Lake Mills was a more popular and better recreational venue than the more readily-accessible lower reservoir on the Elwha River (Lake Aldwell), even though it was farther & slower to get to. And Mills had more regulations and restrictions, because it was within Olympic National Park, while the lower lake & dam were entirely outside the Park, and in legal multi-use (mostly State timber) lands. The settings of both are pretty & evocative (then, as now, with the lakes & dams gone); the abrupt plunging-hillside forested ‘shores’ (rather ‘harsh’; no beaches, only occasional small pull-outs) were comparable in both cases.
The main observabable difference with these two man-made lakes, is that at Mills the boat launch and little parking/camping area was at the dam, and the upper end of the lake was undeveloped. On Lake Aldwell, the launch and parking was tucked into the upper reaches of the lake, surrounded by dense forest and riverine channels, and the dam (with floating-boom approach-barriers) was at the far other end. For some reason, many folks seemed to rarely or never go to Aldwell, but were more familiar with Lake Mills.
At the far end of Lake Mills was once a small campground, which could also be reached using the short Upper Lake Mills Trail, from a small Upper Lake Mills Trailhead, on Whiskey Bend Road. In the mid 1960s it was possible to boat in to the campground, and there was only a limited delta-formation where the river entered the lake. But then came the 1967 Convulsion Canyon lanslide, which temporarily dammed the river about 4 miles upstream. Not long after that, the campground was no longer easily reached, as the delta had expanded greatly and grew up in dense thickets. It might have been washed out in 1967, or later; today the former camping area cannot be found; it may also be buried under subsequent layers of delta-sediments.
It was known for boaters to set up in the little campground, and then be joined later by family and friends who would drive to the trailhead and walk down the 0.4 mile trail (or vice versa). It will now be interesting to see how the general site evolves & stabilizes; it’s possible remnants of the delta will remain as flat sandy-gravelly benches that will make a nice new camping-setting. As of the end of 2014 and the beginning of 2015, the site is still in transition following the draining of the lake, and care should be taken to notice & avoid any unstable slopes and accumulations of deep mud. There could be a few years of rapid changes.