Rostherne Mere
Rostherne Mere in Gtr Mancs Mersey and Ches, England has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 130 µg/L. Chlorophyll-a (algae): 9.9 µg/L.
Why Rostherne Mere has no A–F grade
Rostherne Mere in England 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 phosphorus and algae (chlorophyll-a), but not water clarity.
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 Environment Agency (England).
Rostherne Mere is a lake in Gtr Mancs Mersey and Ches County, England.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2026-05-11. Grade methodology: LakeGrade methodology.
Watch Rostherne Mere water quality
Subscribe for LakeQuality updates by email. No spam, unsubscribe anytime.
Swimming Safety
Not ratedLimited data
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Rostherne Mere
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data. Phosphorus level: 130 µg/L. Chlorophyll-a: 9.9 µg/L. Trophic State Index: 64.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 130 µg/L | Not graded |
| Chlorophyll-a (Algae) | 9.9 µg/L | Not graded |
| Trophic State Index (TSI) | 64 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Where to stay near Rostherne Mere
Compare lakeside cabins, hotels, and vacation rentals near Rostherne Mere in Gtr Mancs Mersey and Ches, England — 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.
Top-rated places to stay near Rostherne Mere
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Fishing Rostherne Mere
Frequently asked questions about Rostherne Mere
What is the water quality of Rostherne Mere?
- Rostherne Mere in Gtr Mancs Mersey and Ches, England has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 130 µg/L. Chlorophyll-a (algae): 9.9 µg/L.
Is Rostherne Mere safe to swim in?
- Rostherne Mere 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 Rostherne Mere across LakeGrade
More lakes in England
Where this data comes from
98 measurements from 1 monitoring station, 2019–2026. Retrieved from the Environment Agency (England; not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- Environment Agency (England)
ea-wqa98 samples · 2019–2026
Monitoring station identifiers (1)
NW-88022930
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: 2026-05-11
Monitoring stations: 1