The Buona Vista Battery had two Mark II 15-Inch Guns and was thought to be located within the current Police Training grounds east of the junction of Clementi Road (Then called Reformatory Road) and Ulu Pandan Road. However, we were recently contacted by the management of a neighbouring housing estate when a 2m deep sink hole opened up within their estate across the road from the Police camp.
We went to take a look and from what we can tell, it is certainly possible that this is the magazine room for one of the 15 inch guns, buried unknown for decades until recently exposed by the heavy rains when a portion of the top slab collapsed in.
The depth of the top slab (shown by the broken reinforcement bars) from ground level is 2.2m. The water level is at 3.5m below ground level. A weighted rope was lowered into the chamber which looked like it has at least one side faced with iron, and what we found was a total depth to the chamber floor at approximately 10.7m below ground level. The caretaker who discovered the sinkhole said that he initially saw a concrete floor at the bottom before it was filled by rain water, meaning the chamber was dry up until only relatively recently.
PUB had sent investigators late last year to try and go into the chamber but they gave up after they found their ladders didn't go that deep but they took photographs of inside the chamber just above the water level. We are trying to obtain those photos from PUB. Meanwhile, the sinkhole continues to widen as more soil falls through the broken slab after every rainfall. We have advised the residential management to seal the hole with timber and canvas and backfill the hole with soil to prevent more erosion.
This warrants further investigation. An RA student will be tasked to start a document search of the old archives here as well as those at the British Library to see if we can find out exactly what is located here before deciding on our next move.