Where is Réservoir de Castelnau Magnoac?

Réservoir de Castelnau Magnoac is a lake in Hautes-Pyrénées, France. This page reports official water-quality measurements, shown as reported.

Is Réservoir de Castelnau Magnoac safe to swim in?

Réservoir de Castelnau Magnoac 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.

Réservoir de Castelnau Magnoac

Hautes-Pyrénées, FranceView map Directions

Eau France publishes the water-quality measurements for Réservoir de Castelnau Magnoac. Here is what has been measured.

Clarity

3.2 m

Clearer than most

Secchi · sampled 2024

Phosphorus

10 µg/L

Less phosphorus than most

Measured by Eau France

Chlorophyll-a

3 µg/L

Typical for France

Measured by Eau France

Limited data

See the measurements Directions Where to stay

Réservoir de Castelnau Magnoac in Hautes-Pyrénées, France has official water-quality measurements, shown as reported. Water clarity: 3.2 m visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3 µg/L.

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How Réservoir de Castelnau Magnoac is classified

Réservoir de Castelnau Magnoac in France is published with the authority's own measurements and class. The measurements here are published by the agency that samples the lake, as reported. Sampling here has recorded water clarity, phosphorus and algae (chlorophyll-a).

LakeQuality publishes no grade of its own beside it. Everything below thathas been measured is reported on this page.

Monitoring: the French water agencies, via UNEP GEMS/Water.

Réservoir de Castelnau Magnoac is a lake in Hautes-Pyrénées County, France.

Source: the French water agencies, via UNEP GEMS/Water — not the EPA Water Quality Portal, last sampled 2024-09-30. Methodology: how these readings are compared.

What Réservoir de Castelnau Magnoac is good for

From access and monitoring records, not editorial picks.

Clear water10.5 ft of visibility

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Réservoir de Castelnau Magnoac is safe to swim in today is a call for the French water agencies, via UNEP GEMS/Water and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Réservoir de Castelnau Magnoac

These are the measurements Eau France publishes for Réservoir de Castelnau Magnoac. More on the source.

Good clarity, visible to about 10.5 ft. Phosphorus 10 µg/L. Chlorophyll-a 3 µg/L. TSI 41.

Water quality readings
Measure	Reading	Where it sits
Water clarity (Secchi depth)	3.22m	Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer.
Total phosphorus	10µg/L	Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.
Chlorophyll-a (algae)	3µg/L	Measured, not scored The green pigment in algae — a direct measure of how much algae is in the water.
Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.	41	Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic

Moderate nutrients, good water quality

Ask about Réservoir de Castelnau Magnoac

Answers come straight from the public measurements and survey records on this page.

Stays via Stay22

Stays near Réservoir de Castelnau Magnoac

Compare lakeside cabins, hotels, and vacation rentals near Réservoir de Castelnau Magnoac in Hautes-Pyrénées, 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 Réservoir de Castelnau Magnoac

→ Réservoir de Castelnau Magnoac fishing regulations (limits, seasons, special rules)

Frequently asked questions about Réservoir de Castelnau Magnoac

Where is Réservoir de Castelnau Magnoac?: Réservoir de Castelnau Magnoac is a lake in Hautes-Pyrénées, France. This page reports official water-quality measurements, shown as reported.
What is the water quality of Réservoir de Castelnau Magnoac?: Réservoir de Castelnau Magnoac in Hautes-Pyrénées, France has official water-quality measurements, shown as reported. Water clarity: 3.2 m visibility. Phosphorus: 10 µg/L. Chlorophyll-a (algae): 3 µg/L.
Is Réservoir de Castelnau Magnoac safe to swim in?: Réservoir de Castelnau Magnoac 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.

Explore Réservoir de Castelnau Magnoac across LakeQuality

Lake Fishing Forecast

Species activity outlook by water temperature and season

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EU bathing ratings and named-lake measurements

Where this data comes from

77 measurements from 1 monitoring station, 2016–2024. 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-fr77 samples · —

Analytical methods

Hub'Eau / Naïades plans d'eau

Monitoring station identifiers (1)

O6215553

Authority classifications are shown as the authority published them. See where the data comes from and data sources.