Lake St Clair
Lake St Clair in NSW, Australia has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.8 m visibility. Chlorophyll-a (algae): 2.3 µg/L.
- Clarity
- 4.8 m
Why Lake St Clair has no A–F grade
Lake St Clair in Australia 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 algae (chlorophyll-a), but not phosphorus.
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: CSIRO (Commonwealth Scientific and Industrial Research Organisation).
Lake St Clair is a lake in NSW County, Australia.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2016-03-03. 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 Lake St Clair
These readings exist but do not meet the evidence bar for an A–F grade — see why.
Crystal clear, you can see 15.6 ft down. Chlorophyll-a: 2.3 µg/L. Trophic State Index: 38.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.75 m | Not graded |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | 2.3 µg/L | Not graded |
| Trophic State Index (TSI) | 38 | Oligotrophic |
Low nutrients, clear water, excellent for swimming
Where to stay near Lake St Clair
Compare lakeside cabins, hotels, and vacation rentals near Lake St Clair in NSW, Australia — 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 Lake St Clair
Frequently asked questions about Lake St Clair
What is the water quality of Lake St Clair?
- Lake St Clair in NSW, Australia has official water-quality measurements, not a LakeQuality A–F grade. Water clarity: 4.8 m visibility. Chlorophyll-a (algae): 2.3 µg/L.
Is Lake St Clair safe to swim in?
- Lake St Clair 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
14 measurements from 7 monitoring stations, 2016. Retrieved from CSIRO inland waters bio-optical sampling (not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- CSIRO
csiro-inland-biooptical14 samples · 2016
Analytical methods
- CSIRO inland waters bio-optical (surface HPLC chlorophyll-a, Secchi)
Monitoring station identifiers (7)
LS_01LS_02LS_03LS_04LS_05LS_06LS_07
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: 2016-03-03
Monitoring stations: 7