I wouldn't call the Hudson River's water 'blue'.

It's more like a murky brown-green to me.

'In the previous attempt, thick mud had proved too strong for six "tractor tugs" exerting some 30,000 horsepower.

A battle occured this time, too -- the blue water was churned dark brown as tugboats strained to inch the giant vessel away from its longtime home.'

USS Intrepid freed from mud