Adopted in the 10th Report of the Geographic Board of Canada, 30 June 1911.

Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office

After Lieutenant Peter John Leech, lieutenant and astronomer of the Vancouver Island Exploring Expedition, 1864. Gold was discovered in Leech river by the expedition, and during the latter part of 1864 and in 1865, it is said upwards of $100,000 worth of gold was taken out of the stream..... Mr. Leech, a native of Dublin, came to this coast with the Royal Engineers, under Col Moody, in 1858, and remained with the command at New Westminster until it was disbanded in 1862. He then engaged in civil engineering and after the exploring expedition was one of the party who surveyed the route for the overland telegraph line which was to have extended across British Columbia, Alaska, Siberia and Russia to the European capitals. This work was abandoned on the successful completion of the second Atlantic cable. Leech was later city engineer of Victoria... Died 6 June 1899.

Source: Walbran, John T; British Columbia Coast Names, 1592-1906: their origin and history; Ottawa, 1909 (republished for the Vancouver Public Library by J.J. Douglas Ltd, Vancouver, 1971)