Prohibited by Building Code
The National Electric Code (NEC) is the building code for the entire United States.
The (2011) NEC 411.4(B) prohibits the installation of low voltage systems within 10 feet of any pool, spa or hot tub, unless specifically permitted by NEC Section 680.
So what IS "permitted" ?
NEC 680.22(C) defines the requirements for low voltage lighting, at any operating voltage, around indoor or outdoor swimming pools.
The only discussion about low voltage lighting around swimming pools is addressed in NEC 680.23(A)(2). It only discusses the underwater light fixtures.
Because these section do not specifically permit the installation of low voltage lighting fixtures adjacent to a swimming pool (as required by NEC 411), it is still prohibited.
Until the NEC is updated or changed, low voltage lighting fixtures are prohibited from being installed within 10 feet horizontally and 12 feet vertically from the water.