Dog Lake is a lake in northwestern Ontario, Canada which drains south through the Kaministiquia River to Thunder Bay on Lake Superior. It was on the voyageur route to western Canada. Its name comes from a large aboriginal effigy of a dog on a nearby hill. The lake is primarily fed by Dog River and seasonal melting of the snow. It includes Silver Falls Proviā¦Dog Lake is a lake in northwestern Ontario, Canada which drains south through the Kaministiquia River to Thunder Bay on Lake Superior. It was on the voyageur route to western Canada. Its name comes from a large aboriginal effigy of a dog on a nearby hill. The lake is primarily fed by Dog River and seasonal melting of the snow. It includes Silver Falls Provincial Park and it is a back-up drinking water supply for the City of Thunder Bay. Development of new summer homes is not permitted. As such, properties on Dog Lake are in high demand when available and the body of water has little boat traffic unlike lakes in Southern Ontario.