Posted on September 8, 2022
Argument over where material dredged from the River Tees will be stored has rumbled on amid worry over crustacean deaths.
Teesworks has commissioned dredging near the new £107m South Bank Quay development with officials announcing its start last week. The channel is being deepened and dredged to a depth between 11m and 15m.
But continued crustacean and wildlife deaths – and its devastating impacts on the fishing industry – have prompted repeated questions over the cause. Defra ruled out dredging as a likely cause in its investigations published in May.
An algal bloom was deemed as “of significance” however, the report found no single, consistent causative factor was identified for the deaths. High levels of the chemical pyridine were found in dead creatures in another independent study by expert Tim Deere-Jones.
But a joint Defra led investigation “could not support the hypothesis that pyridine was the cause of the mortalities”. The terms set out by the Marine Management Organisation (MMO) stipulate what can be dredged on the river as part of the South Bank quay development.
Material dragged up between four co-ordinates has been excluded from disposal at sea, with an “enclosed bucket” to be used. The reason given was: “To prevent contaminated material being disposed of at sea or mobilised causing toxic or harmful effects to sensitive receptors.”
Hundreds of pages in the licence granted by the MMO detail what can go where. Last week, a Teesworks spokesperson said: “We will be dredging circa one million m³ next year in a second dredge as per and in accordance with our MMO Licence which is in the public domain.
“This licence followed a rigorous process, involving an extensive consultation with statutory bodies such as the Environment Agency, CEFAS, Natural England which has taken nearly 18 months. This current dredge… is being undertaken using enclosed bucket dredging, which will see the 125,000m³ of dredged material from the river and taken ashore.
“Next year, around one million m³ of material will be dredged from the Tees and disposed of at sea in the approved disposal location, in accordance with our MMO Licence.” On Friday, Middlesbrough MP Andy McDonald shared concerns about the “small proportion” of the excavation due to be stored on land compared to that to be dumped at sea.
This week, the Labour MP said questions were still outstanding about the cause of the ecological disaster. He added: “Experts, independent of government, have dismissed the official line repeated by the Environment Minister George Eustice in the House of Commons that the cause is algal bloom and it seems to me that they discount that theory with some considerable justification.
“The lack of official urgency or curiosity about this is staggering. Added to which, the levels of the chemical pyridine found in the dead creatures are off the scale.
“In any event, legitimate concerns remain as to whether there has been enough attention paid to this and Teessiders know their river. They know what has gone on its banks for the last 200 years and the stories abound from those who worked in various industries, as to how the river was used as a waste disposal facility over decades and decades with all manner of poisons being dumped in it.”
In response to a Tweet questioning what was going to sea and staying on land, Teesworks said the dredge where material was due to be disposed of at sea was next year. Tees Valley Mayor Ben Houchen criticised Labour in the aftermath.
MMO documents show a maximum amount of 902,000 cubic metres of dredged material is expected in “phase one” of work – with 187,000 cubic metres from the Tees Dock turning circle and 715,000 cubic metres from the channel and berth pocket of the river.
A Q&A document was released by Teesworks officials late last week on the back of the questions sparked by dredging for the quay beginning. When it came to the “contaminated portion of the dredge”, officials say the toxins found at one borehole during testing were cadmium, chromium, copper, mercury, lead, and zinc exceeded the respective Cefas action level 2 (AL2) thresholds.
This meant the material couldn’t be disposed of at sea. They also said “no other toxins were identified or exceeded mandatory thresholds”. Mr Houchen released a statement over the weekend pointing to how millions of tonnes of material was dredged from the Tees every year, and had been for decades.
He added: “Before starting this process we went above and beyond what is legally required for this type of development. We’ve worked closely with the Environment Agency, the Marine Maritime Organisation and other bodies responsible for regulation of rivers across the country and we’ve done everything required of us, and more, by these organisations before starting work.
“I’m proud to hold Teesworks to the highest standard and everything that is part of this dredge over the next eight weeks will be removed from the river entirely and without exception. It will be processed on land and disposed of on land.
“Not a single bit of this dredge will be disposed of at sea and the whole process is being overseen by Royal Haskoning who are the leading experts globally when it comes to the construction of new quays.”
The Tory mayor said he knew there were people with “genuine concerns” about the crustacean die off – and insisted the full documentation and licences were available to see.
He added: “I will continue to fight for support for our fishermen who must be given financial support given what occurred last year.” Material from this part of the eight week dredge is expected to go to landfill on the wider Teesworks site.