山中湖
山中湖 in Yamanashi, Japan has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.4 m visibility. Phosphorus: 10 µg/L.
- Clarity
- 4.4 m
Why 山中湖 has no A–F grade
山中湖 in Japan 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 and phosphorus, but not 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 Ministry of the Environment (Japan).
山中湖 is a lake in Yamanashi County, Japan.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2025-03-15. 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 山中湖
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Good clarity, visible to about 14.4 ft. Phosphorus level: 10 µg/L. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.4 m | Not graded |
| Phosphorus | 10 µg/L | Not graded |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near 山中湖
Compare lakeside cabins, hotels, and vacation rentals near 山中湖 in Yamanashi, Japan — 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 山中湖
Frequently asked questions about 山中湖
What is the water quality of 山中湖?
- 山中湖 in Yamanashi, Japan has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.4 m visibility. Phosphorus: 10 µg/L.
Is 山中湖 safe to swim in?
- 山中湖 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 山中湖 across LakeGrade
More lakes in Japan
Where this data comes from
44 measurements from 1 monitoring station, 2016–2025. Retrieved from Japan MOE public water-body monitoring (not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- Ministry of the Environment (Japan)
moe-jp44 samples · 2016–2025
Analytical methods
- MOE public water body monitoring (kosui, lakes)
Monitoring station identifiers (1)
1920010
Authority classifications are stored separately from LakeQuality A–F letters and are never blended. See methodology and data sources.
Data Sources
Water quality data from the EPA Water Quality Portal
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion
Most recent sample: 2025-03-15
Monitoring stations: 1