It is illegal to let your dog swim in the reservoirs, but how about if it ran in without your wilful wanting it to. Have you committed an offence?
the waterworks ordinance (cap 102) says it is prohibited if one “washes or causes or permits any animal to enter [reservoir, or waterway leading to reservoir]”.
If you didn’t wash the dog, didn’t push or bring the dog to the water and didn’t stand idly by, would it be an offence?
My dog sometimes runs down from the trail and takes a quick dip in the water to cool down. I won’t notice it until it’s too late, and if I’m up ahead I won’t notice it until my dog comes back to me. The dog is well trained to leave other people alone and come to me, but when it is hot it is hot and it sneaks into water when it thinks it can get away with it.