[HISTORY: Adopted by the Mayor and Council of the Borough of Riverdale 4-18-2005 by Ord. No. 4-2005. Amendments noted where applicable.]
As used in this chapter, the following terms shall have the meanings indicated:
- NONCRITICAL SLOPE OR AREA
- Those slopes less than 15%.
- PRECAUTIONARY SLOPE
- Those slopes between 15% and 25%.
- PROHIBITIVE SLOPE
- Those slopes greater than 25%.
- STEEP SLOPE
- Slopes 15% or greater.
All development and redevelopment activities, including stripping of vegetation, grading, or other soil disturbances, may occur without approval under this chapter only on noncritical areas of the tract or steep slope areas, provided that the development activity complies with the following provisions:
No area with prohibitive slopes shall be disturbed, developed, or redeveloped.
No area with precautionary slopes may be disturbed or developed without the applicant submitting sufficient evidence to provide the following:
Soil erosion, land disturbance, and other environmental concerns have been adequately addressed;
The applicant has submitted grading, drainage, and landscaping plans for the entire lot or tract of land to be developed, each in accordance with the requirements specified in § 145-5 herein, which plans confirm conformance with the aforementioned performance standards and which further confirm that the rate and velocity of the surface water runoff from the entire site which will result following completion of the proposed development shall not exceed that which currently exists in the predevelopment conditions. Certification by a professional engineer will be required stating that the standards contained herein have been met.
A precautionary slope with a minimum grade of at least 15% but not more than 20% may have a maximum disturbance area of no greater than 50%.
A precautionary slope with a minimum grade of at least 21% but not more than 25% may have a maximum distance area of no greater than 25%.
An applicant may seek relief from the requirements of these regulations by applying for variances to either the Planning Board or the Zoning Board of Adjustment, depending on which board has jurisdiction based on the provisions of the New Jersey Municipal Land Use Law.
The Town Engineer, when reviewing an application to disturb precautionary slopes or when reviewing an application for variance relief from the requirements of this chapter, shall submit a report to the Planning Board or Board of Adjustment for each application. The Planning Board or Board of Adjustment shall be guided by, but not limited to, the following performance standards:
The applicant shall demonstrate that the disturbance of the steep slope area is necessary for the proposed development of the subject tract or lot, and that such development is otherwise in accordance with the applicable ordinance provisions of the Borough of Riverdale.
The applicant shall demonstrate that the proposed development has utilized the noncritical areas of the tract to the extent reasonably practicable and that an attempt has been made to minimize the disturbance of the steep slope areas by limiting development to isolated areas of steep slopes.
The applicant shall demonstrate that appropriate revegetation and landscaping of the disturbed steep slope areas will be provided so as to adequately stabilize the slopes and enhance the attractiveness of the site, all in accordance with accepted soil conservation and stormwater management techniques as promulgated by the Borough Engineer.
The applicant shall demonstrate that the proposed disturbance of the steep slope area minimizes the impairment of the visual quality of the site and protects the higher elevations along hillsides, ridges, and mountain tops which create visual amenities.
The applicant shall also demonstrate that:
Any geologic disturbance, including blasting, cutting, or excavating, resulting from the development of a steep slope area will be satisfactorily mitigated; and
The cost of providing and maintaining public facilities and services to those portions of the site where steep slope areas to be disturbed will not be substantially increased as a result of such disturbance.
Any applicant proposing to disturb steep slopes in the Borough of Riverdale shall submit the following information to the Borough Engineer and to the Planning Board or the Zoning Board of Adjustment, as the case may be, and all submitted plans, details and calculations shall be prepared, signed and sealed by a New Jersey-licensed professional engineer:
A steep slope analysis, utilizing the best available topographical information, as determined by the Borough Engineer. The analysis shall be based on two-foot contour intervals or spot elevations if appropriate. Areas designated as steep slope areas shall be shaded and the amount of land area calculated. The analysis shall identify noncritical, precautionary, and prohibitive slopes.
A grading plan, which shall be prepared at a minimum scale of one inch equals 20 feet, shall include the following information in addition to all other applicable requirements of the Land Development Ordinance:
Plans showing the location of, and details for, all drainage devices, retaining walls, cribbing, dams, or other protective devices to be constructed and any existing or proposed swales, ditches, brooks or other drainage patterns;
Plans, profiles, cross sections and details of all retaining walls showing the height of each wall, the elevation at the top and bottom of each wall, the materials to be used, a profile and cross section of each wall, any proposed plantings, any safety barriers, the calculations of anticipated earth and hydrostatic pressures and surcharges and the calculations detailing the design of each wall; and
A map designating the maximum limits of clearing and disturbance.
Drainage plans and supporting computations for any storm drainage system shall be submitted, including the following information as may be required by the Borough Engineer:
All existing or proposed storm sewer lines within or adjacent to the tract showing the profile, size, and slope of the lines, the direction of flow, and the location of each catch basin, inlet, manhole, culvert, headwall, and utility line, including pipe sizes and grads;
A map drawn to scale (minimum one inch equals 100 feet) showing the contributing area to each inlet or cross drain;
The weighted runoff coefficient for each drainage area that was utilized in the submitted computations and a report by the design engineer containing the design criteria used, the alternates considered, the reasons for the final selections and the design calculations.
Landscaping plans, indicating the following information:
The proposed limits of disturbance of the subject site;
A general depiction of all existing vegetation within the area to be disturbed and a planting plan, including a planting schedule, for the plant material to be installed;
A specific identification within the area to be disturbed of all individual trees or groups of trees which have a caliper of eight inches or more measured three feet above the ground level, with an indication of which trees are to be removed.
Developments shall be exempt from the steep slope requirements of this chapter, as follows:
Development approvals issued pursuant to this chapter are to be considered an integral part of development approvals under the subdivision and site plan review process and do not relieve the applicant of the responsibility to secure required permits or approvals for activities regulated by other applicable codes, rules, acts or ordinances. In their interpretation and application, the provisions of this chapter shall be held to be the minimum requirements for the promotion of the public health, safety, general welfare, and the protection of water quality.