Creating barriers

Many large cities have a problem with men urinating in public areas, particularly in areas with bars or homeless people. San Francisco thinks it has found a solution, one used with success in Germany. Walls are painted with a urine-repellent paint called Ultra-Ever Dry. The paint creates a barrier of air in front of the surface that will "completely repel almost any liquid," according to its maker. 

Those with a need to urinate on a wall are warned by signs written in English, Chinese and Spanish, that say: "Hold it! ... seek relief in an appropriate place".