Subd. 1. Purpose. The purpose of this subsection is to establish requirements that are intended to contribute to the aesthetic environment of the city, enhance livability, and foster economic development by providing an attractive urban setting. This section is also intended to:
1. Protect, restore, preserve, and maintain the natural environment throughout the development process;
2. Enhance the appearance, character, health, safety, and welfare of the community;
3. Provide green spaces that can support the urban citywide tree canopy, wildlife, such as birds, in the urban environment;
4. Increase the compatibility of adjacent uses, minimize adverse impacts of noise, dust, debris, artificial light intrusions, activities, or impacts to adjacent or surrounding uses; and
5. Contribute to the green infrastructure of the city to reduce air pollutants, mitigate the urban heat island effect and storm water runoff issues.
Subd. 2. General Landscaping and Maintenance.
1. All exposed ground areas, including street boulevards (landscaped portion of right-of-way), and areas not devoted to off-street parking, drives, sidewalks, patios, or other such improvements shall be landscaped with sod, seed, shrubs, other ornamental landscape materials, and trees, except that trees shall not be planted in boulevard portions of the public right-of-way without approval from the City Engineer. Temporary erosion control measures shall be installed and maintained in proper working order until permanent erosion control measures are in place and functioning properly.
2. All landscaped areas shall be maintained by the property owner and kept neat, clear, and uncluttered. Any required plant material which is diseased or dies shall be replaced with like kind of the original size.
3. Plantings placed upon utility easements or public right-of-way are subject to removal if required for maintenance or improvement of the utility. In such cases, costs for removal and restoration shall be the responsibility of the property owner.
4. Final grades with a slope ratio of greater than three-to-one shall not be permitted without approval of the City Engineer and/or Building Official and shall contain approved treatment such as special seed mixtures or reforestation, terracing, or retaining walls. Berming used to provide required screening shall not have slopes in excess of three-to-one.
5. All new plants shall be guaranteed for 12 months from the time planting has been completed. All plants shall be alive, of good quality, and disease free at the end of the warranty period or be replaced. Any replacements shall be warranted for 12 months from the time of planting.
Subd. 3. Required Landscaping. Prior to approval of a building permit for a new structure or building addition, all uses shall be subject to the landscape provisions required herein.
1. Commercial, industrial, public, semi-public, institutional, multiple-family residential, attached residential, parking lots for five or more vehicles, and utility uses shall incorporate landscaping in conformance with the following standards and criteria.
a. Landscape design shall place emphasis upon the boundary or perimeter of the site at points adjoining the public right-of-way, other property, and the immediate perimeter of the structure(s).
b. Plant materials shall be appropriate for the site conditions (soils, climate, ground water, human-made irrigation, grading, and the like). To the extent possible, native drought resistant plant materials/trees shall be utilized.
c. Commercial, industrial, multiple-family, attached residential, public, semi-public, and institutional uses shall install irrigation systems to ensure survivability of landscape materials.
2. The trees fulfilling the requirements of this subsection shall be not less than 25% deciduous and not less than 25% coniferous. The minimum number of trees on any given site shall be as follows.
a. Single-Family Uses. Two trees per dwelling unit to be located in the front yard.
b. Two-Family, Townhouse, and Multiple-Family Uses. Residential structures containing two or more units shall contain, as a minimum, one tree per dwelling unit.
c. Non-Residential Uses. Non-residential uses shall contain at a minimum:
i. One tree per 1,000 square feet of gross building floor area; and
ii. One shrub per 300 square feet of gross building floor area.
d. Trees. An equivalent of up to 50% of the required number of trees may be substituted with the use of trees in combination with ornamental trees and/or shrubs. In such case, not less than three ornamental trees or ten shrubs shall be provided for each one required tree substituted.
3. Minimum Size. All plants must at least equal the following minimum size.
Table 28 | ||
Landscape | Balled and Burlapped | |
Table 28 | ||
Landscape | Balled and Burlapped | |
Evergreen trees | 6 feet | |
Ornamental trees | 2 inch diameter | |
Shade trees | 2.5 inch diameter | |
Tall shrubs/hedge material | 3-4 feet | |
Evergreen | 24-30 inch height | |
Low shrubs, deciduous | 24-30 inch height | |
Spreading evergreen | 18-24 inch height | |
4. Spacing.
a. Plant material centers shall not be located closer than three feet from a side property line or 12 feet from a front property line.
b. Where plant materials are planted in two or more rows, plantings shall be staggered in rows unless otherwise approved by the Zoning Administrator.
c. All tree and plant species shall be indigenous to the appropriate hardiness zone and physical characteristics of the site. Prohibited tree and plant species are identified in the following tables.
Table 29 | |
Shrubs | Scientific Name
|
Table 29 | |
Shrubs | Scientific Name
|
Barberry, common | Berberis vulgaris |
Barberry, Japanese | Berberis thunbergia |
Honeysuckle, Japanese | Lonicera japonica |
Honeysuckle, Tatarian | Lonicera tatarica |
Siberian peashrub | Caragana arborescens |
Winged burning bush | Euonymus alatus |
Table 30 | |
Trees | Scientific Name |
Table 30 | |
Trees | Scientific Name |
Amur maple | Acer ginnala |
Ash | Fraxinus spp. |
Black locust | Robinia pseudoacacia |
Boxelder | Acer negundo |
Buckthorn | Rhamnus spp. |
Cottonwood | Populus deltoides |
Elm, American | Ulmus americana |
Elm, Siberian | Ulmus pumila |
Ginkgo (female) | Ginkgo biloba |
Mulberry | Morass spp. |
Norway maple | Acer platanoides |
Russian olive | Eleagnus angustifolia |
5. Sod and Ground Cover. All areas not otherwise improved in accordance with approved site plans shall have a minimum depth of four inches of topsoil (black dirt consisting of not more than 35% sand) and be sodded, including boulevard areas located two feet behind the back of curb (for erosion control). Exceptions to these criteria may be approved by the Zoning Administrator as follows.
a. Seed may be provided in lieu of sod in any of the following cases:
i. Where irrigation is present;
ii. Where the seed is applied to future expansion areas as shown on approved plans;
iii. Where the seed is applied adjacent to natural areas or wetlands (seed mixture to be approved by the City Engineer); and
iv. Where the seed is applied to low maintenance areas alongside principal arterials (U.S. Highway 10) as defined by the Comprehensive Plan.
b. Undisturbed areas containing existing viable natural vegetation which can be maintained free of foreign and noxious plant materials.
c. Areas designated as open space or future expansion areas properly planted and maintained with prairie grass or wild flowers. Seed mixture to be approved by the City Engineer. Native prairie grass or wildflowers may be allowed in other areas subject to Zoning Administrator review and approval of a landscape plan.
d. Use of mulch materials such as bark, wood chips, and decorative block in support of shrubs and foundation plantings.
e. Storm water management ponds shall be seeded with native wetland species as approved by the City Engineer. The perimeter of “dry ponds” shall be landscaped with plants and wildflower seed/stock subject to the approval of the City Engineer.
f. To achieve ornamental grass, a minimum depth of four inches of topsoil (black dirt consisting of not more than 35% sand) shall be placed on the affected areas before seeding. A minimum depth of two inches of topsoil shall be placed on the affected areas before sodding. Ornamental grass shall be guaranteed for a full two years from the time planting is completed.
Subd. 4. Required Screening.
1. Non-Residential Uses. Where any non-residential use abuts property zoned for residential use, screening shall be provided along the boundary adjacent to the residential property. Screening shall also be provided where a non-residential use is across the street from a residential zone, but not on that side of a business, industry, or institutional building considered to be the front (as determined by the Zoning Administrator). The screening shall consist of a greenbelt strip, buffer yard, or other screening as provided for below.
a. A greenbelt planting strip shall consist of evergreen trees and/or deciduous trees and plants and shall be a minimum of ten feet in width and of a sufficient density to provide a visual screen and reasonable buffer. This planting strip shall be designed to provide visual screening to achieve a 75% opacity year-round and to a minimum height of six feet. The grade for determining height shall be the grade elevation of the building or use for which the screening is providing protection, unless otherwise established by the Zoning Administrator. The planting plan and type of plantings shall require the approval of the Zoning Administrator.
b. A fence or earth berm may also be installed, but not in lieu of the greenbelt plant materials. Earth berms may be used but shall also be planted with landscape screening materials. A fence shall be constructed of masonry, brick, steel, vinyl, or wood, except as otherwise provided herein. Such fence shall provide a solid screening effect and shall be a minimum of six feet in height. The grade for determining height shall be the grade elevation of the building or use for which the screening is providing protection, unless otherwise established by the Zoning Administrator. The design and materials used in constructing a required screen shall be subject to the approval of the Zoning Administrator.
2. Multiple-Family Uses. Where multiple-family buildings of three or more units abut property zoned or developed with a less dense residential use, the higher density residential use shall provide screening along all off-street parking and outdoor recreational activity areas and between multiple-family and single-family dwelling units to mitigate possible adverse impacts.
3. Buffer Yards. Buffer yards shall be located along lot lines for residential lots that abut major collector or arterial roads, railroad right-of-way, or overhead power lines.
a. Buffer Yard Requirements. Except as may be approved by the City Council, lots which border major collector, arterial street, overhead power lines, or railroad right-of-way shall provide a minimum 20-foot buffer yard in addition to the required lot width and depth requirements of the underlying zoning district, to screen homes from said streets, power lines, or railroad right-of-way. With the exception of those lots which are located adjacent to power lines or railroad right-of-way, buffer yards shall be maintained.
b. Buffer Yard Landscape Design Standards.
i. Plantings. All designated buffer yards must be seeded or sodded except in areas of steep slopes where natural vegetation is acceptable, and planted with trees and shrubs as approved by the Zoning Administrator. All plantings within designated buffer yards shall adhere to the following.
(a) Deciduous shrubs shall not be planted more than four feet on center, and/or evergreen shrubs shall not be planted more than three feet on center.
(b) Deciduous trees intended for screening shall be planted not more than 40 feet apart. Evergreen trees intended for screening shall be planted not more than 15 feet apart.
ii. Accessory Structures. Accessory buildings shall not be located within designated buffer yards.
iii. Earth Berms. Earth berms within designated buffer yards:
(a) Shall contain no less than four inches of topsoil; and
(b) Landscaping proposed in conjunction with berms shall be planted in a manner that does not result in a single row of plants along the top of the berm. Landscaping shall be grouped and provided to accomplish visual interest as well as screening.
Subd. 5. Financial Guarantee. A financial guarantee consistent with Section 1109 shall be received prior to the issuance of any building permit or permit for land alteration.