A drawdown of Lake Carlton was conducted to evaluate complete dewatering as a method for rehabilitation of a severely eutrophic lake. The water level was lowered 4.1 m exposing 80.7% of the bottom (29.4% sand and 51.3% organic sediments). Substantial germination and growth of terrestrial and aquatic vegetation occurred on the exposed bottom. Following refill a layer of consolidated sediments persisted over most of the area where organic sediments had been exposed. Most new vegetation was established at too great a water depth and died. A net gain in area covered by rooted aquatic vegetation persisted only 2 years after refill. No improvement in water quality was accomplished Increased standing crops of benthic invertebrates were only detected the winter following refill in areas where consolidation of organic sediments and extensive Typha growth occurred Black crappie populations increased following refill while brown bullheads were substantially increased only the 1st year after refill No substantial improvements were found for largemouth bass, bluegill, and redear sunfish populations.
