(A) Determining density or yield.
(1) Applicants shall have the option of estimating the legally permitted density on the basis of mathematical percentages and formulas contained in this subchapter, or on the basis of a yield plan. Such yield plans consist of conventional lot and street layouts, and must conform to the county’s regulations governing lot dimensions, land suitable for development (for example, not including wetlands, street area and parking). Although such plans shall be conceptual in nature, and are not intended to involve significant engineering cost, they must be realistic, and not show potential house sites or streets in areas that would not ordinarily be legally permitted in conventional layout.
(2) In order to prepare a realistic yield plan, applicants generally need to first map the conservation areas on their site. Typical yield plans would include, at minimum, basic topography, vegetation, location of potential wetlands, 100-year floodplain and soils as indicated in the county soil survey published by the USDA Natural Resource Conservation Service.
(3) On sites not served by public sewage or a centralized private sewage treatment facility, soil suitability for septic systems in the area to be developed shall be demonstrated, by methods approved by the County Health Department. This means information from soil survey, not on site soil boring.
(B) Minimum percentage of conservation areas. The minimum percentage of land that shall be designated as conservation, and protected from further subdivision through the recorded plat, shall be as specified in Table A:
(1) The following types of land classifications should be included in the conservation area:
(a) Large woodland tract possessing quality timber and classified forest;
(b) Wetlands, as defined by latest version of U.S. Army of Corps of Engineers, jurisdiction manual;
(c) Designated floodplain and/or alluvial soils;
(d) Land with slopes exceeding 25%;
(e) All lands as classified as prime soils, as defined by Natural Resource Conservation Service;
(f) Land under permanent easement prohibiting future development (including easements for drainage structures);
(g) Karst topography;
(h) Unique and natural areas as designated by Heritage Trust; and
(i) Riparian areas.
(2) All conservation area shall be restricted from further subdivision through a conservation easement, in a form acceptable to the county and duly recorded in the County Recorder’s office as part of the plat.
(C) Density bonus. Additional density may be allowed by the Plan Commission when one of the following public benefits is proposed:
(1) Development of a conservation subdivision: a density bonus will be granted for the development of the proposed subdivision by following the conservation subdivision design methods outlined in this subchapter and providing the minimum primary, secondary and buffer conservation areas required by the zoning district;
(2) Creation of an endowment for conservation area maintenance; and
(3) Implementation of density bonus: the Plan Commission may allow up to a 10% density bonus to generate additional income to the applicant for the sole purpose of endowing a permanent fund to offset continuing costs of maintaining open space and conservation land of the proposed subdivision.
(a) These density bonuses may be implemented by reducing the amount of total conservation area or by reducing the minimum lot area requirements by up to 10% or by a combination of these approaches at the discretion of the Plan Commission. In no case, shall the minimum required primary conservation area or buffer area be reduced to provide the density bonus. In most cases, this subchapter provides sufficient flexibility that the minimum conservation area goals can be met while still accommodating the density bonuses.
(b) The bonuses density factor found in Table B shall be applied to the gross developable area as calculated in division (A) above. In cases where the calculation indicates a fraction of a dwelling unit, the applicant may increase the number of dwelling units to the next larger number of full dwelling units.
(D) Location of conservation areas.
(1) The location of conservation areas conserved through compact residential development shall be consistent with the policies contained in the Comprehensive Plan, and with the recommendations contained in Designing Open Space Subdivisions: A Practical Step-by-Step Approach.
(2) Conservation areas shall be comprised of primary, secondary and buffer conservation areas. All lands within primary and buffer conservation areas are required to be protected by a permanent conservation easement, prohibiting further development and setting other standards safeguarding the site’s special resources from negative changes.
(a) Primary conservation areas. This category consist of wetlands, land within the 100-year floodplain, steep bluffs and karst topography. These sensitive lands are not considered to be buildable (for both conventional and conservation subdivisions).
(b) Buffer areas. A 100-foot greenway which separates the housing area from the other remaining conservation areas and is designated as permanently protected, however in the absence of primary conservation areas the buffer area can attribute.
(c) Secondary conservation areas.
1. This category is in addition to the primary and buffer conservation areas, and constitutes the balance of the remaining land that shall be designated and protected from further subdivision. Full density credit for land in this category will be as indicated for each zone in Table C so that the development potential is not reduced by this designation. Such density credit may be applied to other unconstrained parts of the site.
2. Although the locations of primary conservation areas are predetermined by the locations of floodplain, wetlands, steep slopes and soils subject to slumping, greater latitude exists in the designation of secondary conservation areas.
3. The location of the secondary conservation areas shall be guided by the maps and policies contained in the Comprehensive Plan, and shall typically include all or part of the following kinds of resources: mature woodlands, aquifer recharge areas, significant prime farmland, historic, archaeological or cultural features listed (or eligible to be listed) on national, state or county registers or inventories, and scenic views into the property from existing public roads. Secondary conservation areas, therefore, typically consist of upland forest, meadows, pastures and farm fields, part of the ecologically connected matrix of natural areas significant for wildlife habitat, and water quality protect.
(d) Interconnected conservation area network. As these policies are implemented, it is the intent that, where possible, the protected conservation areas in each new subdivision will eventually adjoin each other, ultimately forming an inter-connected network of conservation areas, across the county.
(E) Evaluation criteria.
(1) In evaluating the layout of lots and conservation areas, the layout of lots and conservation areas, the following criteria will be considered by the Planning Commission as indicating design appropriate to the natural, historic and cultural features, and meeting the purposed of this subchapter.
(2) Diversity and originality in lot layout shall be encouraged to achieve the best possible relationship between development and conservation areas.
(3) Accordingly, the Planning Commission shall evaluate proposals to determine whether the proposed conceptual preliminary plan:
(a) Protects and preserves all prime agricultural soils, floodplain, wetlands and steep slopes from clearing, grading, filing or construction (except as may be approved by the county for essential infrastructure);
(b) Preserves and maintains mature and/or unfragmented woodlands, existing fields, pastures and/or orchards, and creates sufficient buffer areas to minimize conflicts between residential and agricultural uses. For example, locating house lots and driveways within wooded areas, or edge of woods is generally recommended, with two exceptions. The first involves significant wildlife habitat or mature and/or unfragmented woodlands which raise an equal or greater preservation concern, as described in divisions (E)(3)(e) and (E)(3)(h) below. The second involves predominantly agricultural areas, where remnant tree groups provide the only natural areas for wildlife habitat;
(c) If development must be located on open fields or pastures because of greater constraints in all other parts of the site, dwellings should be sited on the least prime agricultural soils;
(d) Maintains or creates an upland buffer of natural native species vegetation of at least 100 feet in depth adjacent to wetlands and surface waters, including creeks, streams, springs, lakes and ponds;
(e) Designs around existing hedgerows and treelines between fields or meadows. Minimizes impacts on large woodlands (greater than five acres), especially those containing many mature trees or a significant wildlife habitat, or those not degraded by invasive vines. Also, woodlands of any size on highly erodible soils with slopes greater than 10% should be avoided. However, woodlands in poor condition with limited management potential can provide suitable locations for residential development. When any woodland is developed, greater care shall be taken to design disturbed areas (for buildings, roads, yards, septic disposal fields and the like) in locations where there are no large trees or obvious wildlife areas, to the fullest extent that is practicable;
(f) Leaves scenic views and vistas unblocked or interrupted, particularly as seen from public roadways. For example, in open agrarian landscapes, a deep no-build, no-plant buffer is recommended along the public roadway where those views or vistas are prominent or locally significant. In wooded areas where the sense of enclosure is a feature that should be maintained, a deep no-build, no-cut buffer should be respected, to preserve existing vegetation;
(g) Protects wildlife habitat areas of species listed as endangered, threatened, or of special concern by the Indiana Department of Natural Resources and/or the U.S. Environmental Protection Agency;
(h) Designs around and places consideration of sites of historic, archaeological or cultural value, and their environs, insofar as needed to safeguard the character of the future, including stone walls, spring houses, barn foundations, cellar holes, earthworks, burial grounds and the like;
(i) Protects rural roadside character and improves public safety and vehicular carrying capacity by avoiding development fronting onto existing public roads. Establishes buffer zones along the scenic corridor of rural roads with historic buildings, stone walls and the like;
(j) Landscapes common areas (such as community greens), cul-de-sac islands and both sides of new streets with native shade trees specie and flowering shrubs with high wildlife conservation values;
(k) Provides actives recreation areas in suitable locations offering convenient access by residents, and adequately screened from nearby house lots;
(l) Includes a pedestrian circulation system designed to assure that pedestrians can walk safely and easily on the site, between properties and activities or special features within the neighborhood conservation system. Trails, which in turn should link with potential conservation areas on adjoining undeveloped parcels (or with existing conservation areas on adjoining developed parcels, where applicable); and
(m) Provides conservation areas that are reasonably contiguous, and whose configuration is in accordance with the guidelines contained in the Design and Management Handbook for Preservation Areas, produced by the Natural Lands Trust. For example, fragmentation of conservation areas should be minimized so that these resource areas are not divided into numerous small parcels located in various parts of the development. To the greatest extent practicable, this land shall be designed as a single block with logical, straightforward boundaries. Long thin strips of conservation land shall be avoided, unless the conservation future is linear or unless such configuration is necessary to connect with other streams or trails. The conservation areas shall generally abut existing or potential conservation areas land on adjacent parcels, and shall be designed as part of larger contiguous and integrated greenway system, as per the policies in the goal, objectives and strategies the County Comprehensive Plan.
(Ord. 1999-4-19, passed 4-19-1999)