Laserfiche WebLink
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
lot, width standards for rivers, other existing river management plans and programs as well as <br /> the existing structure setbacks for lake shoreland development were reviewed to assist in <br /> developing structure setback standards for rivers. These standards were then compared to the <br /> previously discussed management objectives (SUP#5). For Remote segments, a 200 foot <br /> setback form the Ordinary High Water Level (OHWL) is reasonable because it provides an <br /> adequate separation between the river and development, which will maintain the remote and <br /> undeveloped character for these types of segments. For Forested and Transition segments, a <br /> 150 foot OHWL setback is reasonable because development can be placed closer to the river <br /> while still achieving the objectives of recreational management and protecting wooded <br /> shoreland areas. For Agricultural,Urban and Tributary segments, the 100 foot OHWL <br /> setback is reasonable in unsewered areas because an adequate distance will remain between <br /> development and the river to enable installation or preservation and maintenance of <br /> vegetation which can intercept and filter surface water runoff from developed areas. On many <br /> transition, agricultural and tributary river and stream systems, the proposed structure setbacks <br /> will provide for a minimum of protection from the natural meandering and channel shifting <br /> characteristics of watercourses found in these areas. Additionally, for all of the above OHWL <br /> setbacks, the preservation of open space between the river and development is necessary to <br /> provide flexibility in the placement and design of on site sewage treatment facilities. <br /> Sewered areas of Remote, Forested and Transition segments are rare and it is reasonable not <br /> to reduce the OHWL setbacks, in order to maintain consistency throughout these classes and <br /> meet the previously stated management objectives. <br /> In sewered areas of Agriculture, Urban and Tributary segments an OHWL setback of 50 feet <br /> is reasonable since these areas are usually already highly developed and the preservation of <br /> open space for on site sewage treatment systems is not necessary. Further, a 50 foot OHWL <br /> setback will reasonably allow for installation or preservation and maintenance of vegetation <br /> or other facilities that can intercept precipitation and filter or reduce surface water runoff <br /> velocities in theses developed areas, thereby addressing water quality and quantity concerns. <br /> The setbacks from bluff tops for structures in all shoreland classes is needed and reasonable <br /> to protect bluff tops from adverse environmental impacts of development and construction <br /> activities. These impacts can be measured in both physical and aesthetic terms. Physically, <br /> development encroachment on bluff tops can lead to accelerated soil erosion and in some <br /> cases, slope failure. Aesthetically, development encroachment on bluff tops can compromise <br /> or eliminate the natural appearance of this topographical feature in shoreland areas.The 30 <br /> foot structure setback from the bluff top provides a minimum distance between the bluff top <br /> and the planned or proposed foundations, walls or eaves of a structure for the maneuvering of <br /> building materials during construction. Consequently, the preservation of soils can reduce or <br /> avoid erosion problems, and preservation and maintenance of vegetation can protect soils, <br /> screen development and maintain the natural appearance of bluff areas. Necessary shoreland <br /> alterations such as clearing of vegetation to accommodate structures can be conducted within <br /> the first 10 feet waterward of the bluff top setback area until the bluff impact zone is <br /> encountered, which is defined as being 20 feet from the top of the bluff and the whole bluff. <br /> (i.e., 20 feet plus 10 feet= 30 feet, the width of the bluff setback area). It is noted for clarity <br /> that the bluff impact zone is established for preservation and management of shoreland <br /> vegetation and soils, and all structural development is excluded from this zone, except for <br /> stairways, lifts and landings. (see Item I of this subpart for stairways &lifts and see Item C <br /> of this Subpart and Subp. 4 of Part 6120.3300 for additional discussion of bluff impact <br /> zones). <br /> 62 <br />