So I suppose we should be complaining to the council that they won't allow us to use that perfectly adequate camping ground. (Within a couple of hundred yards of a perfectly good railway station, and several car parks.) But council's don't own fields on their own behalf - they own them as agents of the residents.

If I was a resident I'd be complaining to them - and I'd be complaining about that handy little toilet/washroom being neglected and not kept in decent prder. How do the people with boats moored down there feel about that?

It sounds as if the people of Leigh on Sea are being let down by their council.

Looking at the google map of Leigh-on-Sea at high magnification and "satellite" - it really doesn't look as if there is any shortage of ample suitable places to pitch a few tents within easy walking distance of the Leigh Old Town. And adequate car parks as well.