What about the current health of these lakes?
We all know of Dianchi and its problems and plans. But Yangzong, for example, is treated thusly at present on Wikipedia"
"As recently as 2002, Yangzonghai had been noted for having water clean enough for drinking and swimming. But as of September 2008, it was officially considered unfit for drinking, swimming in or fishing in, when the provincial government announced high levels of arsenic in its waters. The arsenic contamination was discovered (in June 2008) when an inspection was made of enterprises operating in the Yangzonghai basin. Eight companies were found to have been engaged in illegal polluting practices. Yunnan Chengjiang Jinye Industrial and Trade Co Ltd (云南澄江锦业工贸有限公司) was named as the main polluter."
The latest info in Wikipedia about the lake is from 2008.