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f 1220 Tonkawa Shoreline Alteration November 10,2004 Page 3 In the section titled Urban Area Policies for Natural Resource Management. Policy 2 states: “2. Retention of natural vegetation will limit the impact of urbanization as visible from the lake. Building heiglits will be limited to less than the typical tree height. Minimum green belts will be provided with prohibitions against clearcutting or excessive thinning of vegetation. Natural vegetation wilt be preserved on slopes. Retaining walls will be discouraged except when absolutely necessary to prevent erosion, in which case they will be screened with natural vegetation.” Li regards to the upper wall, the City Engineer has indicated that from an engineering standpoint the proposed plan is acceptable. However, from aji aesthetic standpoint, elimination of the upper wall will be less visually intrusive. The Engineer has indicated to me verbal ly that the upper wal 1 system could be eliminated as long as a 3:1 or flatter slope was maintained above the lower wall, and natural vegetation with a strong root system was established at that location. My basic issue with the project is loss of the natural grade of the shoreline, replacing it with the upper retaining wall that may not be strictly necessary, and replacing the natural vegetation with contrived plantings and a garden-like view rather than a natural look. A more natural look could could be accomplished by eliminating the upper wall and replacing it with a gently sloped hillside at a 3:1 or flatter slope. The primary area where excavation occurrcxl to lower the ‘hump ’ is between the two sets of mature black oaks shown on the recent survey. It is my belief that the slope previously was uni fonn between the bases of those two groupings of oaks, whereas after the grading it seems that just south of tire northern group is a significant cut (which the submitted proposal would reinforce with a wall) and then a flat area to the base of the southerly oak group. This area currently has an elevation of 936'-937‘, whereas our 1992 topography and the actual surveyed tree base elevations suggest it sliould be a gentle slope from elevation 939' at the north end to 936.6' at the south end. The wall and stairway perpendicular to the shoreline extending from the south end of the house, is of lesser concern to me but might be unnecessary if additional fill was broughtmtotaperlhc grade furtlier south. This wall will only be minimally visible from the lake. Applicants ’ cross section A1 - A2 is the primar>' area I would change if the intent is to re-establish the original topographic screening. It could rise from tlie bottom of the steps (937.0) toward tlie shoreline 14' to a point with elevation 938.0, then drop to the top of the lower wall (933.6) in a distance of approximately 18', for a final slope of 18:4.4 or about 4:1. The slope parallel with the shore should be uniform in a line between tlie two definitive oaks, and that line becomes the drauiage divide, llie only are;i of concern is at the north end where this grading will have to blend in witli the more precarious slopes remaining on the neighboring property. Conclusion: I believe a grading plan can be devised that substantially restores the original topography without resorting to an upper retaining wall, allowing for a more natural looking shoreline, allowing for replanting ofscreening and bank stabilization vegetation to reduce the visual impiict of the home ’s close proximity to the lake, and that is more in line with the City’s policies.