It’s only about 30 km from Winfield near Kelowna but it takes about an hour to drive to Doreen Lake. The Forest Service Recreation Site is a fantastic site with aobut 10 known campsites and with a couple of outhouses. (the one I used on July 23 2011 wasn’t too clean though)
The campground is user maintained and the competition for the campsites is quite heavy! There is usually one available on non-long weekends though. The lake is beautiful and the campground is perched on a nice rise above the lake. There are many recreation sites near by if you do not find a space here. The Aberdeen Plateau, upon which Doreen Lake is located, has dozens of lakes and campsites to choose from! Just go.
Here is Trails BC description:
Site Description:Recreation site with cartop boat launch on Doreen Lake – a small remote flay fishing only lake, canoeing and boating located in the back country wilderness forests behind the small community of Winfield, BC in Lake Country. It has an abundance of rainbow trout.
To drive in almost any two wheel drive to Doreen Lake, take Beaver Lake Road from Winfield and you will see Doreen Lake on the left well after Beaver Lake.