The Environment Agency data portal allows access to water quality date from around the UK:

EA Water Quality Archive

A number of areas are sampled roughly monthly on the River Tees, you can find them all on the data portal.

Sampling points around the downstream Tees

Below are a number of key ones:

• Dabholme Gut Confluence
• Tees At Redcar Jetty (Surface)
• Tees At The Gares (Surface)
• Tees At Smiths Dock (Surface)
• Tees At Teesport (Bottom)
• Tees At Teesport (Surface)
• Tees Coastal Inshore Of Teeside Windfarm
• Tees At Transporter Bridge (Surface)
• Seaton Channel East Of Dock 7
• Tees Bay Off Hartlepool Ps Main Cw Outfl
• Tees Between Seaton Channel & Bran Sands
• Tees At Haverton Hill Shipyard (Surface)
• Tees At Billingham Reach (Surface)

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</iframe><p><a href=“umap.openstreetmap.fr/en/map/river-tees-water-quality_910752”>See full screen</a></p> {/html} How does this compare to other places in the country? *LANGSTONE HARBOUR MOUTH SAMPLING POINT Make Tees data look very gappy? Why? However, *THAMES AT CHAPMAN BUOY (62.5KMS BELOW LONDON BRIDGE) seems to have the same gaps as Tees. Why? But other data doesn't have the same gaps: *THAMES AT MUCKING (53.2KMS BELOW LONDON BRIDGE) *THAMES AT OVENS BUOY (47.7KMS BELOW LONDON BRIDGE) *THAMES AT ERITH (26.6KMS BELOW LONDON BRIDGE)