Algal contribution to dissolved oxygen in small hilly streams-A case study

Hathli is sub-tributary of river Beas in outer Himalayas. It is getting polluted due to wastewater of Hamirpur town in Himachal Pradesh, India. The pollution impact is severest in the low flow months. Steep slopes, pools, riffles and small waterfalls thus characterize the stream. the streambed consists of stones and cobbles. All the stones in the streambed are heavily coated with a greenish layer of algae. The paper describes the quantification of oxygen production due to the presence of attached algae in the stream and need to modify the existing models to predict the water quality of hilly streams.