Technical regulations and administrative standars pose an increasing influence on society, where science and technical advance covers every field of activity. Public Administrations play an important role on public technical permits, along with private standards. In relation to water works, dams have to cope with potentially severe risks on lives, property and the environment. When the public fostering of these water works is already over, a special focus on security of hundreds of dams is needed, as well as its influence upon the water permits legal regime.