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5. What are the relati�'e effects on shoreline and shall�w w�ater bottoms of (i) environmental or �veather conditions vs. (ii) recreational bc�ating? Turbidity is affected by depth and basin shape, laek of aquatic plants, wind action, and boating. Relative contr�butions of boats vs. wind are hard to assess. Studies that address this issue are rare. A poster at the National Lake Conference (.Nov. 96) described a study done in the eastern US in which turbidity was measured along transects from shore to mid-lake at various times of the day, and boat traffic was counted; traffic was correlated with increased turbidity (TN). Other potential factors contributing to turbidity were identified by SEH as rough fish and inadequately-treated urban runoff. Most settling ponds work well to catch large materials that settle in 1-2 days but fine sediments may not be caught. About 60% of Owasso's turbidity is due to algae, and 40% to unknown cause(s), possibly a combination of factors. Wabasso receives flow from Owasso but is much clearer; its non-algal turbidity is low. It has much less boat traffic and a different depth and shape. Rough fish can migrate between Owasso and Wabasso (JSch); Owasso does not have an excess of rough fish. (carp and black bullhead) for a lake of its type (DZ). 6. Discuss wakes, turbulence, and botrom sediment disturbance as a function of craft type, huq tppe, speed, propulsion system, and type of boating activity•. Waves break when wave height = 80% of depth. Energy is lost as the wave breaks and then on the shoreline, and runup pulls loose sediments off the shore. Sustained wave action is correlated with shoreline damage (EM). Kinetic energy of waves is related to their size, not their source. Soil characteristics of the shore are critical: silt and clay are less erodable than sand or gravel (TP, EM). Slowing for no-wake zones can generate large wakes (JSch). Lake aeration by natural factors is far greater than that from boat or PWC operation (JSch). Basin shape and wind direction affect the amount of natural aeration (DZ). 7. What is the relative significance of factors affecting la}:e water quality and t��hat is the expected lifetime;.of Lake � Ow�asso? What is its trophic status? On a geological scale, lakes may last 10,000 yr. Human activity accelerates filling in of lakes, which might occur in 7-8 generations (DZ), A 50% reduction in the apparent supply of ground water eontributed to a 1988 order by the DNR Commissioner that lake augmentation (pumping) was a low priority use of ground water (TN). Maintenance of lake level through pumping is now prohibited except in extenuating and chronic circumstances (DZ); as for Snail lake (TN). The county has removed many pumping systems and will soon remove the well on N. Owasso (TN). 8. Do the water quali:t}' goals for Lake Owasso have any relevance to or impact on ��ater surface use regulati<7n? There would be changes in safety, in wave energy and erosion, and in plant disruption. More plant debris would wash up on shore, If "something" (e.g. no-wake buffer, watershed projects) is changed, an impact will eventually be perceptible, but effects are not rapid (DZ). The panel was unclear what regulations were meant here and preferred to answer #9. Also see paragraph on MPCA goals, �9. 9. Will changing the no-wake bu1'fer zone from 300' to 150' have any impact on water quality�, erosion, weeds, or algae? Will wide weed beds (� 150') be affected? GW explained that the primary regulation at issue is a change from 300' to 150' no-wake buffer. A change to 150' means the city can never retuxn to 300' (DZ). Enforceability was discussed: the sheriff thinks 150' is more enforceable and 150' in the SW end would allow > 1 boat there at a time (GW); 300' has not been practiced or enforced (SP). Boaters might adjust their non-compliance with no-wake buffers as drivers do to speed limits (PE), or non-compliance could reflect an unreasonable law (GV1�. Kim Elverum of the DNR said the number of boats on the lake has probably not increased in 10 yr (PE). Ability to use the lake is important; boats keep the lake open (DA). Access in the SW end is not a problem, it will be created either by boat use or herbicides. Mechanical harvesting per DNR 3