The quality of seawater along China\'s coasts degraded in 2012. That is according to the report released on Wednesday by China’s State Oceanic Administration.Around 68,000 square kilometres of nearshore waters were degraded to the worst quality levels. It was a 24,000 square kilometre increase compared with 2011.The State Oceanic Administration monitored 8,400 stations across the country.The report also said that a total of 170,000 square kilometres of nearshore waters have not reached the first grade of seawater quality, which is suitable for hosting marine life and natural reserves.In 2012, about 19,000 square km of neashore waters were affected by eutrophication, a process in which water bodies receive excess nutrients that stimulate the excessive growth of algae and weeds.