No doubts have been cast on the quality of engineering in the project, but concern has been raised over possible long term harm to the marine ecology caused by heavy metals such as cadmium, lead, arsenic and zinc that are released from furnace slag and fly ash dissolved in water.
工程品質雖未受到質疑，然而，用來築堤的爐石、飛灰溶解在水中釋出的重金屬，如鎘、鉛、砷、鋅等，長此以往是否會影響海洋生態，卻引起有心人士的關切。