§ 155.070 STANDARDS FOR PROTECTED WATERWAYS AND ALL BUFFER AREAS.
   (A)   General rule. No land-disturbing activity, development, or subdivision of any type shall occur in a protected waterway or buffer area, except as expressly allowed in this subchapter and other applicable county, state, or federal laws and regulations. The county shall not approve any land-disturbing activity, development, or subdivision until the applicant obtains all other necessary county, state, and/or federal permits. All buffer areas shall remain in a vegetated, natural state and shall not be modified in any manner except as expressly allowed in this section. Plant material adequate for filtering surface drainage shall be maintained within all buffer areas.
   (B)   Permitted uses and activities in the 100-year floodplain. Any land disturbing activity, development, or subdivision in the 100-year floodplain shall demonstrate compliance with the county’s Floodplain Ordinance, as amended.
   (C)   Uses permitted in the type a buffer areas and the streamside buffer zone. Within a Type A buffer area and the streamside zone of a Type B buffer area, allowable uses and activities are restricted to:
      (1)   Public flood control structures;
      (2)   Utility rights-of-way (Type A buffer only);
      (3)   Pedestrian-only trails; and
      (4)   Road crossings, where permitted.
   (D)   Uses permitted in the middle buffer zone. Allowable uses and activities within the middle zone of a Type B buffer area are restricted to:
      (1)   Utility rights-of-way;
      (2)   Biking or hiking trails;
      (3)   Stormwater management and sediment control facilities approved by the MSD; and
      (4)   Recreational uses that entail no impervious surfaces, or are approved by the Planning Commission.
   (E)   Uses prohibited in the outer buffer zone. The following uses and activities are not allowed within the outer zone of a Type B buffer area:
      (1)   Septic systems; and
      (2)   Permanent structures or impervious surface coverage with a footprint of greater than 100 square feet with the exception of approved recreational trails.
   (F)   Wetlands and alternative Type B buffers. The first 25 feet of wetland and alternative buffers shall meet the use restrictions established for the streamside buffer zone (division (C) above). For buffers less than 50 feet in width, the balance of the buffer area shall meet the middle buffer zone restrictions (division (D) above). For buffers more than 50 feet in width, one-half the width outside the first 25 feet may be used in accordance with the middle buffer zone restrictions and one-half may be used in accordance with the outer buffer zone restrictions.
   (G)   Location of platted lots in buffers areas.
      (1)   (a)   Any lot contained within a preliminary subdivision plat and intended for development shall be platted outside Type A buffer areas and outside the streamside and middle zones of all Type B buffer areas.
         (b)   The prohibition on development lots in this section shall not preclude the designation of the buffer area as a tract of land within the preliminary and final plats related to such real property; provided there is a plat note on such preliminary and final plat that references that the buffer area is subject to the terms and conditions of this subchapter and that the buffer area tracts are clearly identified as non-buildable tracts.
      (2)   Note: The application of pesticides and herbicides within Type A and the first 75 feet of Type B buffer areas is strongly discouraged.
   (H)   Prohibited uses and activities in buffer areas. The following uses and activities are prohibited in all buffer areas because of their proven potential for water pollution:
      (1)   Storage of hazardous substances and fertilizers;
      (2)   Above or below ground petroleum storage facilities;
      (3)   Drain fields from on-site sewage disposal and treatment system (i.e., septic systems);
      (4)   Raised septic systems;
      (5)   Solid waste facilities, such as landfills and including junkyards;
      (6)   Confined animal feedlot operations;
      (7)   Subsurface discharges from a wastewater treatment plant;
      (8)   Land application of biosolids; and
      (9)   Filling and/or excavation activities other than those attendant to uses specifically authorized.
   (I)   Recreation, education, or scientific activities allowed. Structures and improvements for recreational, educational, or scientific activities, including, but not limited to, fishing access and wildlife management and viewing, may be permitted in a buffer area; provided, a management plan that establishes long-term protection of the buffer area is submitted with the final plat or plan and is approved by the county.
   (J)   Stream and buffer area crossings: roads, bridges, trails, and utilities. Roads, bridges, trails, and utilities are permitted in a buffer area and may cross the protected waterway, subject to the Planning Commission’s approval based on the recommendations of the Public Works and the DPDS and the MSD.
      (1)   The applicant shall restore any disturbance of the buffer area and protected waterway by re-grading and re-vegetation. See division (K) below for applicable standards. Provisions for restoration of the disturbed area shall be included in any development or subdivision agreement for the project with adequate security to guarantee that the restoration will be completed.
      (2)   The right-of-way shall be the minimum width necessary for installation, access, and maintenance.
      (3)   Access for maintenance of utilities in buffer areas should be at specific points rather than parallel to the utility corridor.
      (4)   The angle of any crossings shall be perpendicular to the protected waterway or buffer area in order to minimize clearing and other land disturbance, unless the Planning Commission finds, based on comments from the MSD, the Public Works Department, or the Planning Director, that a perpendicular alignment is not feasible.
      (5)   The number of road crossings shall be the minimum number necessary to provide for adequate transportation connections as required in this chapter.
      (6)   No more than one fairway crossing associated with a permitted golf course use shall be allowed for every 1,000 linear feet of buffer area.
      (7)   Trench crossings of rock streambeds visible through the water column or exposed on a seasonal basis shall be restored to a natural appearance using grouting techniques.
      (8)   Plans for the crossing submitted with the application shall identify the alignment of the crossing, the proposed construction techniques, the proposed construction and working easements, and mobilization, staging, and temporary disposal areas.
   (K)   Restoration. At the time of development, the following restoration standards shall be met.
      (1)   Restoration required to stabilize banks. Riparian vegetation shall be planted, as necessary, to stabilize the banks of a protected waterway within a buffer area. Where a bank is denuded of its vegetation due to erosion, slope failure, or similar occurrence, appropriate vegetation shall be planted to quickly establish a vegetative cover, and then replanted with riparian vegetation to ensure the long-term stabilization of the bank. Restoration plantings shall be selected from the MSD native species restoration specifications.
      (2)   Restoration of eroded banks required. Where stream bank erosion has occurred as a result of on-site development activities, riparian vegetation shall be planted to stabilize the stream bank unless the county determines such vegetation would be inadequate to re-stabilize the bank. In instances where the county determines that planting of riparian vegetation is inadequate to stabilize the stream bank, alternate methods of stabilization approved by the county shall be utilized.
      (3)   Other restoration allowed. Stream, stream bank, and vegetation restoration projects are allowed where the goal is to restore the protected waterway, wetlands, or buffer area to an ecologically healthy state, as approved by the MSD.
   (L)   Water quality monitoring allowed. Water quality monitoring and stream gauging are allowed within the protected waterway and buffer area, as approved by the DPDS or by the MSD.
   (M)   Tree and vegetation removal.
      (1)   Existing, healthy trees and vegetation within a buffer area shall be preserved.
      (2)   This provision shall not prohibit any of the following;
         (a)   Removal of dead or diseased trees/vegetation (provided a live root system stays intact);
         (b)   Removal of noxious weeds;
         (c)   Removal of non-native trees/vegetation that threaten native species growth or reintroduction;
         (d)   Removal of fallen trees, tree limbs, brush, and similar debris that accumulate naturally in river/stream beds and that impede river/stream flow;
         (e)   Removal of any other tree/vegetation that is a threat to the public health or safety; or
         (f)   Removal of trees as part of an approved plan for stream side recreation or access (for example, pedestrian trail) or as part of an approved utility or road construction project.
(LDC § 4.8.6)