Yorkshire Water has been turning the sea scarlet as it carries out tests to help understand how its sewer outfalls can affect the quality of local bathing waters.

The tests may have led some locals to think that Jaws 5 was in production, as Runswick Bay was seen to turn a lovely shade of red!

The small plumes of red water were actually environmentally friendly dye, monitored by Yorkshire Water to see how long discharges took to reach the sea and to study the effect of underwater currents and tides.

Lee Pitcher, bathing water strategy manager, said: "The dye itself is completely inert and is not harmful in any way to plants and wildlife.

"This testing is hugely beneficial as it should give us a clearer picture of how our outfalls operate and the impact they have, helping to inform our planning around future investment.

"This activity has to be undertaken during the bathing season to ensure that it takes into account weather and environmental conditions that are typical of the season to ensure that we fully understand the impact of our sewer outfalls."

The company is investing £110 million between 2010 and 2015 as part of a multi-agency project to help transform Yorkshire’s beaches into some of the best in Europe.

It’s all part of Yorkshire Water’s £3.5 billion of improvements planned for over the next five years including the provision of a more reliable supply of quality drinking water, water saving repairs cutting down on bursts and leaks, reducing the number of homes affected by flooding from sewers, cleaner rivers, and, the above mentioned cleaner beaches and seas.

So if you see the seas turn red, don’t worry, there are no sharks - you don’t need a bigger boat.

[Image: Preus museum]