Sempachersee
Sempachersee in Lucerne, Switzerland has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 3.9 m visibility.
- Clarity
- 3.9 m
Why Sempachersee has no A–F grade
Sempachersee in Switzerland 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, but not 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: 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. 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 Sempachersee
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 12.8 ft. Trophic State Index: 40.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 3.9 m | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 40 | Mesotrophic |
Moderate nutrients, good water quality
Where to stay near Sempachersee
Compare lakeside cabins, hotels, and vacation rentals near Sempachersee in Lucerne, Switzerland — 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 Sempachersee
Frequently asked questions about Sempachersee
What is the water quality of Sempachersee?
- Sempachersee in Lucerne, Switzerland has official water-quality measurements, not a LakeQuality A–F grade. 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.
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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 stored separately from LakeQuality A–F letters and are never blended. See how grades are calculated and data sources.