The Central Pollution Control Board, CPCB, has identified 150 polluted stretches of rivers across the country. Giving this information in a written reply in the Lok Sabha on Wednesday, Environment and Forests Minster Jairam Ramesh said the pollution load on rivers has increased over the years due to rapid urbanisation and industrialization. He said that domestic sewage is the major source of pollution of rivers besides industrial and other non-point sources of pollution. Mr. Ramesh said Centre and State governments are making collective efforts for conservation of rivers through National River Conservation Plan.