U.S.-based North Korea analysis website 38 North says satellite imagery reveals significant flooding along the Kuryong River near the Yongbyon nuclear site.

The website said on Wednesday that when compared to imagery from July 22, commercial satellite images from last Thursday show a dramatic rise in the water level of the river that flows alongside the complex, the heart of North Korea's nuclear development program.

The site assessed that the flooding could be the worst in several years, adding that despite ongoing efforts to improve the river embankment against annual flooding, North Korea failed to meet the challenge of this year’s rising waters.

38 North said that the flooding may have caused damage to the complex's pumps and their power systems or clogged piping systems that draw water from the river.

It said that although Yongbyon's five-megawatt reactor appears to have been out of operation for quite some time and its Experimental Light Water Reactor has yet to come online, both would need consistent water flow to operate.