The representation and supporting documents detail NEMRG’s key recommendations for essential restrictions to be imposed on the River Tees maintenance dredging licence renewal (MLA-2025-00263), alongside errors identified within the accompanying licence renewal documents.

These points are drawn directly from NEMRG's detailed analysis to address critical concerns for the Tees marine ecosystem.

• Eliminate or severely restrict overspilling during dredging operations. Trailing Suction Hopper Dredgers (TSHDs) are considered the least suitable for contaminated rivers like the Tees due to sediment dispersal and mixing. Overspilled material is more contaminated due to the concentration of hydrophobic contaminants (like PAHs and PCBs) on finer particles.
• Mandate enhanced and consistent sediment analysis and sampling. More frequent analyses for PAHs, PCBs, and Brominated Diphenyl Ethers (BDEs) are needed. Sampling must be performed before, during, and after dredging operations, with specific limits set on contamination spread. Crucially, analysis should consider the surface area of sediment particles, not just overall weight, as contaminants adsorb onto smaller particles.
• Adopt a precautionary and beneficial environmental management approach. This requires urgently exploring technologies for extracting dredged material without spillage and depositing it in lined landfill sites, rather than offshore redistribution. A full-scale Beneficial Use of Dredged Material (BUDM) Program should be commissioned, initially focusing on clean sand from outer channels for beach nourishment or construction.
• Re-evaluate the continued use of TSHDs in historically contaminated, silty upper reaches of the estuary (e.g., Billingham Reach). More precise, lower-dispersal dredging methods (e.g., environmental clamshell or auger dredgers) should be explored for targeted “hotspot” management.
• Implement an Adaptive Turbidity Monitoring Program. This necessitates real-time turbidity and Total Suspended Solids (TSS) sensors (upstream and downstream) linked to pre-agreed, tiered trigger levels (Alert, Action, Stop-Work) to allow real-time operational adjustments.
• Formally adopt an Annual Calendar of Ecological Sensitivity. This comprehensive, risk-based tool would consolidate all known ecological sensitivities into a colour-coded system to proactively schedule dredging campaigns, minimising conflicts with critical wildlife periods such as harbour seal pupping season (June-July) and peak waterbird feeding times.

• “Providential” rather than precautionary approach: The licence application assumes existing practices are acceptable due to long-term occurrence, despite significant environmental damage such as the mass crustacean die-off in 2021 and high mortality of harbour seal pups.
• Incorrect application of Marine and Coastal Access Act 2009: The application incorrectly states that PD Ports meets the exemption within Section 75 for sea disposal, as the Tees Inner disposal site (Tees Bay 'A' TY160) is not classified as “surface waters” but rather the North Sea, governed by international conventions.
• Inadequate assessment of overspilled material: The environmental impact assessment in the renewal documents fails to consider the upto 25% of dredged material that is released as overspill back into the river at dredge sites. This overspill, enriched with fine particles, carries a greater fraction of adsorbed contamination.
• Inconsistent and insufficient sediment data: The reliance on limited, inconsistent data sets with missing fundamental measurements (e.g., total organic carbon, PCBs, BDEs) makes objective comparison and understanding of the system impossible. Samples are often taken from the surface and may not be representative of the underlying dredged material. The number of samples is insufficient to comply with OSPAR guidelines given the geographical spread and volume of material.
• Elevated contamination levels: Tees sediments, particularly in overspill, show significantly elevated PAH and BDE levels compared to other ports like Southampton, indicating a persistent pollution source.
• Over-simplistic plume modelling: Current modelling is over-simplified, ignoring the significant volume and highly contaminated nature of overspilled fine particles, and the continuous, chronic pressure of maintenance dredging across fragile habitats.
• Concerning sampling recommendations: Recommendations to reduce sampling frequency based on a single “good result” are concerning, given the high variability in contamination and ongoing development activities in the Tees region.

NEMRG stresses the urgent need for a shift from a “waste disposal mindset” to one of “resource management” and genuine environmental leadership, ensuring sustainable growth for the River Tees.

MLA/2025/00263 – Tees and Hartlepool Maintenance Dredging and Disposal Licence Renewal Representation from North East Marine Research Group (NEMRG)

MLA/2025/00263 – Report of the Investigation of the Sediment Quality Data of L/2015/00427/7

Best Practices for Environmentally Responsible Maintenance Dredging in the River Tees: An Integrated Framework for TSHD Operations

2015/06/03 6 f MLP/2015/00094 has 25 samples with 25[22xPAHs] 25[8xTMs] 25[2xOTs] Phys : 2015 data set

2018/10/17 3 f MLA_2015_00088 has 10 samples with 10[22xPAHs] 10[8xTMs] 10[2xOTs] Phys : 2018 data set - Carcinus

2019/01/24M2 f MLA_2015_00088 has 10 samples with 10[22xPAHs] 10[25xPCBs] 10[8xTMs] 10[12xBDEs] 10[2xOTs] 10[8xOCs] Phys : 2019 data set - MAR00179

2019/08/14M1 f MLA_2015_00088 has 16 samples with 16[22xPAHs] 16[25xPCBs] 16[8xTMs] 16[12xBDEs] 16[2xOTs] 16[8xOCs] Phys : 2019 data set - MAR00356

2021/10/13 4 f MLA/2015/00088 has 20 samples with 20[22xPAHs] 20[25xPCBs] 20[8xTMs] 20[2xOTs] 20[8xOCs] Phys : 2021 data set - MAR01178

2023/10/19 8 f MLA/2015/00088/6 has 10 samples with 10[22xPAHs] 10[25xPCBs] 10[8xTMs] 10[12xBDEs] 10[2xOTs] 10[8xOCs] Phys : 2023 data set - MAR02085

2024/10/07 7 f MLA_2015_00088 has 8 samples with 8[22xPAHs] 2[25xPCBs] 8[8xTMs] 8[12xBDEs] 8[2xOTs] 2[8xOCs] Phys : 2024 data set - MAR02499

2024/10/28M5 f MLA_2015_00088 has 23 samples with 23[22xPAHs] 8[25xPCBs] 23[8xTMs] 23[12xBDEs] 23[2xOTs] 8[8xOCs] Phys : 2024 data set - MAR02481

2015-2024 data sets

2015 data set

2018-2019 data sets

2021 data set

2023 data set

2024 data set

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Hartlepool