Recently scored: Severn Trent, United Utilities, South West Water, Scottish Water
Sector Rankings

Most Sustainable Water & Sewerage Companies 2026

11 Water & Sewerage companies ranked 0–100 on real environmental impact using SINK's open, physics-first formula.

11
Companies ranked
42
Sector average
50
Sector best (Severn Trent)
Full ranking
1
💧Severn TrentMaking progress
50
2
💧South West WaterMaking progress
49
3
💧United UtilitiesMaking progress
47
4
💧Scottish WaterMaking progress
46
5
💧Wessex WaterBelow expectations
43
6
💧Northumbrian WaterBelow expectations
42
7
💧Anglian WaterBelow expectations
41
8
💧Yorkshire WaterBelow expectations
39
9
💧Southern WaterBelow expectations
37
10
💧Dŵr Cymru Welsh WaterBelow expectations
37
11
💧Thames WaterBelow expectations
36
Frequently asked

Water & Sewerage sustainability, answered.

Which Water & Sewerage company is the most sustainable?

Severn Trent is the highest-scoring Water & Sewerage company on SINK with a score of 50/100 (Making progress).

What is the average sustainability score for Water & Sewerage companies?

The average SINK score across 11 Water & Sewerage companies is 42/100. The global average across all scored companies is 38/100.

How does SINK rate Water & Sewerage companies?

SINK scores Water & Sewerage companies on 10 questions using public data: Scope 1/2/3 carbon footprint, energy source, nature and biodiversity, resource use, water impact, emissions trajectory, science-based targets, transparency, and major controversies. The formula adjusts for the industry's inherent environmental footprint and company scale.

Which Water & Sewerage company has the worst sustainability score?

Thames Water has the lowest SINK score among Water & Sewerage companies at 36/100 (Below expectations).

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