I remember the ones in Holland being completely automatic. If the computers determine that the seas are about to surge above a certain level they automatically close and no one can over-ride it. This is because it closes off a major sea port and the designers were concerned political & business pressures could might forced them to stay open longer than necessary (and hence, endanger the people in the port and surrounding communities).

I’m torn in agreeing with this arrangement. It’s good to know that logical decissions are being forced to be made in situations like this, but I not sure if I like the idea of total control by a machine in people’s safety.

If I remember right, people can close them anytime they want, but if they computers deem it necessary to close them, than there is really not much people can do.