From the north: cross the highway from the Hush Lake rest area, take the forest road east. Stay right at the fork(s), and follow the road south. The lake can be seen through the trees before the rec area comes up on the right.
From the south: take Hwy. 97 north from Quesnel and cross the Cottonwood River. Look for Umity Pit Road on the right before going under the train tracks. Follow the dirt road, keeping left at all major forks, until you see the lake the the trees. Continue a kilometre or two along the eastern shore until you see the rec. site on the left.
Both routes are a little bumpy, but the roads are pretty good.