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memo 11 of 14 FOR did not have access to this article at this time this review was conducted. The following is a summary found online from http: // 01521 .com /rm /00164rm- Cyanobacteria- lake - Siog.htm The study was performed to determine if motor boats could accelerate the rate at which eutrophication occurs in shallow lakes. Two lakes were examined and tested for pH, turbidity, and phosphorus concentrations: one with motor boat activity and one without. Results indicate that motor boat activity creates enough disturbance on the bottom sediment to release the stored phosphorus into the overlying water. The authors indicate that a 10hp motor boat mixes water down to a depth of 6 feet, increasing to 15 feet for a 50 hp motor. Certain water ski boats are significantly more powerful than this, reaching 300 hp. This studv found sediment release of phosphorus at Greater water depths with lower horsepower than the results from Beachler and Hill 2003. Asplund, T. R., and C. M. Cook. 1997. Effects of motorboats on submerged aquatic macrophytes. Lake and Reservoir Management 13(1):1. This study investigated the effect of motor boat activity on macrophyte growth in Lake Ripley, Wisconsin through motor boat exclusions. Four enclosures were built in two areas, characterized by light and heavy macrophyte growth, in water depths of 3 feet near high boat traffic areas. The enclosures were of two types, solid plastic (to exclude sediment resuspension from nearby areas) and plastic meshing as a control. They found that sediment scouring by boats may prevent plant establishment in shallow areas where macrophyte growth is previously low. However, in areas of heavy macrophyte growth, sediments were not as easily resuspended by motor boat activity. The authors recommend that no -wake restrictions be established durinG critical GrowinG periods, such as earlv summer. Yousef, Y. A., W. M. McLellon, and H. H. Zebuth. 1980. Changes in Phosphorus Concentrations Due to Mixing by Motorboats in Shallow Lakes. Water Research 14: 22. Water quality was measured at several stations where motor boat activity occurred and at one control station in 3 shallow lakes (average depth ranged from 6 to 13 feet) in Florida. Mixing of the water column in the study lakes was accomplished using boats with different horse - powered engines for 2 -6 hours in shallow and deep areas of the lake for 3 -4 consecutive days. Water samples were collected in the morning before motor boat activity began and immediately following motor boat activity from water depths of 0.5 in from the surface and 0.5 in from the bottom and composited prior to analysis of phosphorus, chlorophyll and turbidity. The percent increase in phosphorus concentration after motor boat activity at the mixing stations ranged from 16 — 73% of the morning phosphorus concentration prior to boat activity at the mixing stations. There was also observed increases in chlorophyll -a at the mixing stations following motor boat activity. No recommendations were Given. 3. What were the findings of the Lake Owasso Use Attainability Analysis and the internal and external phosphorus loads to Lake Owasso? Why not address the other (larger) loads first? Emmons & Olivier Resources, Inc. 651 Hale Ave N, Oakdale, MN 55128 p: 651.770.8448 f: 651.770.2552 www.eorinc.com