<p>A layer of thick foam flowed down the Yamuna river, next to New Delhi, after rainfall on July 2, prompting comments about ongoing pollution concerns.</p><p>The Yamuna River, considered sacred to some, has been at the center of a number of environmental controversies</a>.</p><p>Toxic foam has been spotted on the river a number</a> of times</a>. Credit: Twitter/@salman16092013 via Storyful</p><br />
