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LakeQuality

Cow Green Reservoir

Northumberland Durham and Tees, EnglandView mapDirections

EA publishes the water-quality measurements for Cow Green Reservoir. Here is what has been measured.

Phosphorus
9.2 µg/L
Less phosphorus than most
Measured by EA
Chlorophyll-a
1 µg/L
Less algae than most
Measured by EA
  • Limited data

Cow Green Reservoir in Northumberland Durham and Tees, England has official water-quality measurements, shown as reported. Phosphorus: 9.2 µg/L. Chlorophyll-a (algae): 1 µg/L.

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How Cow Green Reservoir is classified

Cow Green Reservoir in England is published with the authority's own measurements and class. The measurements here are published by the agency that samples the lake, as reported. Sampling here has recorded phosphorus and algae (chlorophyll-a), but not water clarity.

LakeQuality publishes no grade of its own beside it. Everything below thathas been measured is reported on this page.

Monitoring: the Environment Agency (England).

Cow Green Reservoir is a lake in Northumberland Durham and Tees County, England.

Source: the Environment Agency (England) — not the EPA Water Quality Portal, last sampled 2020-01-17. Methodology: how these readings are compared.

Swimming conditions

No reading

Limited data

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether Cow Green Reservoir is safe to swim in today is a call for the Environment Agency (England) and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Cow Green Reservoir

These are the measurements EA publishes for Cow Green Reservoir. More on the source.

No clarity data. Phosphorus 9.2 µg/L. Chlorophyll-a 1 µg/L. TSI 34.

Water quality readings
MeasureReadingWhere it sits
Water clarity (Secchi depth)No reading

How deep a black-and-white disk stays visible from the surface. Higher is clearer.

Total phosphorus9.2µg/LMeasured, not scored

The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential.

Chlorophyll-a (algae)1µg/LMeasured, not scored

The green pigment in algae — a direct measure of how much algae is in the water.

Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a.34Oligotrophic
OligotrophicMesotrophicEutrophicHypereutrophic

Low nutrients, clear water. No reading is a swimming clearance.

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Answers come straight from the public measurements and survey records on this page.

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Fishing Cow Green Reservoir

Frequently asked questions about Cow Green Reservoir

Where is Cow Green Reservoir?

Cow Green Reservoir is a lake in Northumberland Durham and Tees, England. This page reports official water-quality measurements, shown as reported.

What is the water quality of Cow Green Reservoir?

Cow Green Reservoir in Northumberland Durham and Tees, England has official water-quality measurements, shown as reported. Phosphorus: 9.2 µg/L. Chlorophyll-a (algae): 1 µg/L.

Measurements on this page ↑

Is Cow Green Reservoir safe to swim in?

Cow Green Reservoir 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.

Swimming on this page ↑

Where this data comes from

73 measurements from 1 monitoring station, 2016–2020. Retrieved from the Environment Agency (England; not the EPA Water Quality Portal) on 2026-08-16.

Collected and reported by

  • Environment Agency (England)ea-wqa73 samples · 2016–2020
Monitoring station identifiers (1)
  • NE-45100054

Authority classifications are shown as the authority published them. See where the data comes from and data sources.