In a laboratory 10 miles east of downtown Los Angeles, a mechanical penis sputters to life. A technician starts a timer as a stream of water erupts from the apparatus's brass tip, arcing into a urinal ...

We take it for granted that urinals flush. With each pull of the lever, gallons of clean water come to whisk away a few ounces of pee. If you think about it, it’s actually pretty wasteful, and the ...