A tangled, congealed mound of flushed wet wipes and sediment that has lain on the foreshore of the River Thames near Hammersmith Bridge is finally set to be excavated. The Port of London Authority (PLA) and Thames Water are co‑ordinating an operation to remove what their surveys show is roughly 180 tonnes of material — described by officials as the size of two tennis courts and up to a metre high in places — in a clearance expected to take up to a month when tides and access allow. St Paul’s School, Barnes, has agreed to provide site access so an eight‑tonne excavator can work from the foreshore and the waste will be taken away for responsible disposal. (This account is based on official statements from the Port of London Authority and reporting of the planned work.)

High‑resolution sonar and laser surveys published by the PLA underpin the decision to tackle the mound mechanically for the first time. The bathymetric analysis shows how years of flushed wet wipes have bonded with sediments to form a distinct mound that alters riverbed form and local flow patterns, and which PLA data suggest is damaging habitats. Volunteer monitoring by Thames21 — which has run repeated “Big Wet Wipe Counts” at Hammersmith since 2017 — has provided corroborating, on‑the‑ground evidence: tens of thousands of wipes recorded and hundreds of thousands of items collected during citizen science events. Together, these datasets have been used to plan the removal and to argue for wider preventive measures.

Until now the clean‑ups have largely been manual: volunteers wading and hand‑collecting material at low tide. The coming operation marks a step change in scale, with mechanical excavation from the foreshore and removal in skips. Organisers say the work will be scheduled around tidal windows and undertaken carefully to limit disturbance, with the removed material disposed of through appropriate waste channels. Thames21 volunteers, who have persistently campaigned for action, will continue to monitor the site afterwards.

The Port of London Authority’s director of sustainability, Grace Rawnsley, said in a PLA statement that the mound has been “a source of environmental harm and an embarrassment to the capital,” and described the project as the first attempt to execute a mass mechanical removal of wet wipes on the tidal Thames. The PLA has framed the clearance as part of a broader push to bring “innovation and investment” to protect the river and its wildlife.

Thames Water has emphasised the operational and environmental drivers behind the removal. In a company statement its Tideway integration lead noted the clearance is a visible reminder that flushing non‑biodegradable items does not make them disappear, and highlighted the scale of the broader problem: Thames Water estimates it removes some 3.8 billion wipes from its network each year. The company has also announced a new £1.8 billion investment package for 2025–2030 to improve river health across London — funding it says will go towards reducing discharges from sewer overflows, upgrading treatment works and increasing maintenance and screening.

For campaigners the clearance is vindication of long‑running efforts. Chris Coode, chief executive of Thames21, said the organisation’s volunteers have spent years building the evidence base and urged stronger upstream action: “Plastic wet wipes have no place in our rivers or natural environment,” he told reporters, and called for bans on plastic‑containing wipes, clearer labelling, more sewer screening and faster upgrades to sewage infrastructure. Thames21’s briefings also stress the role of wipes as an emerging source of microplastics and outline how mounds of sanitary waste can change foreshore morphology and harm intertidal wildlife.

The mechanical removal comes against a backdrop of larger infrastructure changes intended to reduce sewage discharges into the Thames. Tideway, the 25 km “super‑sewer” project, announced final connections in February 2025 and says the tunnel has already prevented millions of cubic metres of sewage entering the river and should cut spill volumes substantially once fully operational. The PLA’s recent “Clean Thames Manifesto” and reporting by other outlets have pushed for collaborative targets and earlier reductions in sewage spills, emphasising that water companies, regulators, charities and river users must act in concert.

Environmental and operational experts warn that the Hammersmith mound is symptomatic of a wider problem. PLA and Thames21 material shows how accumulated wipes can trap sediment, change local hydraulics and smother habitat, while utilities point to the cost and public‑health implications of blockages in the sewer system — Thames Water’s operational accounts of large fatberg clearances illustrate the complex, labour‑intensive nature of such work. Removal at Hammersmith is therefore being presented both as remedial action and as a focal point for advocacy on behaviour change and regulation.

The clearance will be closely watched as a test of whether mechanical removal, combined with upstream investment and tighter regulation, can reduce visible pollution in the tidal Thames. Local politicians and campaigners have welcomed the move: Fleur Anderson, MP for Putney and neighbouring areas, called the operation “a huge moment” after years of campaigning, and urged that the outcome inform national measures on wipes and sewer management. All parties involved say they want the work to be the start of a coordinated effort to stop more material accumulating, not merely a one‑off tidy‑up.

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Source: Noah Wire Services