1.   
   1. 1.
      HS Overlay District. Except as provided in Subsection C., Exceptions, the regulations of this section apply to all development (including tree removal) proposed within areas of land that have a slope of 20 percent or greater, are mapped as a Developmentally Sensitive Area, DSA, on the Kenton County Comprehensive Plan, or are mapped within the boundaries of an HS overlay district, as shown on the official district map.
   2. 2.
      Permits Required. Review of a development in a Hillside Stability (HS) overlay shall be completed according to the provisions in Sec. 07.21.9, Zoning Permit. The Zoning Permit review will be completed in consultation with the Covington Urban Forester and the City Civil Engineer. 
   3. 3.
      Excavation and Tree Cutting. No excavation, removal, or placement of any soil, foundation placement, or construction of buildings or structures of any nature or the cutting of trees more than eight inches in diameter at Diameter Breast Height (DBH) may occur without compliance with this Section and Sec. 04.12.3, Tree Preservation. 
   4. 4.
      Land Characteristics. The HS secondary district is appropriate for those areas of the City that have physical characteristics limiting development (Developmentally Sensitive Areas, DSA, in the Kenton County Comprehensive Plan) and hillside slopes of 20 percent or greater, so that development occurs in a manner that minimizes the adverse environmental and visual impacts associated with drainage, erosion, earth movement, and vegetation removal.

3. C.
   Exceptions. The following types of development are exempt from the provisions of this Section:

   1. 1.
      Roof, gutter, and chimney repair or replacement;
   2. 2.
      Interior alterations and repairs;
   3. 3.
      Construction of public utilities in the public right-of-way;
   4. 4.
      Development for compliance with retroactive provisions of the Covington Building Code; and
   5. 5.
      Development necessary to ensure the immediate public health or safety as required by an administrative body.
4. D.
   Restoration Bond Required. When, in the opinion of appropriate local officials, the termination before completion of a proposed excavation or fill operation would create an actual or potential hazard to the public, prior to the issuance of a permit, the owner shall be required to post a bond in an amount as determined by the local officials sufficient to cover the estimated cost of restoration of the site or completion of the operation (whichever is greater), plus an additional 15% for contingencies.
5. E.
   Standards.

   1. 1.
      General.

      1. a.
         In addition to the information required for a complete application per Sec. 07.20.5, Completeness, an application for applicable work in a Hillside Stability (HS) overlay shall address the following elements:

         1. 1.
            Preservation of existing topography;
         2. 2.
            Preservation and protection of natural features during the course of the construction;
         3. 3.
            The location of landslide prone areas and geotechnical hazards as determined by a geotechnical report;
         4. 4.
            Stormwater runoff;
         5. 5.
            Pedestrian, bicycle, and vehicular circulation and how it relates to existing contours; and
         6. 6.
            Preservation of the maximum amount of existing non-invasive vegetation.
      2. b.
         Disturbance to existing topographical features and native vegetation shall be minimized. Development shall be designed to fit into the hillside rather than altering existing topography to create a “flat land” type of development.
      3. c.
         Stormwater runoff, including from impervious surfaces, shall be collected and managed within the development site or transported from the site. Stormwater runoff shall not be directed onto adjacent private properties or the public right-of-way.
      4. d.
         Sidewalks, roads, and driveways shall be sited and constructed to be sensitive to existing contours.
      5. e.
         Slopes exposed in new development shall be landscaped to mitigate adverse safety and visual impacts created by hillside grading. Landscaping shall be installed and distributed around structures to improve soil conditions, reduce the risks of soil erosion, and soften, modify, and screen extensive retaining walls and cleared areas.
      6. f.
         Vegetation lines which convey the natural slope line of the hill shall be maintained, restored, and/or supplemented.
      7. g.
         Native and native-compatible trees, shrubs, and grasses should be planted to prevent erosion, minimize land slippage, and handle stormwater.
   2. 2.
      Contents of Geotechnical Report.

      1. a.
         Where required, a geotechnical investigation shall be made by a qualified geotechnical civil engineer indicating that any structural or physical changes proposed in the area will be completed in a manner that will minimize hillside slippage or soil erosion.
      2. b.
         The report shall define results of subsurface investigation of the area under consideration, including test borings, laboratory tests, engineering tests, and a geological analysis.
      3. c.
         The permittee shall assume all liability for damages, personal injury, or property damage resulting from work performed by the permittee, or their agent under the permit, or resulting from failure of the permittee to perform each obligation under the permit. If any claim of liability is made against the City of Covington, its officers, employees or agents, the permittee shall defend, indemnify, and hold harmless from such claim.
   3. 3.
      Construction Techniques (Earthwork). Grading shall minimize disturbance to natural landforms; not destroy visual quality; and not create conditions that may result in landslides, slope failures, excessive erosion or drainage, or flooding. All earthwork required for proposed developments shall comply with the following:

      1. a.
         Grading.  The following techniques shall be used:

         1. 1.
            When grading operations are necessary, the smallest practical areas of land should be exposed at any one time during development and the length of exposure should be kept to the shortest practical amount of time;
         2. 2.
            Utilize contour grading;
         3. 3.
            Cut-and-fill slopes with curved configurations that reflect the surrounding topographical context;
         4. 4.
            Round the toe and top of slopes to avoid angular forms at the convergence of manufactured and natural slopes;
         5. 5.
            Vary cut-and-fill banks and drainage terraces to alleviate monotony and allow for naturalistic landscaping;
         6. 6.
            Utilize finished grades of 15 percent slope or less. Cut or filled slopes shall not exceed 25 percent unless:

            1. a.
               The applicant submits a geotechnical investigation report that certifies the safety and suitability or such slopes; and
            2. b.
               The applicant proposes the use of walls, terraces, or other methods at intervals of not less than 10 feet to create planting beds that will stabilize the slope, and such measures are approved in the geotechnical investigation report as sufficient to ensure the stability of the slope and ensure that such slope shall pose no significant risk of danger to any property or public improvements located on or off the proposed development site.
         7. 7.
             Avoid long linear slopes, except in cases where the natural slope configuration displays this type of form; and
         8. 8.
            Utilize berms at the top of slopes and other locations to screen, vary profile, and ensure drainage away from slopes.
         9. 9.

            Fill shall not be placed over trees, stumps, or other organic or unstable material. All fill shall be compacted only to the extent to provide stability of material and to prevent undesirable settlement. Proper benching and soil pore spacing shall be provided in accordance with the recommendations of a qualified geotechnical or soils engineer.

      2. b.

         Retaining Structures.

         1. 1.

            The use of retaining structures when they will significantly reduce grading and land disturbance is permitted.

         2. 2.
             The height of retaining walls shall be a maximum of eight feet. An applicant shall utilize a series of smaller or shorter retaining walls rather than one large retaining wall, provided that the series of walls can be built without excessive removal of non-invasive vegetation during construction.
         3. 3.
              Retaining structures shall be constructed and or faced in brick or stone.
   4. 4.

      Roads and Driveways. Design of roads, driveways, and other circulation elements shall comply with the following guidelines:

      1. a.

         Contours.

         1. 1.

            Roadways and driveways shall be aligned to follow natural contours where feasible. Long stretches of straight road should be avoided by using gentle horizontal and vertical curves where feasible.

         2. 2.

            Roadways shall not be parallel to one another to avoid a “shelving” effect on hillsides.

      2. b.

         Grading.

         1. 1.

            Cul-de-sacs and loop streets that comply with the Subdivision Regulations in the RR, SR, RP, and REC districts and common driveways may be used to reduce the need to grade land. 

         2. 2.

            The Administrator may approve the following reductions to minimize the need for long driveways and necessary earth works:

            1. a.

               Required front or corner side setback may be reduced by a maximum of 20 percent;

            2. b.

               Required roadway width may be reduced by a maximum of 10 percent. 

   5. 5.

      Damage to Public and Private Infrastructure. A property owner shall take all necessary measures to protect public and private utilities and streets from drainage resulting from the development; including, when necessary, the repair, replacement, or relocation of such utilities. In the event of any damage resulting from the construction, completion, or operation of the development, the property owner shall be required to correct the damage.

6. F.

   Slope Restoration and Landscape Design

1.   
   1. 1.

      After construction is finished, slopes that are not vegetated shall be landscaped or restored to their natural ecosystem function to mitigate adverse impacts, such as hillside instability and uninteresting landscapes.

   2. 2.

      Restoration practices include dense plantings of trees and shrubs at a scale of 500 whips per acre in uncompacted soil (preferably not fill). Species selection will be dependent on the soil type/moisture and sun exposure. Restoration should be designed to include a diverse mix of native species. In addition to trees and shrubs a ground cover seeding of native forbs and grasses shall be applied to quickly stabilize the soil. 

   3. 3.
       To ensure success of the restoration, the survivability of the tree and shrubs shall be assessed annually for three years past the installation period. Reports should be provided to the Urban Forester in late May of each monitoring year by an ISA-certified arborist or some other equivalent. The final goal shall be for the applicant to demonstrate 80 percent survivability of all replantings at the three-year post-planting stage. 
   4. 4.

      Trees should be planted in random clusters, not in rows, to complement the natural tree distribution. Row planting of trees along property lines and roads is discouraged.

   5. 5.

      To minimize the visual obtrusiveness of buildings, plantings that screen building edges and foundations are encouraged.

   6. 6.

      Existing vegetation should be taken into consideration when landscaping the developed area. New landscaping should be compatible with existing vegetation and the scenic character of the surrounding area.

   7. 7.

      When new development occurs near the crest of a hill, the crest’s natural appearance should be maintained by tree planting and other landscape measures.

(Ord. No. O-13-21, 09/28/2021)

Effective on: 10/6/2021