Complexe de Mervent
Complexe de Mervent in Vendée, France has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 1.6 m visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 8.2 µg/L.
- Clarity
- 1.6 m
Why Complexe de Mervent has no A–F grade
Complexe de Mervent in France is published with the authority's own measurements, not a LakeQuality letter. official authority class; not a LakeQuality A–F letter Sampling here has recorded water clarity, phosphorus and algae (chlorophyll-a).
A letter on the LakeQuality scale would be an invention, not an official class. Everything below that has been measured is still reported on this page.
Monitoring: the French water agencies, via UNEP GEMS/Water.
Complexe de Mervent is a lake in Vendée County, France.
Source: the French water agencies, via UNEP GEMS/Water — not the EPA Water Quality Portal, last sampled 2025-09-30. Grade methodology: LakeGrade methodology.
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Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Complexe de Mervent
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Murky, only visible to about 5.2 ft. Phosphorus level: 20 µg/L. Chlorophyll-a: 8.2 µg/L. Trophic State Index: 51.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 1.6 m | Not graded |
| Phosphorus | 20 µg/L | Not graded |
| Chlorophyll-a (Algae) | 8.2 µg/L | Not graded |
| Trophic State Index (TSI) | 51 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Complexe de Mervent
Compare lakeside cabins, hotels, and vacation rentals near Complexe de Mervent in Vendée, France — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
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Fishing Complexe de Mervent
Frequently asked questions about Complexe de Mervent
What is the water quality of Complexe de Mervent?
- Complexe de Mervent in Vendée, France has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 1.6 m visibility. Phosphorus: 20 µg/L. Chlorophyll-a (algae): 8.2 µg/L.
Is Complexe de Mervent safe to swim in?
- Complexe de Mervent has official nutrient and clarity measurements, not a bacteria swim class and not a safety clearance. Algal blooms, currents, and depth are not covered. Always check local notices before swimming.
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Where this data comes from
39 measurements from 1 monitoring station, 2016–2025. Retrieved from UNEP GEMS/Water GFQA (not the EPA Water Quality Portal) on 2026-08-20.
Collected and reported by
- Office français de la biodiversité (Hub'Eau)
hubeau-fr39 samples · —
Analytical methods
- Hub'Eau / Naïades plans d'eau
Monitoring station identifiers (1)
N71-410
Authority classifications are stored separately from LakeQuality A–F letters and are never blended. See how grades are calculated and data sources.