Franklin Lakes City Zoning Code
ARTICLE XVII
Protection of Critical Slope Areas
§ 300-129 Purpose.
The purpose of this article is to preserve critical slope areas in the Borough of Franklin Lakes. These regulations are necessary to minimize the adverse impacts commonly associated with disturbance of steeply sloped areas, which are defined for the purposes of this chapter as a slope of minimally 15%. Development on grades of 15% or greater generally requires additional safeguards against erosion, and other conditions such as siltation, surface water runoff and pollution of potable water supplies. The most appropriate method of alleviating such conditions is through the regulation of disturbance to soil and vegetation in critical slope areas. Such regulation promotes the public health, safety and welfare of Franklin Lakes.
§ 300-130 Definitions.
The following definitions are applicable to this article:
Land where the grade is 15% or greater.
Any alteration or change to the natural terrain (including soil and vegetation). This term includes any activity involving grading or filling of a site, but does not include restoration or stabilization of an existing condition.
An elevated deposit of soil, rock or other materials either constructed or natural.
The percent of rise or descent of a sloping surface. For example, a grade of 15% corresponds to a fifteen-foot vertical change in elevation for every 100 feet of horizontal distance. (Refer to accompanying slope diagram for further clarification.)[1]
Grasses or other vegetation used in the stabilization of soils.
A structure constructed and erected between lands of different elevations to protect structures and/or to prevent erosion, and which is minimally four feet in height.
The deviation of a surface from the horizontal, usually expressed in percent.
[1]
Editor's Note: The slope diagram is on file in the Clerk's office.
§ 300-131 Steep slope identification and review criteria.
All applications for minor and major subdivision or site plan approval, or for a permit for construction, grading or clearing of any lot, except as otherwise provided in the definition of "disturbance" herein or exempted in this chapter, shall be evaluated for the presence of critical slope areas.
A.
Slope categories. The applicant shall prepare and submit a slope analysis for the entire site (including proposed roadways and common areas), and each proposed or existing lot. The property shall be evaluated to determine the presence of critical slope areas in the following categories:
Table 1 Slope Analysis Categories | ||
|---|---|---|
Slope Category | Percent Grade | |
1 | 15 to 19.99% | |
2 | 20 to 24.99% | |
3 | 25% or greater | |
B.
Slope analysis. The slope categories shall be identified on a plan drawn at a scale as required by the Borough's site plan or subdivision submission requirements.[1] It shall show the existing and proposed topographic contours at two-foot intervals and delineate the categories of critical slope areas as shown in Table 1 above. Existing contours shall be shown for a minimum distance of 25 feet beyond the property boundaries.
C.
Additional information required. The analysis provided by the applicant shall contain the following additional information:
(1)
It shall delineate and quantify those areas proposed for disturbance. The applicant shall provide a table showing the calculation of disturbed area in square feet and as a percent of the lot area, for each proposed lot.
(2)
It shall identify soil types present on the property, with specific reference to highly erodible soils as identified by the United States Department of Agriculture Soil Conservation Service.
(3)
Details on how the proposed construction will minimize adverse impacts upon the existing natural features of the lot shall be provided.
(4)
Plans and specifications for any retaining walls, steps, fences or other protective structures shall be provided.
§ 300-132 Regulations for development in steep slope areas.
A.
Maximum disturbed area.
(1)
No buildings, improvements or structures, including roads, driveways or parking areas shall be constructed, nor shall any displacement of soil or removal of vegetation occur within critical slope areas, except in accordance with the following schedule provided below in Table 2:
Table 2 Permitted Levels of Disturbance in | |||
|---|---|---|---|
Critical Slope Areas | |||
Slope Category | Percent Grade | Maximum Disturbed Area | |
1 | 15 to 19.99% | 50% of area in Slope Category 1 | |
2 | 20 to 24.99% | 45% of area in Slope Category 2 | |
3 | 25% or greater | 35% of area in Slope Category 3 | |
(2)
For a subdivision proposal, calculation of disturbed area is based on each individual lot, not the entire tract as a whole. Common areas are also subject to the maximum disturbed area. Roadways are exempt from the above limits of disturbed area, but are subject to the maximum permitted grade provisions of the Residential Site Improvement Standards.
B.
Limit of disturbance. A limit of disturbance line shall be established, in accordance with § 300-124B(1), definition of "no-disturbance area," of this chapter to preserve existing vegetation on each proposed lot.
C.
Variance required. Disturbance of steep slopes in an amount greater than indicated in Subsection A above shall require a variance.
D.
Exceptions. Irrespective of the above regulations, an applicant may regrade a steep sloped area, provided that in no event shall the applicant disturb or regrade more than 500 square feet of the tract to be developed. The Planning Board or Zoning Board of Adjustment may permit the disturbance and development of small isolated pockets of steep slopes, provided that the disturbance does not exceed 500 square feet.