China has announced it is scrapping its decades-old one-child policy. Under the old law, couples paid a heavy fine if they had a second child. That restriction is being swept away. But the new freedom also has a cost.

Cheonggye Stream, which flows through the center of Seoul, is a popular place to relax. Its clean water is home to many birds and fish. But just 12 years ago, it was an eyesore. Its polluted, filthy water was more of a trickle than a flow. Now, 10 years after it was completed, it's an internationally recognized regeneration project.