§ 10.8 PROJECT BOUNDARY BUFFER YARD AND LANDSCAPING REQUIREMENTS.
   10.8.1   Definition and purpose of buffer yards.
      A.   A BUFFER is a specified land area, located parallel to and within the outer perimeter of a lot or parcel and extending to the lot or parcel boundary line, together with the planting and landscaping required on the land. A BUFFER may also contain, or be required to contain, a barrier such as a berm, fence, or wall, or combination thereof, where such additional screening is necessary to achieve the desired level of buffering between various land use activities. A BUFFER is not the same as the term “yard”.
         1.   Both the amount of land and the type and amount of planting specified for each buffer yard required by this Article are designed to ameliorate nuisances between adjacent land uses, or between a land use and a public road.
         2.   The planting units required of buffer yards have been calculated to ensure that they do, in fact, function to “buffer”.
      B.   Buffer yards shall be required to separate different land uses from each other, in order to:
         1.   Eliminate or minimize potential nuisances, such as dirt, litter, noise, glare of lights, signs, and unsightly buildings or parking areas; or
         2.   Provide spacing to reduce adverse impacts of noise, odor, or danger from fires or explosions.
   10.8.2   Location of buffer yards.
      A.   Buffer yards shall be located on the outer perimeter of a lot or parcel, extending to the lot or parcel boundary line.
      B.   Buffer yards shall not be located on any portion of an existing public or private street or right-of-way.
   10.8.3   Types of required buffers. There are two types of required buffers that may occur on any given development site, as follows.
      A.   Street buffers. Generally, a street buffer is located along the street(s) that border a development. The buffer requires a modest amount of landscaping, enhancing the “public” environment.
      B.   Project boundary buffers. Generally, a project boundary buffer is located around the sides and rear of a development. This buffer ensures an appropriate transition between uses. A buffer located around the perimeter of a nonresidential use is intended to protect adjoining land uses from noise, heat, dust, lights, and aesthetic impacts from more intense land uses.
   10.8.4   Permitted use of buffer area.
      A.   A buffer may be used for passive recreation and picnic facilities; and it may contain pedestrian, bike, or equestrian trials, provided that:
         1.   Minimal existing plant material is eliminated;
         2.   The total depth of the buffer is maintained; and
         3.   All other requirements of these regulations are met.
      B.   Other appurtenances which require high visibility and easy access, such as fire hydrants, public and emergency telephones, and mail boxes. No screening of such appurtenances is permitted.
      C.   A required buffer is encouraged to retain areas of native habitat and may incorporate water resources, including stormwater detention/retention facilities designed as a natural-appearing amenity. However, a minimum ten-foot contiguous width of the buffer shall be preserved as a planting area without stormwater facilities.
      D.   Ingress and egress to the proposed use, and utility lines and appurtenances, may cross the buffer provided they minimize the amount of buffer taken.
      E.   The buffer area may be included as part of the calculation of any required open space.
      F.   Identification signs may be located within a buffer as specifically permitted in the sign ordinance. The landscape buffer shall be designed to address visibility of permitted ground signs.
      G.   Lighting may be located within a buffer as specifically required in Article 9.5, Outdoor Lighting.
      H.   Other activities and development required by this ordinance or expressly authorized by the UDO Administrator.
   10.8.5   Prohibited use of buffer area.
      A.   Buffer area shall not be used for any building or use, accessory building or use, parking or loading area, storage area, or other principal or accessory uses except as specifically permitted in this ordinance.
   10.8.6   Planting in easements.
      A.   Where required plantings are located in easements, the utility provider shall be responsible for replacement of such required vegetation if maintenance or other utility requirements require their removal.
      B.   No trees shall be planted in wet retention ponds, drainage maintenance easement, or any utility maintenance easements.
      C.   Shrubs may be planted within easements, provided they are only within the outer three feet of the easement. No new trees may be planted in an easement.
      D.   Existing trees may remain in dry retention ponds provided that the natural grade is undisturbed to the tree line, they are a species adapted to seasonal flooding and the pond is adequately maintained.
   10.8.7   Determination of buffer requirements. To determine the type of buffer required between two adjoining lots or parcels, or between a lot or parcel and a street, the following procedure shall be followed:
      A.   Street buffers. Determine the appropriate street buffer based on Article 10.8.8.
      B.   Project boundary buffers. Identify the zoning districts/use of the subject parcel and all adjoining properties. Determine the buffer opacity class required on each boundary (or segment thereof) of the subject parcel. Refer to the minimum project boundary buffer table in Article 10.8.9.
   10.8.8   Street buffers. Street buffers shall be required and existing vegetation should be used to satisfy these planting requirements where possible (see Article 10.8.3). Berms constructed in accordance with Article 10.8.10.C, Berm with Vegetation, are encouraged as a component of any street buffer and the UDO Administrator may allow up to 50% reduction in the required buffer depth with a berm.
      A.   Measurements.
         1.   Street buffers shall be measured along a perpendicular line from the future right-of-way line determined during site and development plan review. Buffer depth averaging may be used in conformance with paragraph (5), below.
         2.   Required driveways may penetrate required street buffers.
         3.   Driveway widths (measured at the inside edge of the buffer) shall not be counted in the calculation of the plant material required.
         4.   Vehicular access easements shall not be treated as a street, but shall be buffered as a project boundary buffer outside the easement area. The buffer may be provided on either side of the easement.
         5.   While the buffer depth is normally calculated as parallel to the property line, design variations are allowed and are calculated on the average depth of the buffer per 100 feet of linear width measured along the property line. Minimum depth of buffer in any case shall not be less than 50% the required depth of the buffer chosen. Maximum depth shall not be more than 150% the required depth of the buffer chosen.
      B.   Collector or thoroughfare street buffers. All development located along either a collector or thoroughfare street shall be required to provide one of the following buffers along the entire street frontage:
         1.   Two canopy trees per 100 linear feet of property frontage, located within a 20-foot landscape buffer;
         2.   One canopy tree and two understory trees per 100 linear feet of property frontage, located within a 20-foot landscape buffer;
         3.   Under utility lines only, three understory trees per 100 linear feet of property frontage, located within a ten-foot landscape buffer. No trees under utility lines shall have a natural height over 25 feet; or
         4.   In all the above options, there shall also be 15 shrubs per 100 linear feet.
   10.8.9   Project boundary buffers.
      A.   Required project boundary buffer table.
         1.   Description.
            a.   The buffer standards in the table below address the opacity of the buffer that is required on the property boundary between zoning districts, and in some instances within a zoning district.
            b.   An opacity of 0.2 screens 20% of an object, and an opacity of 0.6 would screen 60% of the adjoining development during summer months after five years of growth.
         2.   Measurement. Project boundary buffers shall be measured along a perpendicular line from the lot line.
         3.   How to read the buffer table.
            a.   The required opacity of project boundary buffers is represented in the table below by two numbers (for example, .2/.6).
            b.   The second number represents the total required buffer opacity between any two properties.
            c.   Where the proposed project adjoins vacant property, the first number represents the applicant’s required buffer opacity.
            d.   Where the adjoining property is already developed with no buffer, the proposed project is responsible for providing the total required opacity (the second number).
            e.   Where the adjoining property is already developed with a partial buffer, the proposed project is responsible for providing the remaining opacity required.
            f.   A zero means no project boundary buffer is required.
 
Zoning District of Adjoining Property
Zoning District of Subject Property
R-20, R-15, R-10, EPUD
MR, CN
CLD, CI
R-20, R-15, R-10, EPUD
0/0
.2/.2
.4/.6
MR, CN
.2/.2
0/0
.2/.4
CLD, CI
.4/.6
.2/.4
0/0
NOTE: Wireless telecommunication towers shall require a buffer yard with an opacity of 0.8 regardless of their location (refer to Article 8.101).
 
   Example. A .2/.4 requires a 20% opaque buffer for property adjacent to vacant land or a 40% opaque buffer when adjacent to existing development. A .4/.4 requires a 40% opaque buffer for property adjacent to either vacant or developed land. A zero means no project boundary buffer is required.
      B.   Buffer alternatives. The table below shows the required buffer depth (average) and plantings required for a project boundary buffer to satisfy the required opacity. Existing vegetation should be used to satisfy these planting requirements where possible (see Article 10.9.2, Existing Vegetation).
 
Minimum Required Project Boundary Buffer
Buffer Depth and Plants Required per 100
Required Opacity
Alternative 1
Alternative 2
0.2
5 feet
1 canopy
7 shrubs
5 feet
2 understory
3 shrubs
0.4
10 feet
1 canopy
4 understory
15 shrubs
10 feet
1 canopy
5 understory
9 shrubs
0.6
15 feet
3 canopy
6 understory
25 shrubs
15 feet
4 canopy
4 understory
10 shrubs
0.8
25 feet
5 canopy
7 understory
25 shrubs
25 feet
4 canopy
10 understory
15 shrubs
 
   10.8.10   Walls, berms, and fences in buffers. Where walls, berms, or fences are built within any required buffer, they shall meet the following requirements.
      A.   Walls.
         1.   All walls, when located within a buffer, shall be planted along the exterior face of the wall with at least one upright shrub for every six feet of linear wall length. These shrubs may be counted towards meeting the opacity requirement for the buffer.
         2.   Where shrubs are planted adjacent to a wall, the minimum distance between the wall and the property line shall be four feet.
         3.   A finished side of the wall shall face off site.
         4.   The applicant shall be required to demonstrate provision for access and maintenance of landscaping and the wall structure at the time of landscape plan approval.
      B.   Fences.
         1.   Fencing shall comply with the height requirements outlined in Article 9.7.1.B.
         2.   No reduction in buffer width shall be provided based on the provision of a fence.
         3.   If fencing is used, required shrubs shall have a minimum height of three feet at initial planting, and shall be placed along the exterior face of the fence. At least one upright shrub shall be required for every six linear feet of fence length. Shrubs are not required for a security fence.
         4.   A finished side of the fence shall face off-site.
         5.   Fences shall be maintained in a structurally safe and attractive condition and with finished faces and plantings located towards the adjoining property.
      C.    Berm with vegetation.
         1.   The UDO Administrator may allow a reduction of up to 50% of the required buffer depth when a berm meeting these requirements is provided.
         2.   An earthen berm may be used in conjunction with planted vegetation provided that the combined height of the berm and planted vegetation shall be at least six feet.
         3.   The slope of the berm shall be stabilized with vegetation and no steeper than three to one. The height of the berm may not exceed six feet, with a level or rounded area on top of the berm. The berm shall be constructed of compacted earth.
         4.   Prior to issuance of a certificate of occupancy, berms shall be planted to ensure coverage by live plant material, including grass, within two years.
         5.   When berms are planned to be installed within required buffers, storm drainage plans submitted with the application shall be designed to anticipate a 100-year storm event.
(Ord. passed 2-3-2021)