Serpentine Lake
Serpentine Lake in Herts and North London, England has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 260 µg/L. Chlorophyll-a (algae): 29 µg/L.
Why Serpentine Lake has no A–F grade
Serpentine Lake 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).
Serpentine Lake is a lake in Herts and North London County, England.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled 2026-07-28. Grade methodology: LakeGrade methodology.
Watch Serpentine Lake 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 Serpentine Lake
These readings exist but do not meet the evidence bar for an A–F grade — see why.
No clarity data. Phosphorus level: 260 µg/L. Chlorophyll-a: 29 µg/L. Trophic State Index: 74.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | 260 µg/L | Not graded |
| Chlorophyll-a (Algae) | 29 µg/L | Not graded |
| Trophic State Index (TSI) | 74 | Hypereutrophic |
Very high nutrients, dense algae, poor clarity
Where to stay near Serpentine Lake
Compare lakeside cabins, hotels, and vacation rentals near Serpentine Lake in Herts and North London, 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 Serpentine Lake
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Fishing Serpentine Lake
Frequently asked questions about Serpentine Lake
What is the water quality of Serpentine Lake?
- Serpentine Lake in Herts and North London, England has official water-quality measurements, not a LakeQuality A–F grade. Phosphorus: 260 µg/L. Chlorophyll-a (algae): 29 µg/L.
Is Serpentine Lake safe to swim in?
- Serpentine Lake 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 Serpentine Lake across LakeGrade
More lakes in England
Where this data comes from
115 measurements from 2 monitoring stations, 2022–2026. Retrieved from the Environment Agency (England; not the EPA Water Quality Portal) on 2026-08-16.
Collected and reported by
- Environment Agency (England)
ea-wqa115 samples · 2022–2026
Monitoring station identifiers (2)
TH-PGWL0215TH-PGWL0217
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: 2026-07-28
Monitoring stations: 2