In 1909 the company was acquired by the Prestatyn UDC (Act 1909). In 1910, total consumption 6,771,400 cu.ft.. Two new luteless purifiers built, 12'x12'x5' deep. The Prestatyn UDC awarded a contract to Mr W.D. Prescott for £245 for extension to the gasworks. In 1922 "The Prestatyn Urban District Council have decided to obtain a loan for the construction of a new gasholder, a retort house, and a railway siding into the works. Two more purifier boxes, matching the 1910 pair built in 1923. A third gasholder (later known as No.2) was built; 154,000 cu.ft. two-lift spiral in a steel tank. The original holder became a tar and liquor tank. The second holder of 36,000 cu.ft. (two-lift, frame guided) was still in use in 1936. In 1926 a New 250,000 cu.ft./day water-cooled vertical tube condenser installed. Also, a new Livesey Washer, 500,000 cu.ft./day capacity. In 1930 the town received an electric supply received; a substation was built on the gas works. Gas sales declined in 1930, 1931 and 1932, but resumed their growth in 1933 and by 1935 exceeded the earlier maximum. In 1936 Total sales 46,245,700 cu.ft.. 1.5 miles of mains. C.V. 500 B.Th.U.s. Construction of new plant began 17/8/1936; it was commissioned on 14/5/1937. Other new plant approved in the same scheme was a Weck centre valve for the purifiers (£600 from Robert Dempster), one new exhauster set, 25,000 cu.ft./hr (£255 from Waller) and a Connersville type station meter, 25,000 cu.ft./hr (£345 from W.C. Holmes). Total cost £12,012. In 1937 Vertical W-D retort house inaugurated on 25th May S. Edwards, Gas Engineer: Col. W. M. Carr, Consulting Engineer. Capacity of new retort house 242,000 cu.ft./day. Cost £10,812, complete with steam lift, waste heat boiler and water softening plant. Four upwardly heated retorts, capable of carbonising 4.2 tons of coal/day each, 21 feet high and 44"x10" at the top. Railed skips for coaling and coke to producers, and for taking coke into the yard. No coke plants. The annual report in 1949 gave a make of 97m cu.ft.. The Prestatyn gasworks closed in November 1955 following a supply of gas from the North Wales Gas Grid. The gasworks were visible on the 1898 to 1994 OS maps.