all Assessment pages, labelled by ESRS topic "E3 | Water".
Description: The card displays the label "Freshwater" with the topic badge "E3 | Water" above and a mini gauge arc or grade badge below. It appears in the Status & Impact sidebar alongside other environmental topic cards (Aridity, Hydrogeological, etc.).
How it's calculated: Derived from a secondary freshwater sub-indicator — the percentage of water bodies in the NAA analysis zone. Thresholds: A ≥ 60%, B 40–60%, C 20–40%, D 10–20%, E < 10%.
Interpretation example:
A card showing grade E for Freshwater means the site's analysis zone has less than 10% water coverage — low aquatic habitat presence for the surrounding landscape context.
Summary Dashboard. A panel in the right sidebar of the Maps > Land Use page that displays key land-use sub-indicators as KPI cards, including Water Coverage.
Purpose: To present all derived land-use metrics in one scannable panel alongside the interactive CLC map — enabling instant spatial context for each indicator.
Description: Six KPI cards appear in the panel: Natural Coverage, Impermeability, Water Coverage, Trees Density, Trees / Citizen, Green / Citizen. The Water Coverage card shows a grade badge (A–E), the numeric value as a percentage, and a "CA" sub-badge indicating the control area value. A toggle labeled "Water Coverage" in the layer bar switches the map highlight to the water coverage layer.
How it's calculated: Same as the Assessment > Land Use gauge — water coverage % from the CLC classification for the currently selected polygon (ROI or CA). Values update when the ROI/CA toggle changes.
Interpretation example:
If the panel shows Water Coverage E (0%), the site has no detectable water bodies under the current CLC classification — typical for dense urban or purely agricultural sites.
Highlights Card. A summary card in the Highlights section of Assessment pages, showing the site's freshwater coverage status at a glance.
Purpose: To surface the water coverage sub-indicator prominently in the highlights dashboard so users can quickly see whether the site has relevant aquatic habitat.
Description: The card displays the label "Freshwater" with a grade badge and status indicator. It is grouped under ESRS topic E3 alongside other water-related highlights (Aridity, Hydrogeological). This card appears on every assessment sub-page in the Status & Impact highlights section.
How it's calculated: Based on the freshwater sub-indicator (freshwater percentage within the NAA zone). Grade A ≥ 60%, B 40–60%, C 20–40%, D 10–20%, E < 10%.
Interpretation example:
A card showing grade A for Freshwater indicates that 60% or more of the analysis zone is covered by freshwater bodies — a site with exceptional aquatic habitat value, typical of wetlands, river floodplains, or lakeside areas.
Highlights Table Row. A row in the multi-site KPI comparison table within the Highlights section, enabling portfolio-wide comparison of water coverage.
Purpose: To allow users to compare water coverage across all monitored sites in a single table, alongside other land-use metrics.
Description: The column header reads "Water Coverage (SITE/CONTROL)" and shows the water coverage value for each site and its paired control area. Related columns include: Natural Habitat Coverage, Impermeable Land, Agricultural Coverage, Artificial Coverage.
How it's calculated: Same as the Assessment gauge — water coverage % from the CLC pipeline. Both Site and Control values are shown in the same cell as a SITE/CONTROL pair.
Interpretation example:
If one site shows 0%/13.9% and another shows 45%/8%, the second site has far more water coverage than its surroundings (delta +37%), while the first site has no water but its control area has moderate freshwater presence.
Gauge. The same gauge component as in Assessment > Land Use, displayed within the "Water" tab of the Risks page.
Purpose: To contextualise water coverage data within the broader water risk assessment, alongside aridity, soil impermeability, and tree density indicators.
Description: The gauge appears under the "Water" tab of the Risks page. It displays Site and Control arc values, a grade badge, and a delta, with the label "Water Coverage" and ESRS tag E3. The subtitle reads "Comparison of water body presence control-site."
12.4%Water Coverage
How it's calculated: Identical to the Assessment > Land Use version — water coverage % from the CLC pipeline.
Interpretation example:
If the Water tab shows Water Coverage E (0%) alongside Aridity grade D, it signals a site that is both water-scarce and drought-prone — a combined vulnerability flag for water-related risks.
Sites Progress Column. A column in the Scenarios multi-year comparison table, showing water coverage values across different scenario versions and years.
Purpose: To enable temporal and scenario-based comparison of water coverage, revealing whether changes in land use classification affect the detected water body presence.
Description: The column header reads "Water Cover". Rows show different site versions, years, and polygon configurations. Site and Control sub-columns display the raw percentage for each scenario.
How it's calculated: Same pipeline as all other water coverage values. Each scenario row reflects a different version of the CLC classification (different input vintage or polygon version).
Interpretation example:
If scenario V1 shows Water Cover 0.0% and V2 shows 2.1%, a small improvement in detection of water bodies occurred between versions — possibly due to improved input data coverage or polygon refinement.
| Source | Provider | Coverage | Resolution | Period |
|---|---|---|---|---|
| ESA WorldCover | ESA / Copernicus | Global | 10 m | 2020–2021 |
| Impact Observatory Annual LULC | Impact Observatory | Global | 10 m | 2017–2023 |
| CLC+ Backbone | Copernicus Land Monitoring | Europe | 10 m | 2018/2021 |
| CORINE Land Cover | Copernicus / EEA | Europe | Vector | 2018 |
| Sentinel-2 SCL Annual Composite | ESA / Copernicus | Global | 10 m | 2017–present |
| Google Dynamic World Annual Composite | Global | 10 m | 2017–present | |
| OpenStreetMap Roads | OpenStreetMap | Global | Vector | Continuous |
| European Dominant Leaf Type | Copernicus | Europe | 10 m | 2018 |
| European Crop Map | JRC | Europe | 10 m | 2018/2022 |
| Lombardy Forest Type | Regione Lombardia | Lombardy (IT) | Vector | 2023 |
Water Coverage is derived from the same multi-source CLC pipeline as Natural Coverage and Impermeability. It shares the same 10 input datasets and the same polygon-level aggregation logic. The pipeline combines multiple land cover products through a machine learning classification to produce a harmonized CLC map at 10 m resolution.
For each site polygon, the pipeline identifies pixels classified as inland water (rivers, lakes, ponds, wetlands) and marine/saltwater bodies. The total area of these water pixels is divided by the total site area to produce the percentage value. Unlike Natural Coverage, the denominator includes the water surface itself.
A secondary freshwater sub-indicator is also computed for the NAA (Naturality Assessment Area) zone with a different threshold scale (A ≥ 60%, B 40–60%, C 20–40%, D 10–20%, E < 10%), which drives the Freshwater Highlights card.