An ordinance to amend various sections of Title 17 of the Metropolitan Code of Laws, the Zoning Ordinance of the Metropolitan Government of Nashville and Davidson County, relative to the bulk standards and scenic landscape easements applicable to the AG, AR2a, R80, RS80, R40, and RS40 zoning districts in order to provide for significant protection of unique natural, cultural, and historical resources and adding applicable definitions (Proposal No 2006Z-014T).

WHEREAS, it is desirable for the Metropolitan Government of Nashville and Davidson County to protect unique natural, cultural, and historical resources;

WHEREAS, protection of these unique resources can be accomplished through grouping lots on the more buildable portions of a tract:

WHEREAS, it is important to provide for new development that contributes to community without detracting from neighboring properties;

NOW, THEREFORE, BE IT ENACTED BY THE COUNTY OF THE METROPOLITAN GOVERNMENT OF NASHVILLE AND DAVIDSON COUNTY:

SECTION 1. By amending Section 17.04.060.B "Definitions of general terms: General Terms" by adding "Conservation land" to the list of general terms in alphabetical order, and defining it as follows:
"Conservation Land" means the portion of undeveloped land within a conservation subdivision that has been designated, dedicated, reserved, or restricted in perpetuity from further development and is set aside under a conservation easement. Excluded from Conservation Land calculations is land to accommodate required subdivision infrastructure, including green infrastructure such as planting strips, street medians/islands, drainage fields for individual sewage disposal systems, and conventional stormwater management devices.. Conventional stormwater management devices are those designed to hold water for an extended period of time and require disturbance of the land in order to meet detention requirements.

SECTION 2. By amending Section 17.04.060.B "Definitions of general terms: General Terms" by adding "Conservation subdivision" to the list of general terms in alphabetical order, and defining it as follows:
"Conservation subdivision" means a residential development where at least 50 percent or more of the land area is designated as undivided, permanent open space or farmland, thereby permanently protecting agriculturally, environmentally, culturally, or historically significant areas within the tract. The subdivision is characterized by compact lots, common open space, and the preservation maintenance of natural, historical, and cultural resources. Conservation subdivisions are an alternative approach to the conventional lot-by-lot division of land in rural areas that spreads development throughout a parcel with little regard to impacts on the natural and cultural features of the area.

SECTION 3. By amending Chapter 17.12 "District Bulk Standards" by adding Conservation Subdivision Standards 17.12.120.
Section 17.12.120 Conservation Subdivision Standards
In order to provide for the flexibility to conserve at least 50 percent of a tract of land in its natural condition, lots in conservation subdivisions in the AG, AR2a, RS80, R80, RS40 and R40 zoning districts may be arranged subject to the following restrictions:
A. Minimum Area. The minimum area of a conservation subdivision shall be no less than ten times the minimum lot area for the base zoning district as established by Table 17.12.020A. The Planning Commission may permit a smaller minimum area provided that the applicant can demonstrate that the proposed Conservation Lands will provide a connection between unconnected, existing areas of protected open space or other protected areas and will not result in providing only narrow or isolated fragments of Conservation Lands, or that the conservation subdivision will insure protection of a unique natural, cultural or historical area.
B. Alternative Lot Sizes. Up to 50 percent of the tract may be proposed for the development of single-family lots that contain less land area than normally required by Table 17.12.020A of the Zoning Code for the associated zoning classification.
C. Lot Reductions. Lots may be reduced in area as indicated in Table 17.12.120 and further described in C.1 through 7 below. Utilization of reduced lot sizes as shown in Table 17.12.120 in a conservation subdivision shall result in the creation of Conservation Lands.
Table 17.12.120
Minimum Lot Size for Conservation Subdivisions

1. Any lot separated from an adjacent tract, development, or subdivision by 200 feet or more is not subject to a minimum lot size requirement.
2. The minimum lot size of any lot separated from an adjacent tract, development, or subdivision by 150 feet to less than 200 feet can be reduced in size in accordance with Table 17.12.120.
3. The minimum lot size of any lot separated from an adjacent tract, development, or subdivision by 100 feet to less than 150 feet can be reduced in size in accordance with Table 17.12.120.
4. The minimum lot size of any lot separated from an adjacent tract, development, or subdivision by 50 feet to less than 100 feet can be reduced in size in accordance with Table 17.12.120.
5. There is no minimum lot size reduction for a lot separated less than 50 feet from an adjacent tract, development, or subdivision except where permitted under Section 17.12.120.C(6).
6. If the lots in an adjacent tract, development, or subdivision are smaller than permitted by the base zone district for lots in the conservation subdivision, then the Planning Commission may permit the conservation subdivision lots to be of a comparable size to the adjacent lots in the tract, development, or subdivision.
7. The separation distance shall be measured from property line to property line.
D. Density. The determination of maximum lot yield shall be based upon dividing the gross land area by the minimum lot area of the base zone district.
E. Bulk Standards. The bulk standard requirements for all residential lots shall be those established by Chapter 17.12 for the zoning district that most closely resembles the actual lot sizes within a conservation subdivision unless explicitly established otherwise according to Section 17.12.120.F.
F. Alternative Bulk Standards. The Planning Commission may authorize the establishment of alternative bulk standards based on a finding that those standards would serve to enhance the general development concept of the conservation subdivision, would equal or exceed the standard design objectives of the conservation subdivision, and would not impair the reasonable long-term use of other adjacent properties in fulfillment of the land use policies of the general plan. Alternate bulk standards may be approved in lieu of the following provisions of this title for those portions of a conservation subdivision separated by a minimum of 200 feet from an adjacent tract, development, or subdivision:
1. The setback standards of Table 17.12.020.A;
2. The street setback standards for new streets of Section 17.12.030; and
3. The landscape buffer yard standards of Chapter 17.24.
G. Development in Hillside and Floodplain Areas. Standards for the development of single-family lots in hillside and floodplain areas shall be as set out in Chapter 17.28. (Ord. 2002-1015 § 1 (part), 2002; Amdt. 1 with Ord. 98-1268 § 1 (part), 1998; Ord. 96-555 § 3.8, 1997)

SECTION 4. By amending Section 17.24.070 "Scenic Landscape Easements" by adding the following provision:
C. Landscape buffer yards shall not be required in conservation subdivisions where a scenic easement required by Section 3-10.5 of the Subdivision Regulations extends 50 feet or greater beyond the right-of-way.

SECTION 5. BE IT FURTHER ENACTED, that this ordinance take effect immediately after its passage and such change be published in a newspaper of general circulation, the welfare of The Metropolitan Government of Nashville and Davidson County requiring it.

Sponsored by: David Briley, Brenda Gilmore