At Siuslaw bridge in Mapleton, leave Highway 126 and go south on Sweet Creek Road. A beautiful 11 mile (18 km) drive will take you to the first trailhead. Parking lots are available at each trailhead. Eleven waterfalls in all.
Sweet Creek Falls is 13 miles south of Mapleton on Lane County and Siuslaw National Forest roads. A good way to visit it is to drive through the Coast Range, between Florence and Reedsport, combining it with a stop at the North Fork Smith River Trail.
The falls is on Sweet Creek Road, which turns to Forest Road 48, south of Mapleton. The road is paved in this direction to the trailhead, though it switches to gravel from there if you keep going south to cross the Siuslaw/Smith River divide.
A 2.5-mile trail follows Sweet Creek, with trailheads at Homestead, Sweet Creek, Wagon Road and Beaver Creek Falls (north to south). I opted for the 0.4-mile trail from the Sweet Creek trailhead to see the Sweet Creek Falls, which is in a shady site (welcome on a hot day) with a nice pool at the bottom. The low flow of summer must have cut down its awe factor, but I bet the rainy season is a great time to see it at its best.
Nevertheless, the trail is in a scenic section of the national forest and worth the slight diversion while driving between Eugene and Florence. Since I had to get home, I couldn't spend too much time.
Keywords: Free, Just you alone / As a single, Scenic location, Remote, Local, Summer (June - August), With kids, As a couple, Fall (September - November), Spring (March - May)