River manager says magnet fishing putting a strain on Cam Conservancy activities

The huge popularity of magnet fishing is placing a strain on the Cam Conservancy, according to the organisation’s river manager, Tom Larnach.

The popularity of magnet fishing, which involves powerful magnets trawling the river in search of valuable metals, has resulted in several incidents in which grenades and even a shell have been pulled from the river. All have required the police to attend, closing the relevant section of the river until the ordnance is safely defused.

While the Conservancy has no problem with the activity per se, there is concern about whether the navigation authority’s heavy machinery can continue to be safely used on the river.

“I’ve been at the Conservancy for three years,” Tom told the Cambridge Independent, “and the first year no one had heard of magnet fishing. But since then it’s become very popular, not just along the Cam but in the UK generally.

“The problem is that metal detritus is being left along the side of the river bank, which makes it look pretty awful. We ask magnet fishers to take everything they get out of the river home with them.”

When the first grenade was retrieved from the water last summer, it seemed like a one-off.

“At first it was one or two, but now we’ve sat up and asked about our own safety, and we’re now in contact with the Cambridgeshire constabulary. We plan to see if there’s anything we should do in mitigation – anything we ought to be doing.

“We’re not immediately planning to do any more trawling – collecting stuff from the river – because that’s done mostly in the winter, with some reactive responses during the rest of the year, such as when a supermarket trolley is found in the river.”

So what is magnet fishing all about?

“Mainly they’re fishing for stuff, it’s actually fairly cool, they want anything with iron in it, which sticks to a magnet, so it could be swords, grenades, bullets… They’re looking for historical artefacts, and maybe precious metals.”

Tom doesn’t believe the activity should be regulated.

“Personally, as long as they take what they find away with them, then it’s not doing any harm and in fact is helping us to get all the rubbish out of the river.”

So is it worth the risk?

“My question is ‘can you reassure me the river is safe to operate heavy machinery on?’. Because I need to operate heavy machinery on the river. But beyond that, there does seem to be a large volume of finds, so is the frequency of the ordnance being found above and beyond other cities in the UK? Could it be that there was some sort of munitions barge that had an accident on the river, during the war perhaps?”

Local historian Mike Petty told the Cambridge Independent there is “no evidence of ammunition movement along the river”.

A Cambridgeshire police spokesperson said: “There are all sorts of things that can be pulled from waterways when magnet fishing, including dangerous objects or items which may have been used in crime.

“Rather than risk anyone’s safety, or potentially contaminating evidence, if you find a weapon of any sort, or something which may be a form of explosive device, please leave it where you found it and call us so it can be safely and properly recovered.

“Additionally, magnet fishers are advised to seek permission from the waterways owners/controllers and agree what to do with anything else retrieved from the bottom. We would always advise avoiding littering by leaving items on the side of the water.

“Magnet fishing is becoming more and more popular and we want to highlight this advice so people can enjoy their hobby safely.”

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