A son of James Loch (his brother was Lord Henry Loch, and his uncle was Admiral Francis Erskine Loch), Granville Gower Loch entered the navy in 1826 and had risen to the rank of commander by 1837. He attained post rank and went on the Obina campaign as a volunteer in 1841. He published an account of the campaign "The Closing Events of the Campaign in China" (1843). He was employed in Nicaragua in 1848, in the same year he was awarded the C.B.. He took prominent part in the Second Burmese War, 1852–53. He was shot and killed while attacking Donabew and was buried in Rangoon.