Sempachersee
Lucerne, SwitzerlandView mapDirections
Eawag publishes the water-quality measurements for Sempachersee. Here is what has been measured.
- Limited data
Sempachersee in Lucerne, Switzerland has official water-quality measurements, shown as reported. Water clarity: 3.9 m visibility.
How Sempachersee is classified
Sempachersee in Switzerland 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, but not 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: Eawag (the Swiss Federal Institute of Aquatic Science and Technology) and cantonal lake-monitoring programmes.
Sempachersee is a lake in Lucerne County, Switzerland.
Source: Eawag (the Swiss Federal Institute of Aquatic Science and Technology) and cantonal lake-monitoring programmes — not the EPA Water Quality Portal, last sampled 2023-11-13. Methodology: how these readings are compared.
What Sempachersee is good for
From access and monitoring records, not editorial picks.
- Clear water12.8 ft of visibility
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Sempachersee is safe to swim in today is a call for Eawag (the Swiss Federal Institute of Aquatic Science and Technology) and cantonal lake-monitoring programmes and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Sempachersee
These are the measurements Eawag publishes for Sempachersee. More on the source.
Good clarity, visible to about 12.8 ft. TSI 40.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.9m | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | No reading The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. | |
| Chlorophyll-a (algae) | No reading 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. | 40 | Mesotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Moderate nutrients, good water quality
Ask about Sempachersee
Answers come straight from the public measurements and survey records on this page.
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Fishing Sempachersee
Frequently asked questions about Sempachersee
Where is Sempachersee?
- Sempachersee is a lake in Lucerne, Switzerland. This page reports official water-quality measurements, shown as reported.
What is the water quality of Sempachersee?
- Sempachersee in Lucerne, Switzerland has official water-quality measurements, shown as reported. Water clarity: 3.9 m visibility.
Is Sempachersee safe to swim in?
- Sempachersee 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 Sempachersee across LakeQuality
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Where this data comes from
60 measurements from 1 monitoring station, 2016–2023. Retrieved from the listed programme (not the EPA Water Quality Portal). See data sources on 2026-08-20.
Collected and reported by
- Eawag
eawag-ch60 samples · —
Analytical methods
- Eawag long-term Swiss lake monitoring
Monitoring station identifiers (1)
LakeSempach
Authority classifications are shown as the authority published them. See where the data comes from and data sources.