Local History

There are actually two of these curious structures but why were they built? The answer it seems lies in scientific experiment - they were both built in the 1970s as a feasibility study into water storage.

Looking out to the island

The plan was to see whether large parts of the Wash could be converted into a freshwater reservoir.  But building these test lakes on a tidal estuary - soon meant their fresh water was becoming salty. It also cost a large amount of money -three million pounds for the trial alone.

The plans were soon shelved, and the trial banks were abandoned. But they've now gained a new importance as a breeding bird colony, around three thousand pairs of sea birds now nest on the outer bank.

Tammy Smalley - Wash Estuary Project

Tammy Smalley, Wash Estuary Project Officer says "Some of the materials they used to build the banks were dredged from the wash so were saline in nature anyway. So you're not going to get fresh water in a salty environment - and that was the reason it was abandoned. But how many estuaries can you go to in the UK and see a 1970s experiment still there in the landscape, that has become important for wildlife in its own right?"

So now there's a whole new use for this thirty year old experiment. These are two unique islands left behind by science - which have now been taken over by Nature.

It seems many people are curious to what these structures are, according to Simon Cooter from Natural England. "I get regular emails and phone calls asking what this strange structure is out in the Wash - whether a meteor's landed in the Wash or aliens have landed or something! They're very significant as they're major landforms in the area. They're the only hills in the Wash. The outer trial bank is a breeding sea colony for sea birds. They're declining in a lot of their breeding habitats but here they're doing very well."