Methane emissions from reservoirs behind Dams

http://environmentalresearchweb.org/cws/article/news/48649

“No time to waste” on transition to green energy

Meanwhile, hydropower would produce such large emissions that it could add to global warming more than coal power alone for a good 60 years or so. “Hydropower is often associated with high methane emissions [due to] the decay of organic matter in the flooded land surface,” explained Caldeira. "There may be some niche locations where additional hydropower could be environmentally desirable, but more often environmental considerations weigh in favour of removing dams, not building them."