[CaptainNH]

I think you've done a reasonable job given that you were starting with 10 identical over-exposed shots.

I know the spot well and it can be a nightmare to get properly exposed shots - bracketing was a fine idea.

As a result of your original shots being over-exposed, the water has remained blown out through the HDR process.

I'm not sure what process you went through to get this HDR, however, you ought to be able to adjust the exposures of the original shots before going HDR.

And don't worry, you're not the only one to have forgotten to press "set" when setting up the bracketing.