An article, The new 'Bowen Park', on page 2 of The China Mail, 1885-02-27, described Governor Bowen's visit to the racecourse to "turn the first sod", and start the project to drain and re-develop the land. Bowen said the project would "convert this marshy and malarious swamp on which we are now standing into a place of public resort." Based on this I've guessed 1885 as the date the pond was dug, but corrections welcome!
We've got a better idea of when it was filled in again.
After the Hong Kong Golf Club was founded in 1889, their first golf course was laid out here, on the flat land inside the racecourse. However, that large pond caused problems for the golfers: "One hole, the 8th, became known as 'Old Misery' on account of the pond which swallowed up balls, scarce at the time." See page 181 of The Encyclopedia of golf
I'm guessing the golfers included a few members of government, as they soon had the pond filled in: "Prior to 1890 there was a large round pond, at the northern end of the land inclosed [sic.] by the race-course track, which was filled up in that year for the convenience of golfers, who started the first Hongkong Golf Club there in 1889 (now known as the Royal Hong Kong Golf Club)." See page 355 of Old Hongkong by Colonial
The pond in the newspapers
Thanks to Moddsey for pointing me to these articles in the newspapers with more about the pond.
THE EXTENTION OF THE RECREATION GROUND AT HAPPY VALLEY on p.2 of Hong Kong Daily Press, 1890-02-13:
Then on p.2 of Hong Kong Daily Press, 1890-09-01, a short article records a drowning in the pond, and also that the pond was in the process of being filled in:
1929 Comment on the Happy Valley 'Lake'
From an old timer who had been in Hong Kong for 45 years back in 1929.
" I remember when the racecourse in Happy Valley was a lake. It was filled-in because so many people committed suicide in it." Page 5 of the HK Daily Press dated 6 February 1929 refers.
Legislative Council voted to fill pond on 9th June 1890
"RECREATION GROUND, HAPPY VALLEY.
17. - The improvements estimated to cost $16,000 for which the sum of $8,000 to be expended this year as voted by the Legislative Council on 9th ultimo consist in filling in the round pond and improving the surface. The work has been commenced. It is in my opinion very desirable that the drainage of this Valley, for which much has already been done, should be completed by improving the watercourse on the west side of the Race Course, diverting it to the westward from the near, the Grand Stand to a point near the Bowrington Sugar Refinary, removing the weir oppoiste the refinery, and contracting the width of the canal from the refinery to the Harbour. I hope shortly, in consultation with Mr. Chardwick (in so far as the question of main drainage is concerned) to be able to submit plans embodying these proposals, which must tend to improve the sanitary condition of the locality."
Source: Hong Kong Daily Press, page 3, 22nd July 1890
Source: The China Mail, page 4, 22nd July 1890
Source: The Hong Kong Telegraph, page 3, 22nd July 1890