I'm disappointed with this story. The urban legend was that they'd laid some tiles in the bottom of the pool that changed colour when the water was heated, so that when they showed the finished job off to him (heated, so he could dive in) the whole of the bottom of the pool was a uniform sea green aquamarine, or whatever, but in the morning, when he came down, and the water had cooled before he turned on the heating unit, the change colour tiles spelt a huge red "LFC" right across the middle.
It does rather pale in comparison with that similar even in the US where some new yorkers buried some jersey under a pitching mound in boston or vice versa.
And didn't Newcastle-supporting builders put Newcastle shirts in the foundations of the Stadium of Light?
And didn't the Burnden Park tea lady put a gypsy curse on Bolton's next 'big signing' after they moved to the Reebok? Which turned out to be Dean Holdsworth, who then missed that sitter in the FA Cup semi-final against Aston Villa? Or something?
Oh, the Yankees story was hilarious, but not as hilarious as the fact that the club tore up the building and showed off they had unearthed it before it became a curse.
I am not sure if they are all urban myths but there was a story about there being Argentinia and Poland shirts secreted inside the arch at Wembley by builders.
Was there really a train under the pitch at old Wembley and , if so, what happened when the new one was rebuilt?
On the subject of Argentinia, which apparently new nation Harry has just mentioned...
In the late '70s (I think) Independiente fans were said to have buried seven dead cats in the moat around the pitch at Racing's stadium, an enormous concrete bowl built during the 1950s which carries the endearing name 'Estadio Presidente Juan Domingo Perón'. At the time, the moat was filled in with concrete.
Racing went decades without a championship. And then in 2000, Reinaldo 'Mostaza' Merlo took charge, and had the moat excavated. The cats were found, and presumably given proper burials. In 2001, Merlo managed Racing to the Primera A Apertura title.
There are similar stories across South America I imagine - there are certainly a few involving the Maracana and other Brazilian grounds, as anyone who'd read 'Futebol' by Alex Bellos will know.