The combined effect of heavy rainfall, snowmelt and breaching of the Chaurabari lake could have resulted in an water outflow with large amount of debris which devastated the Kedarnath valley, the Lok Sabha was told today. Minister of State for Environment Mahesh Sharma, in a his reply to a question, said the devastation in the Kedarnath area is not mainly due to the glacier melt. "The devastation in the Kedarnath area is not mainly due to the glacier melt. The combined effect of very heavy rainfall, heavy snowmelt and breaching of the Chaurabari lake in the upstream could have resulted in a gushing outflow with large amounts of debris which devastated the entire valley," he said. Sharma pointed out that very heavy rainfall in the entire catchment area further increased the magnitude of floods. Uttarakhand had witnessed massive devastation in the June 2013 flash floods. To a question whether natural sources of water, such as lakes, waterfalls and glaciers are shrinking fast in various cities, including the Himalayan region, due to climate change and global warming, he said according to studies conducted by the Geological Survey of India, the glaciers in Himalayan region are receding at varying rates in different areas. "As per these findings, recession of glaciers could result from natural cyclic processes and other factors including, inter alia, global warming," the minister said. For conservation and management of identified wetlands and lakes in the country, the ministry is implementing the National Plan for Conservation of Aquatic Eco-systems (NPCA) on cost-sharing basis between central government and the respective state governments, he said.