Google indexing incorrect urls

Just been looking at the stats on the sites in particular the pages that google is looking at

Clicking on any link that the stats that google is showing as visited gives a broken URL such as


But it should be


Its shortened the url but its going to (one to many /~watercoo/

This happens on ANY date that you select for googlebot.

As this is quite serious where the heck can I start to look to fix this?

update this is showing for any bot thats hit the site.