§ 5-4000. Net developable area.

A.

Purpose. .....The comprehensive plan establishes an overall goal "to preserve and improve environmental quality of the county utilizing measures which protect Isle of Wight's natural resources and environmentally sensitive lands and waters", consistent with both the Virginia Clean Water Act and the Federal Clean Water Act. In land development, one (1) effective way towards accomplishing this goal is to establish environmental performance standards to establish the suitability of land for development. Virginia's enabling statutes for planning and zoning support environmental performance standards as a rational basis for utilizing the development suitability process. This process provides a more logical approach to define and allocate land holding capacities and densities to individual properties based upon the land and its underlying physical, environmental, and geological influences.

B.

Applicability. .....The net developable area shall be used for determining the density and building coverage of development permitted on a particular parcel or area. This approach shall apply to all forms of land development, with the exception of the following:

1.

The RAC zoning district.

2.

Single-family lots subdivided and approved for development prior to the adoption of this ordinance.

3.

Single-family lots shown on a preliminary subdivision plat in compliance with the provisions of subsection 1-1014.B.

C.

Net developable area calculations.

1.

The percentage cited below of the total area of environmentally sensitive areas shall be removed from the total acreage of a parcel or area in order to derive the net developable area:

a.

Tidal wetlands: One hundred percent (100%).

b.

100-year floodplains: One hundred percent (100%).

c.

Resource protection areas, including the required one-hundred-foot buffer: One hundred percent (100%).

d.

Non-tidal wetland: Fifty percent (50%).

e.

Slopes in excess of fifteen percent (15%) but less than or equal to thirty percent (30%): Fifty percent (50%).

f.

Slopes in excess of thirty percent (30%): One hundred percent (100%).

Where environmentally sensitive areas overlap, the more restrictive environmentally sensitive area shall be used. In no case shall overlap be counted twice in the calculation of net developable area.

2.

In addition to the above features of a site, the total area of the easements or rights-of-way associated with a 150-KV or greater power transmission line or regional gas transmission line shall be removed from the total acreage in order to derive the net developable area.

3.

Twenty percent (20%) shall be subtracted from the calculated net developable acreage to allow for existing or planned public or private street rights-of-way, unless it can be demonstrated to the satisfaction of the zoning administrator that the proposed street rights-of-way in a development or subdivision will be less than twenty percent (20%) of the calculated net acreage.

4.

Required open space shall be calculated using gross acreage.

5.

All calculation of recreational space and landscaping requirements shall be based on the net developable area.

6.

No lot shall be designed, approved or employed for use in which an area more than thirty percent (30%) of the prescribed minimum lot area is comprised of one (1) or more of the environmentally sensitive areas cited in [paragraph] 1., above. This shall not apply to lots specifically created exclusively to preserve and maintain environmentally sensitive areas, as approved by the zoning administrator.

D.

Example of calculating net developable area. .....The following example is provided for illustrative purposes in calculating the net developable area in a typical subdivision, although this approach applies to all forms of development not specifically exempted:

Zoning district:	Suburban Estates (SE)
Maximum density allowed:	2 units net acre
Gross acres:	100 acres
Floodplains:	7 acres
Resource protection area:	4 acres
Slopes > 15% but < 30%:	5 acres
Slopes > 30%:	2 acres
Power line ROW:	3 acres
Computation of property's environmentally sensitive features:
Floodplains:	7 acres × 100% = 7 acres
Resource protection area:	4 acres × 100% = 4 acres
Slopes > 15% but < 30%:	5 acres × 50% = 2.5 acres
Slopes > 30%:	2 acres × 100% = 2 acres
Power line ROW:	3 acres × 100% = 3 acres
	TOTAL = 18.5 acres
Computation of net developable area for SE property:
Gross acreage of property:	100 acres
Less deduction for property features:	- 18.5 acres
Available acres:	81.5 acres
Less street rights-of-way (20% of net developable):	- 16.3 acres
Total net developable acres:	65.2 acres

 

Development capacity of SE property units per acre × 65.2 net developable acres = 130 units per acre

(7-7-05; 3-20-14; 9-17-15; 7-19-18; 11-15-18.)

(7-7-05; 3-20-14; 9-17-15; 7-19-18; 11-15-18.)