Urbanisation, influx of pilgrims, fertilizer-intensive farming, and indiscriminate sand-mining have impacted on the water quality of Manimala river, a major source of drinking water in Kottayam and Pathanamthitta districts.

A report published in Environmental Monitoring and Assessment, an international journal devoted to progress in the use of monitoring data in assessing environmental risks to man and environment, highlights the deterioration in water quality caused by human intervention, especially in the upper reaches of the Manimala river.