Would you pay £300 million in response to a theoretical claim that freshwater mussels might suffer in a drought year? Well if you live in Cumbria you will soon have to make that payment. United Utilities are claiming that an EU directive to protect the freshwater mussels in the River Ehen means a massive pipeline has to be built across the Lakes from Thirlmere to supply all of West Cumbria's water. United Utilities are now (2020) building the UK's biggest integrated water supply pipeline through the heart of the Lake District.
Update 2023:United Utilities say of changes planned at Crummock/Ennerdale :There’s still a long way to go, and work is not expected to begin at the majority of sites until at least 2025/26. In the meantime, we’re continuing to carry out investigations and surveys.

The £300 million project, which may also alter the shorelines of both Crummock and Ennerdale lakes has been launched because of a perceived threat to the long term viability of around half a million freshwater mussels.
United Utilities wanted to build a 25 mile long pipeline to take water from Thirlmere reservoir, past Keswick and Bassenthwaite and out to West Cumbria.
North West water consumers will have to pay for the £300 million project to dig a water pipeline through the Lake District. The aqueduct is proposed to take water from Thirlmere all the way past Keswick to West Cumbria, even though Ennerdale & Crummock have been used as water supply for several decades.
And the reason for this huge expenditure? Beds of freshwater mussels in the River Ehen, which flows from Ennerdale. The freshwater mussels in the River Ehen, have been coping for the past few millennia with varying river levels, but the Environment Agency has declared the mussels in need of protection and now decided one of the main water supplies for West Cumbria (Ennerdale Lake) should close to make the mussels happier.
Similar mussel colonies in Northern Ireland and Scotland have also been described as 'under threat' by the same ecologists, yet these colonies are not associated with any reservoirs so the likely cause of any theoretical decline is some other factor. See Wikipedia for details of the existence of freshwater mussels across Europe and North America. Some of the research that claims the mussels are under threat.

As a consequence of the withdrawal of the Environment Agency licence to use Ennerdale Lake by 2020 United Utilities say they will have to lay a huge water pipeline all the way from Thirlmere to West Cumbria and build new treatment works near Cockermouth. They have also laid another pipeline to help the mussels in the near term by pumping water uphill from boreholes at Egremont to Ennerdale. This project has prompted a vigorous campaign from households hit by the changed supply.
A relatively new treatment works at Ennerdale will also be closed. The government called for a public inquiry into the water company plans and at Workington on September 16 and 17 2014 appointed inspector, Mr Stephen Roscoe to consider the plans. He cross examined the various experts on the proposals. He then (December 10 2014) waved the plans through despite the various concerns.
The hearing heard that the water company plans to stop using Crummock and Ennerdale lakes as water supplies. This will mean the weirs on both lakes would be removed and this could affect the shoreline on both lakes. The hearing also heard one of the ecological experts admit that the predictions of whether the mussel beds would benefit from the proposed changes were "not an exact science." The only glimmer of common sense from the planning process was that plans for a water desalination plant at Workington to convert seawater to drinking water was judged too expensive!
As the final planning application was approved by Allerdale Council (November 2016), residents are slowly waking up to the absurdity.
One objector from Papcastle rightly informed Allerdale that "The EU directive does not require or intend action based on a small theoretical risk, it has been misinterpreted. The most that could be required by a proper interpretation of the EU directive is a revision to the requirements for minimum flow in the River Ehen during a drought order to match the directive wording about overriding human need, while retaining the abstraction licence for use in normal circumstances or emergencies."
In the real world the million strong mussel colony has coped for centuries with drought and flood down the River Ehen.
There are other freshwater mussel populations in Northern Ireland and Scotland and there are approximately 900 species worldwide.
Similar mussel beds occur in the River Irt, in Scotland and in the Sperrin mountains of Northern Ireland.
Read of the Black Pearls once a Victorian jewel.
D.J.S.

In August 2017: These same mussels even seem to have their own Public Relations team working on their behalf. The Keswick based Pearls in Peril Project has issued glossy leaflets claiming in true tabloid headline style: "An iconic and vital species is at critical risk of extinction". This is despite the fact that freshwater mussels are endemic across Europe and North America, so quite what the extinction threat is remains a mystery.
Local MP and Facebook campaigns went viral after households forced to take hard water from boreholes as part of the absurd claims to help freshwater mussels. United Utilities spend ratepayers cash on laying pipeline for borehole water pumped uphill to Ennerdale treatment plant to add to normal Ennerdale water.

Detailed information on the United Utilities website.