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Comments to GLWMO Board by Len Ferrington on 22 September 2011 I would like to thank the Board for this opportunity to comment on the potential "no wake, no motorized watercraft" clauses that are being considered for possible inclusion in the Third Generation Ten -Year Watershed Management Plan. As written, the clauses are obviously controversial, have served to arouse very passionate feeling both for and against their inclusion, and are clearly objected to by a wide range of stakeholders, as evidenced by the large number of persons signing an (petition against them. They also have strong potential to produce unanticipated recreational, esthetic and economic consequences. As a scientist working in areas of water quality assessment and management, I am aware of the scientific literature related to the role that disturbance of lake bottom sediments may have in terms of phosphorus dynamics in lakes. The literature provides several conflicting studies of the extent to which re- suspension may liberate phosphorus, and some of the studies are very context specific and may or may not be generalizable to conditions that exist within lakes of the GLWMO. However, my intention in presenting these comments to the Board is not intended to provide a view or judgment as to the scientific merits of past studies, but rather to summarize other management options that have been discussed and /or recommended by past studies, and are available to the Board for possible implementation to reduce phosphorus loadings in Lake Owasso. I would also like to provide my views of a temporal sequence for implementation of management options over the next decade, and to emphasize the necessity to do "a posteriori" evaluations for the impact of the implementation activities. The implementation activities available for reducing loading of phosphorus in Lake Owasso are (1) CIP in areas deemed to contribute the highest loads of phosphorus from the surrounding terrestrial landscape, (2) better enforcement of existing no -wake ordinances. (3) reduction and control of invasive weed species, in particular curly -leaf pondweed, with whole lake eradication techniques recently promoted in an experimental program by the MN DNR, (4) program to reduce carp populations via removal of large individuals and possibly developing targeted fishing programs for the public (5) possible alum treatments, and (6) consideration of hypolimnetic aeration. It is my recommendation that these activities should be considered for implementation in the priority sequence listed above, with simultaneous, or nearly simultaneous, implementation of activities 1 and 2, implementation of activities 3 and 4 as soon as realistic, and only moving to possible implementation of activities 5 and 6 if activities 1 -4 do not produce the desired results. After each implementation activity there should be a 1 or 2 year evaluation of their effect on SRP during summer months. CIP in areas deemed to contribute the highest external loading will require at least 2 -3 years to plan and implement on a scale large enough to have measurable results. These activities, followed by two years of assessment of storm water run -off quality, mean that as much as five years may have to pass before we can realistically measure the effectiveness of CIP. Combined with better enforcement of current no- wake ordinances, we could see reductions in SRP that are measurable in terms of Secchi disc readings, Chl -a and TP by 2014 or 2015. During the time that the CIP emphasis is starting and expanding, however, the Board should make concerted efforts to obtain funding and permission to initiate a comprehensive, whole -lake reduction and control program for invasive species of aquatic plants. Currently, the recommended duration of this type of program is 4 -5 years, based on the biology of reproduction of curley -leaf pondweed. If this program could be implemented as early as 2013, its effectiveness could be evaluated starting in 2017 or