Yamuna, from its origin at
Yamunotri in
Himalayas to Wazirabad barrage, travels by carrying "reasonably good quality" water. Between Wazirabad and Okhla barrage, 15 drains discharge sewage rendering the water quality after Wazirabad barrage severely polluted with
biochemical oxygen demand (BOD) values ranging from 14 to 28 mg/L and high
coliform content. Causes of pollution are municipal disposal sites, run-off from the commercial and industrial sites, soil erosion resulting from deforestation occurring to make way for agriculture along with resulting chemical wash-off from petrochemical fertilizers,
herbicides, and
pesticides. == See also ==