The Chongquing section of the Yangtze river in China has turned red. We were first alerted to this by Bill Bishop.

Authorities are investigating the strange occurrence — some are speculating that it's just red silt. Bacteria called Chromatiaceae that thrive in low-oxygen environments are also known to turn massive water bodies red.

新华网很淡定

重庆长江水变红疑受污染 环保部门称未监测出有毒物质

9月7日，重庆朝天门两江（嘉陵江、长江）交汇处，偏红的长江水与嘉陵江水泾渭分明。当日上午，一组重庆朝天门长江段江水呈现赤红色的照片引发网络热议，6日晚重庆南岸区等地出现大范围停水，部分网友和重庆市民怀疑江水受到污染。重庆市环保局表示，尚未发现违规排污行为，江水中未监测出有毒物质。在这组照片中，重庆朝天门港口长江段江水呈现赤红色，与两岸的高楼、绿化地带形成鲜明对比，让人感觉江水水质出现明显异常。重庆市渝中区环保局和巴南区环保局工作人员在接受媒体采访时表示，初步推测江水变红是长江上游汛期导致泥沙量较大所致。　　新华社记者刘潺摄