Children are putting themselves at risk on a reservoir building site.

That’s the fear of Yorkshire Water who admit they are “very concerned” about the safety of children seen entering their construction site at Butterley reservoir in Marsden.

The company is urging children to keep out and keep safe.

Yorkshire Water’s contractors, Mott MacDonald Bentley (MMB), have just started work on the £5m project to replace the spillway at Butterley reservoir. The scheme is to make major changes to the historic spillway at the reservoir.

Ryburn Reservoir overflowing during the floods

Video thumbnail, Ryburn Reservoir overflowing during the floods
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But workers have already seen children gaining unauthorised access to their site. On two occasions boys have been seen jumping over the wall on the access road, which is currently closed to the public, and entering the site.

A group of children were caught sledging down the reservoir embankment and one of the group came into the working area and climbed onto a 13 tonne excavating machine.

Lee Laherty, Yorkshire Water Project Manager said, “Our sites and the large machinery might seem exciting but they are very dangerous.“

Yorkshire Water's Holme Valley reservoirs, Digley Reservoir spillway.

Children must keep out of the site and away from danger.

“A colleague visited Marsden Junior School last Thursday to talk to the students about the water cycle, how we treat waste water as well as our project at Butterley reservoir, and the safety message was reinforced with the students then.

Video thumbnail, Butterley reservoir
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“Additional safety signs, targeted at children, have also been put up around the site perimeter. We’d be very grateful to local parents if they can explain to their children why they should not enter our construction site.”

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The company has also reinforced the dangers of swimming in reservoirs in readiness for warmer weather and school holidays.

A spokesman said: “Reservoirs may seem like a good place to take a swim or cool down but this couldn’t be further from the truth.

“When fatalities occur - and they do across the UK each year - it’s often the temperature which is the most significant factor. Reservoirs are deep and the water doesn’t flow like in rivers or the sea so the temperature rarely rises much above 12C. It really doesn’t matter how well a person can swim as it’s the cold which paralyses muscles, meaning the victim is unable to stay afloat and if help doesn’t arrive within seconds, they will drown.”