SUBSTITUTE ORDINANCE NO. BL2008-328

An Ordinance amending Chapters 17.24 of Title 17 of the Metropolitan Code, Zoning Regulations, to make the tree density requirements applicable to certain residential development, all of which is more particularly described herein (Proposal No. 2008Z-089T).

An Ordinance amending Chapters 17.24 of Title 17 of the Metropolitan Code, Zoning Regulations, to make the tree density requirements applicable to certain residential development, all of which is more particularly described herein.

BE IT ENACTED BY THE COUNCIL OF THE METROPOLITAN GOVERNMENT OF NASHVILLE AND DAVIDSON COUNTY:

Section 1. That Section 17.24.050 of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended as follows:

1. By deleting subsection A in its entirety and substituting in lieu thereof the following new subsection A.:

“A. Improvements or repairs to interior and exterior features of existing structures, including the conversion of a non-residential building to residential use either in whole or in part, as provided by this title.”

2. By deleting subsection C. in its entirety.

Section 2. That Section 17.24.080, of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by deleting the provisions of subsection B. in their entirety and substituting in lieu thereof the following new provisions:

“B. Watering. All required landscaping, excluding trees planted or preserved on residential property in accordance with section 17.24.100 of this chapter, shall be watered by one of the following methods:
1. An underground sprinkler system;
2. An outside hose attachment within one hundred feet of all landscaping.”

Section 3. That Section 17.24.090, of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by adding the following provision at the end thereof:

“For purposes of this chapter, the term ‘protected tree’ means a tree with at least a six-inch diameter at breast height (DBH) that is selected to be saved or preserved for purposes of being counted toward the required tree density for the property.”

Section 4. That Section 17.24.100, of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by deleting the existing subsection B. in its entirety and substituting in lieu thereof the following new subsection B.:

“B. Tree density.
1. Each property, other than those residential properties provided for in subsection B.2. of this section, shall attain a tree density factor of at least fourteen units per acre using protected or replacement trees, or a combination of both.
2. Residential properties shall attain the following tree density factors:
a. Property within a single and/or two-family residential subdivision for which the preliminary site plan is filed with the planning commission after the date of enactment of this subsection B.2. shall attain a tree density factor of at least fourteen units per acre using protected or replacement trees, or a combination of both, excluding the area of the building lots. Proof of compliance with this requirement shall be provided prior to the release of any applicable public infrastructure bonds.
b. Requirements for individual single and two-family residential lots.
(i) Individual single and two-family lots, other than those lots zoned AG or AR2a, shall include at least one two-inch caliper tree for each thirty feet of lot frontage (or portion thereof), excluding alley frontage. Such trees must be chosen from the Forestry Recommended and Prohibited Tree and Shrub List, and shall be of a form and quality set out in the American Standard for Nursery Stock (ANSI Z60.1, latest edition).
(ii) Individual single and two-family lots on a cul-de-sac shall attain a tree density factor of at least two two-inch caliper trees for each thirty feet of lot frontage (or portion thereof). Such trees must be chosen from the Forestry Recommended and Prohibited Tree and Shrub List, and shall be of a form and quality set out in the American Standard for Nursery Stock (ANSI Z60.1, latest edition).
(iii) If the width of an individual single or two-family lot is less than twenty-five percent of the average lot depth, the lot shall attain a tree density factor of at least seven units per acre using protected or replacement trees, or both.
(iv) Proof of compliance with this subsection B.2.b. shall be provided prior to the issuance of a certificate of occupancy.
c. Alternative tree density requirements for single and two-family residential lots. In lieu of the requirements of subsection B.2.b. of this section, a home builder may petition the urban forester for credit for protecting existing trees on the building lot, provided that the overall tree density, including both replacement and protected trees, is not less than seven units per acre. Protected trees used to satisfy this requirement shall be protected according to section 17.24.110. Proof of compliance with this requirement shall be provided prior to the issuance of a certificate of occupancy.
3. Compliance with this subsection B. shall be calculated using gross acreage of the property but shall not include the following:
a. The portion of the land area currently or proposed to be covered by buildings;
b. The fenced area of any athletic field;
c. The area of a lake or pond which is covered by water year round;
d. Semi-trailer and tractor-trailer service areas, semi-trailer and tractor-trailer drive aisles, and semi-trailer and tractor-trailer parking and loading areas; and
e. Open areas of golf facilities.
Protected and replacement trees shall contribute toward the tree density.
4. Tree density shall be calculated according to the following schedules.

Protected Tree Schedule

UNITS represents basal area
DBH refers to diameter at breast height

  DBH   

UNITS   

DBH   

UNITS   

DBH   

UNITS   

DBH   

UNITS   

6   

1.2   

20   

4.3   

34   

10.5   

48   

26.1   

8   

1.4   

22   

4.9   

36   

11.7   

50   

28.3   

10   

1.6   

24   

5.7   

38   

12.9   

52   

30.5   

12   

1.8   

26   

6.6   

40   

18.4   

54   

32.8   

14   

2.1   

28   

7.5   

42   

20.2   

56   

35.2   

16   

2.4   

30   

8.4   

44   

22.1   

58   

37.7   

18   

2.8   

32   

9.4   

46   

24.1   

60   

40.3   

Note 1: For single and two-family residential development, a 1.0 UNITS credit shall be given for each protected tree having a 4-inch DBH

Replacement Tree Schedule

UNITS represents basal area
CAL refers to caliper size (a tree’s diameter measured six inches from the top of the root ball)

  CAL   

UNITS   

CAL   

UNITS   

CAL   

UNITS   

CAL   

UNITS   

2   

0.5   

5   

0.9   

8   

1.3   

11   

1.9   

3   

0.6   

6   

1.0   

9   

1.5   

12   

2.1   

4   

0.7   

7   

1.2   

10   

1.7   

14   

2.3   

Section 5. That Section 17.24.020 of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by deleting the phrase “Section 17.24.030, Exceptions”, and substituting in lieu thereof the phrase “Section 17.24.050, Exceptions”.

Section 6. That Section 17.24.100 of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by adding the following provision at the end of subsection H.:

“Notwithstanding the foregoing provision of this subsection to the contrary, there is no requirement that a replacement tree planted for credit be replaced if the tree dies as a result of a natural disaster or other act of God. For purposes of this section, ‘natural disaster’ shall not include drought.”

Section 7. That Section 17.24.100 of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by amending the first sentence of subsection F. by adding after the phrase “Subdivision developments”, the phrase “, other than single and two-family residential subdivisions required to meet the tree density requirements of subsection B. of this section,”.

Section 8. That Section 17.24.110 of the Code of The Metropolitan Government of Nashville and Davidson County, Zoning Regulations, is hereby amended by adding the following new subsection G.:

“G. Trees destroyed by natural disaster. There is no requirement that a protected tree designated to remain be replaced if the tree dies as a result of a natural disaster or other act of God, including a drought. For purposes of this subsection, ‘drought’ means a prolonged period of dryness that has caused extensive damage to, or prevented the successful growth of, crops within the Middle Tennessee area.”

Section 9. This Ordinance shall take effect five (5) days from and 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: Megan Barry, Mike Jameson, Vivian Wilhoite

LEGISLATIVE HISTORY

Introduced: October 7, 2008
Passed First Reading: October 7, 2008
Referred to: Planning Commission - Approved 8-0
(October 23, 2008)
Planning & Zoning Committee
Deferred to December 2, 2008: November 6, 2008
Deferred to January 20, 2009: December 2, 2008
Substitute Introduced: January 20, 2009
Passed Second Reading: January 20, 2009
Passed Third Reading: February 3, 2009
Approved: February 10, 2009
By:
Effective: February 12, 2009