Sparth Reservoir is one of the most picturesque spots in the Colne Valley area.

But its idyllic nature can be deceptive as one family found out on Sunday afternoon when two girls almost drowned after getting into difficulties at the open water swimming venue.

Fortunately there were plenty of strong swimmers around who ensured the day did not end in tragedy.

But there have been attempts to stop all swimming at the venue in a long-rumbling row that has been going on for at least five years.

In October 2011 dozens of people defied British Waterways, now the Canal and River Trust, the custodian of the nation’s waterways, to take a dip in the reservoir during the warm weather.

More than 100 protesters swam in the reservoir which is situated between Marsden and Slaithwaite after it installed a new ‘no swimming’ signs at the site.

Sparth Reservoir in Marsden.

The organisation said a by-law banned people from going into the reservoir but campaigners claimed swimmers have used Sparth Reservoir for decades.

Delving back into the Examiner archives they found 12 articles which referred to people swimming in the reservoir with the earliest story dating from 1950.

A report from June 28, 1971 reads: “Only 102 swimmers turned out for the Huddersfield and District ASA open water test at Sparth Reservoir near Marsden yesterday.”

Sparth Reservoir at Marsden

Fiona Weir who has swum in the reservoir for 25 years and is a leading member of Friends of Sparth Reservoir, said: “For five years we have been talking to the Canal and River Trust, the successor body to British Waterways.

“It’s been a great bit of work. About a month ago new signs went up giving safety advice and the No Swimming ones went down.

“Sparth is such a special swimming spot, with a long and unique history.”

But she stressed that the reservoir was not designed to be used by inexperienced or nervous swimmers or children.

David Baldacchino, waterway manager for Canal and River Trust for the Manchester, Pennine and Potteries area said: “We were very concerned to hear about the incident at the weekend and relieved because it could have been much more serious.

Sparth Reservoir in Marsden.

“At Sparth Reservoir, because of the history of people swimming here, we have put special signs up that highlight the risks.

“We would urge everyone to follow our advice and find other ways to cool down”.

The Trust said that of the 400 people who drown in the UK every year, more than half the fatalities happen at inland waters such as canals, rivers, lakes, quarries and reservoirs.