Goosefoot Orache type plant?

[awarner]

Found this today in a reed bed by the Hamble so brackish tidal water quite low growing, no more than 30cm with a white four petal flower.
The leaf is like a succulent and quite fleshy in appearance. I do get common orache but these leaves are smoother as well as smaller.

 

[Muddypaws]

With distinctive white petalled flowers it is unlikely to be a member of the goosefoot family.
My first thought was a Scurvygrass, possibly English Scurvygrass (cochlearia anglica) , it is coastal, with fleshy leaves, the upper leaves clasping the stem like you show in the photo.

 

[awarner]

Thanks for that, certainly looks like English Scurvygrass, it was the leaf structure that sent me down the wrong path.
Just when I though I caught all the plants last year more new ones appear.