Very few locals would know that the Prince Alfred Guard Memorial forms the certral ornamental feature of Port Elizabeth's second oldest water reservoir.
In the early 1900's it was decided to supply water to Port Elizabeth from the Bulk and Sand Rivers and the St. George's Reservoir was constructed as a part of this scheme. Excavation for the reservoir was commenced at the end of August 1906 and on 6 November 1907 the Treasurer-General, the Honourable Edgar H. Walton, turned the water into the new Service Reservoir on. The two rnillion gallon reservoir is circular, 200 feet in diameter and the depth of the water is 10 feet 6 inches.
This plague can be found at the back steps of the PAG Memorial.