George Kilpatrick, pastor of St. Andrew’s Presbyterian Church in Ottawa, visited this area in 1923, and suggested this name after the daughter of a friend (11 February 1957 letter from Geographic Board of Canada, file P.1.47).

Called “Surprise Lake” by Samuel Prescott Fay [1884–1971], who was in the area in 1912 and 1914; called “Greenwater Lake” by Col. Townsend Whelen, a trophy hunter who was there in 1922.

Wrote Arthur Oliver Wheeler [1860–1945] during the Alberta-British Columbia Boundary Commission survey:

The lake is a very beautiful one, of a rich deep blue colour, some two miles in length by half a mile wide. Situated in a pocket of the surrounding heights, it is so closely encircled that it is very nearly reached before being seen. In consequence it is known locally as “Surprise” Lake. The name, Cecilia Lake, was given by Mr. Lambart and as there are a number of other Surprise Lakes, it has been adopted.

The upper valley of the lake is fairly open with scattered bodies of spruce and balsam of small size. The slopes encircling the basin of the lake are densely forested. The outlet, Cecilia Creek, flows in a broad valley showing much open meadowland along the bottom and densely forested side slopes. It has a northwesterly course of some nine miles to its junction with the Kakwa River. The 120th meridian passes within an eighth of a mile of the most northerly extremity of the lake.