Port of London Authority staff perform a wide range of duties that facilitate the safe navigation of the tidal Thames for all users.
Whether it’s monitoring river traffic, patrolling the Thames or just clearing the port of driftwood – these responsibilities are as numerous as they are key to the smooth running of the port.
A perfect example is the shotblasting bay at the PLA’s Denton base. There, workers don heavy-duty protective clothing to clean and strip rusted and/or damaged river ‘furniture’ by firing a high-speed stream of steel particles at it. It means rusted navigational buoys that have seen better days get a new lease of life as sea creatures and iron oxide are blasted off. Then, a few coats of paint are added and the buoy is carefully placed back in the Thames, ready to guide ships

entering or leaving the port.
Tony Marsh has worked for the authority for 15 years and is one the main shotblasters doing a vital job.
He said: “The nav buoys can get quite rusted, their paintwork can get bleached by the sun, or they may get bumped into occasionally by ships.”
PLA staff will carefully remove a tarnished nav buoy using a quay crane or salvage vessel, only to find the lower half of the buoy is covered in sea life; barnacles, shells and all sorts of maritime mess that it picked up while partly submerged in the Thames.
That layer of gunk must be jet washed, and later any corroded metal must be removed by shotblasting, before the five-tonne buoy can be repainted and put back into use.

Inside the sealed blast bay, Tony goes to work on the river-worn furniture. The shot and debris falling off the buoy is collected by a drain on the floor. A mechanism connected to the drain shifts used shot back into the compressor, so that it can be used over and over again.

“After the shotblasting is done we spray the buoy with Intershield, aluminium paint, and later coat it in dark grey Interguard paint”, Tony said. “The process binds the paint with the metal but the two coats must be applied within 48 hours of each other so that the bonding happens properly.”

Multipurpose deckhand Tony says getting one nav buoy as good as new can take around a week, but the length of time varies according to the buoy’s size and state.

“I really enjoy shotblasting, cleaning up and spraying buoys or whatever else, just seeing a job through. Completing the job is very satisfying because you can see the buoy is in a better state than it was before. It’s an important job because it helps keep the river safe.”

Find out more about the PLA’s work on 95 miles of the River Thames: