§ 5.3. Critical areas and environmental performance standards.

5.3.1. Erosion and Sedimentation Control.

All developments shall comply with the provisions of applicable soil erosion and sedimentation control regulations (article 5 of chapter 5 of the town code of ordinances). Certification of compliance with or exemption from the requirements of such regulations shall be submitted to the town manager prior to issuance of any zoning compliance permit for the development. No engineering construction permit or building permit shall be issued until certification of the completion of control measures and facilities required for all associated land-disturbing activity has been submitted to the town manager.

5.3.2. Steep Slopes.

(a)

Purpose and Intent. The purpose of this section is to minimize the grading and site disturbance of steep slopes by restricting land disturbance on steep slopes, and by requiring special construction techniques for development on steep slopes. These provisions are intended to:

(1)

Protect water bodies (streams and lakes) and wetlands from the effects of erosion on water quality and water body integrity,

(2)

Protect the plant and animal habitat of steep slopes from the effects of land disturbance, and

(3)

Preserve the natural beauty and economic value of the town's wooded hillsides.

(b)

Definitions. For purposes of this section, "slope" means the ratio of elevation change to horizontal distance, expressed as a percentage. Slope is computed by dividing the vertical distance ("rise") by the horizontal distance ("run"), and multiplying the ratio by one hundred (100). A "steep slope" is equal to or steeper than fifteen (15) percent.

"Cut and fill slopes" include all slopes graded by excavating part of a higher area, raising the surface of a lower area, or combining the two (2) methods of construction.

(c)

Applicability.

(1)

For purposes of this section, a "steep slope" shall include only those areas of size four hundred (400) square feet or greater. Three (3) different categories of steep slopes are established in this section, as described in Table 5.3-1.

(2)

Steep slope regulations contained in this section shall not apply to single-family dwelling units or two-family/accessory apartment dwelling units on lots lawfully created prior to January 27, 2003, or lots created pursuant to a preliminary plat approved by the town manager prior to January 27, 2003.

(3)

Steep slope regulations contained in this section shall not apply to existing cut and fill slopes associated with roads, parking lots or driveways.

(d)

Contents of Application Requirements. The following information shall be provided for any application proposing development where the project area includes an area of steep slopes:

(1)

A slope and topographic map for both existing and proposed conditions based on a map depicting contours at an interval of two (2) feet or less. The map shall indicate, through cross-hatching or separate colors, all areas within each slope category described in Table 5.3-1, below.

(2)

The location of any existing swales, streams, or areas of concentrated flow.

(3)

A map showing current land use cover type or ground cover on steep slopes.

(4)

A map showing soil types for the whole site, and providing from the county soil survey the names of the soil types and depths to bedrock for each type.

(5)

Additional information may be required if steep slopes will be impacted by development.

(6)

Applications for subdivisions shall include a slope and topographic map for both existing and proposed conditions based on a map depicting contours at an interval of two (2) feet or less. The map shall indicate, through cross-hatching or separate colors, all areas within each slope category described in Table 5.3-1, below. Areas containing slopes of 4:1 (25%) or steeper shall be called out on recorded subdivision plats for single - and two-family development along with a note that reads "No more than twenty-five (25) percent of the total combined area of 4:1 (25%) or steeper shall be disturbed."

(e)

Cut and Fill Slope Requirements. All new cut and fill slopes must not be steeper than a 3:1 slope (33%). Steeper slopes may be conditionally approved by the Town Manager.

(f)

Disturbance limitations. No more than twenty-five (25) percent of the total combined area of 4:1 (25%) or steeper slopes shall be disturbed unless a variance is granted by the Board of Adjustment.

(g)

Construction Techniques.

(1)

All plans must show provisions for reducing and minimizing stormwater runoff during construction of steep slopes and cut and fill slopes.

(2)

All perimeter dikes, swales, ditches, perimeter slopes; all slopes 2:1 or steeper; all slopes between 2:1 and 3:1 and greater than ten (10) feet in length; and all slopes between 3:1 and 4:1 and greater than fifty (50) feet in length and all slopes steeper than 3:1 shall be provided temporary or permanent stabilization with ground cover sufficient to restrain erosion as soon as practicable but in any event within even (7) calendar days of any phase of grading.

(3)

All other disturbed areas shall be provided temporary or permanent stabilization with ground cover sufficient to restrain erosion as soon as practicable but in any event within fourteen (14) calendar days of termination or completion of any phase of grading.

(4)

When any given area of construction is completed, it must have a permanent, stabilizing ground cover applied within the specified time period above. If irrigation is not provided, then the exposed soil shall be planted with species which can survive without irrigation. Vegetative cover or any alternative cover (rock, masonry, etc.) shall be maintained in perpetuity.

Table 5.3-1: Slope Construction Restrictions and Requirements

Slope Category	Illustration	Development Restrictions
Less than 15% (approx. 7:1)		No additional application requirements, design requirements, construction requirements, or land disturbance limitations pursuant to this Section.
15% (7:1) or greater, but less than 25% (4:1)		See D. above for application requirements. See E. above for cut and fill slope requirements. See F. above for disturbance limitations. See G. above for construction techniques.
25% (4:1) or greater		See D. above for application requirements. See E. above for cut and fill slope requirements. See. G. above for construction techniques.

 

( Ord. No. 2015-11-23/O-8 , § III; Ord. No. 2016-03-21/O-1 , § 7