Troubled water -

Pangani River, also called Ruvu River, is the biggest river in northeastern Tanzania. 
The Pangani rises on Kilimanjaro mountain and flows southeast for some 400 km to enter the Pemba Channel of the Indian Ocean, southeast of the Kenyan border. The river falls, just west of the small town of Pangani.

According to a 2011 study titled “Economics of climate change in Tanzania”, published by the Tanzania government in collaboration with the United Kingdom’s Department for International Development, changing weather patterns in this East African nation will make its coastal communities more vulnerable to rising sea levels.
The freshwater drinking supply of the coastal town of Pangani and the near villages is becoming increasingly contaminated as salt water steadily seeps in from the Indian Ocean. 

This is the story about the last part of the river before it ends in the Indian Ocean.