Situated in North East England, the River Tees Estuary is one of the most heavily modified and developed estuaries in the UK.
Since the mid-1800s, industries like mining and steel have been heavily concentrated along its banks. While crucial to the economy, this industrialisation has taken a devastating toll. Today, less than 10 percent of the estuary’s original intertidal habitat remains, causing a substantial decline of some species.
Partnering with the Environment Agency, we’re developing an outline business case for the North Tees Nature Park to revive these essential habitats.
This project is part of the Environment Agency’s £30 million Tees Tidelands programme, which aims to ‘realign, restore and reconnect intertidal habitats and species’.
Our role involves advising on the best approach to transform a steep slag bank on the estuary edge into a new intertidal terrace suitable for saltmarsh habitat.
Recreating intertidal habitats: a crucial part of the local ecosystem
Saltmarsh plays a vital role in the Tees Estuary ecosystem by filtering out pollutants from the water, providing nursery and refuge areas for bird and fish species, and supporting biodiversity. It can also strengthen flood resilience.
Despite being scarce around the UK, the Tees has one of the few patches of saltmarsh within the North East of England. Yet due to intense industrialisation, significant areas of it have been transformed into freshwater grazing marshes – making it difficult for certain species that depend on these habitats (such as wading birds) to survive.
The North Tees Nature Park seeks to address this problem by lowering the ground within the land boundary to reconnect it with the Tees’ natural tide cycles. This will not only enable once-abundant species to thrive again but will also create a healthier, safer estuarine environment.
Assessing contaminated land
Until the 1970s, the land that would have formed part of the natural estuary was reclaimed to build industrial sites – and soon became filled with slag (a by-product of smelting) and other wastes.
In 1970, Redcar Council reported that more than 500 tonnes of industrial waste was deposited into the River Tees each year. This is why conducting a thorough ground investigation to assess soil conditions and the composition of the material to be removed was crucial.
Spanning one kilometre long and 30 metres wide, the designated land sits next to the Augean Port Clarence landfill site and is currently owned by the Teesside Environmental Trust.
Given the likely contamination and high removal costs of slag waste, the Teesside Environmental Trust is exploring the possibility of selling the material for reuse. Therefore, we included specific testing in our ground investigation to see if this is feasible. If it is, it could significantly reduce project costs.
Creating a sustainable legacy for the Tees Estuary
To establish a baseline of the existing biodiversity, our specialists carried out terrestrial and intertidal habitat surveys.
Using this data, we can compare the current terrestrial biodiversity with the potential intertidal biodiversity gained by lowering the land.
We also studied the potential effects on water quality within the River Tees, as well as impacts on landscape, cultural heritage, archaeology, and local flora and fauna.
Once complete, the North Tees Nature Park will not only restore these critical habitats, creating a vibrant, biodiverse ecosystem, but it will also reconnect the Teesside communities with their estuary – a connection gradually lost over the past two centuries.