Woodcliff Lake City Zoning Code
ARTICLE XV
Protection of Critical Slope Areas
§ 380-106 Purpose.
The purpose of this article is to preserve critical slope areas in the Borough of Woodcliff Lake. 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 article 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 Woodcliff Lake.
§ 380-107 Definitions.
The following definitions are applicable to this article:
Land where the grade is 15% or greater.
Any interference, alteration or change to the natural terrain (including soil and vegetation or any other element of the environment). This term includes any activity involving the clearing of vegetation, grading or filling of a site but does not include maintenance or refurbishing of existing topographical or previously constructed conditions, or the installation of ground cover, gardens, shrubs or other vegetation that does not alter or change the natural terrain (including soil and vegetation) or any other element of the environment.
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 fifteen-percent grade 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 plants and landscaping grown to keep soil from being blown or washed away.
A structure constructed and erected between lands of different elevations to protect structures, create a horizontal surface for lawn or recreation and/or to prevent erosion.
The deviation of a surface from the horizontal, usually expressed in percent.
[1]
Editor's Note: The Slope Diagram is on file in the Borough offices.
§ 380-108 Steep slope identification and review criteria.
All applications for minor and major subdivision or site plan approval or for permit for construction, grading or clearing of any lot, unless not included within the definition of "disturbance" under this article or exempted herein in this chapter, shall be evaluated by the applicant for the presence of critical slope areas, as defined herein.
A.
Slope categories. Unless exempt, 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 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. It shall show the existing and proposed topographic contours at two-foot intervals within the subject property and delineate the categories of critical slope areas as shown in Table 1 above. Existing contours at ten-foot intervals 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 the location of all trees of eight inches in caliper or greater (measured three feet above the natural grade), and contiguous wooded areas, along with the proposed limits of disturbance.
(3)
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.
(4)
Details on how the proposed construction will minimize adverse impacts upon the existing natural features (including but not limited to ponds, vegetation and rock formations) of the lot shall be provided.
(5)
The location and details of swales, detention basins and other facilities for the disposition of all stormwater shall be provided.
(6)
The disposition and extent of topsoil to be removed or filled shall be indicated.
(7)
Plans and specifications for any retaining walls, steps, fences or other protective structures shall be provided.
(8)
Elevations and sections of structures and related improvements shall be provided.
§ 380-109 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% | 35% of area in Slope Category 1 | |
2 | 20% to 24.99% | 25% of area in Slope Category 2 | |
3 | 25% or greater | 15% 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 subject to the maximum disturbed area as well. Roadways are exempt from the above limits of disturbed area, but are subject to the maximum permitted grade provisions under local ordinance or the Residential Site Improvement Standards.
B.
Limit of disturbance. A limit of disturbance shall be established to preserve existing vegetation on each proposed lot.
§ 380-110 Exceptions.
A.
Activities not constituting a disturbance. The provisions of this chapter and article shall not apply where there is no disturbance as expressly defined in § 380-107 herein (but not as such term may be defined in some other portion of the Borough Code).
B.
Disturbances on minor slope areas. The Construction Code Official may permit the disturbance and development of steep slopes otherwise subject to the regulations under this chapter where the slope area does not exceed an area as follows:
[Amended 9-6-2005 by Ord. No. 05-10]
District | Maximum Area of Lot Occupied by Critical Slope Area (square feet) | |
|---|---|---|
R-15 District | 2,000 | |
R-22.5 District | 2,500 | |
ARHO District | 20,000 | |
R-30 District and all other districts | 3,000 |
NOTES: In the ARHO District, the provisions of § 380-10 of this chapter shall apply in computing lot area for the purpose of calculating maximum lot area occupied by critical slope. |
(1)
Required information. The applicant requesting the Construction Code Official to declare the disturbance excepted under this chapter based on minor slope areas shall, in the application for their construction or other type of permit, delineate on a plot plan or other survey all of the information required in § 380-108B above to provide the Construction Code Official all information necessary to determine the existence of a minor slope area. The Construction Code Official may waive this requirement if, after making a visual inspection, the Code Official is satisfied that the area in question qualifies as a minor slope area under this section, and the Construction Code Official shall make a note of such finding on the permit.
(2)
Referral to Borough Planning Board. The Borough Construction Code Official may deny the claimed exception where the official determines that such minor slope areas are adjacent to other steep slope areas, as defined herein, and that such an area, together with the applicant's slope area, would not qualify for an exception under the terms of this article. In that event, the Construction Code Official shall refer the application to the Planning Board, and the applicant shall supplement the permit application with all other information required under this chapter and shall submit same to the Planning Board.
(a)
Standard for review on referral. On a referral from the Construction Code Official under the provisions of this section, no permit shall be issued unless the Planning Board determines that the disturbance of the critical slope area is consistent with sound planning and promotes the goals and objectives of the Borough's Master Plan; would not substantially impair the purposes of this chapter and the Borough's land use ordinances; and would otherwise result in practical difficulties for the applicant. The Planning Board must also be satisfied through competent proof offered by the applicant that disturbance in the steep slope area that would otherwise qualify for an exception under this article would have no adverse impact upon the adjoining slope area if the excepted area was disturbed in accordance with this chapter. The burden of proof shall be on the applicant to prove this to the Board's satisfaction. This standard of proof shall only apply to applications referred to the Planning Board from the Construction Code Official in the event that it appears that a minor slope area is adjacent to another sloped area and, as a result thereof, the minor slope area exception of this section of this article does not apply. In the event that an applicant makes application to the Planning or Zoning Board for a variance from the terms of the prohibitions against disturbances in the critical slope areas under this article, the standards for variance review as promulgated under this chapter and as required under the Municipal Land Use Law (N.J.S.A. 40:55D-1 et seq.) shall apply.
§ 380-111 Protective measures.
Provision shall be made for any structure or protective measures that may be required for the protection of the public safety, including but not limited to retaining walls, embankments, head walls and fences.
A.
Erosion control ground cover. Proposed slopes between 2:1 and 3:1 (ratio of vertical distance to horizontal distance) shall require plant material and ground cover suitable for erosion control.
B.
Requirement for retaining walls. Proposed changes in grade in excess of 3:1 (ratio of vertical distance to horizontal distance) shall be supported by retaining walls or by erosion control ground cover in accordance with § 380-111A.
C.
Retaining walls. Retaining walls typically are necessary components for development in critical slope areas. Therefore the following regulations are established for retaining walls in critical slope areas:
(1)
Retaining walls shall not have any continuous exposed wall face in excess of three feet in height measured from the lowest elevation of the finished grade, except that age-restricted multiunit housing in the ARHO District shall be permitted to have retaining walls with wall faces up to six feet in height. If a fence is required atop a retaining wall, the height of the fence shall not be considered in measuring the height of the retaining wall.
[Amended 9-6-2005 by Ord. No. 05-10]
(2)
In any embankment which is constructed by the use of retaining walls, each wall shall also be subject to a maximum height limitation of three feet and shall be tiered at every three-foot interval of height.
(3)
Each tier shall be set back a minimum of three feet to provide for the placement of landscaping on the tier.
(4)
Plantings shall be required at each tier level (except the top level adjoining a lawn area) to minimize the appearance of the wall's height and enhance its aesthetics.
(5)
Retaining walls shall not be erected within five feet of a street right-of-way, side or rear property line and be constructed in such a way so as to enable the property owner to perform periodic maintenance and upkeep to the area between the retaining wall and the right of way, side or rear lot line.
(6)
Retaining walls shall be designed to provide for proper drainage.
(7)
The use of interlocking block materials for retaining wall construction is encouraged