Near the U.S.-Mexico border, vital signs are improving for a river that has been on life support for decades. The Colorado River is over-taxed by farms and cities in seven U.S. states and Mexico. But a historic agreement between the two countries is giving a boost to the delta ecosystem. It’s the first time water has crossed the border for a strictly environmental purpose. And it gives an element of hope to a troubled river. VOA’s Steve Baragona has the final installment of our series.