Hugh Allen Off-Leash Dog Park is an unfenced grassy area off Pacific Avenue, just west of the intersection at Howe Road. Parking is available on Howe Road.
Unfortunately we missed the entrance to this park because the internet misled us, and maybe our morning coffee hadn't kicked in yet. Upon further review, and with the help of Google Maps, we found the park entrance just up the hill from where we were looking. Google Street View has a good picture from the street if you want to go check it out.
Having said that, there is a large fenced dog park 200 meters up the hill at Aberdeen Hills Off-Leash Dog Park. It may be a more appropriate place to play off-leash and has spectacular views of the valley and South Thompson River.