A. Grading: Before the issuance of a building permit, a grading plan prepared and signed by a registered civil engineer shall be submitted to and approved by the engineering division. Grading plans shall, at a minimum, show the elevations of the natural ground at all lot corners, the finished grade at corners, the finished pad elevation, finished floor elevations, rates and directions of all drainage swales, elevation height of all retaining or perimeter walls and finished sidewalk elevations at all front lot lines, and existing topographic elevations and drainage direction one hundred feet (100') outside the boundary of proposed project area and/or map.
1. Minimum Slopes: The minimum grade of all drainage swales on parcels shall be 0.5 percent, unless approved differently by the town engineer.
2. Pad Elevation, Residential: The building pad elevation of residential parcels shall be established at a minimum of ten inches (10") above the design sidewalk elevation at the lowest point of the parcel. The finished floor elevation of slab floor houses shall be a minimum of sixteen inches (16") above the sidewalk elevation. The pad elevation of all residential parcels shall be established at least one foot (1') above the maximum water surface in an adjacent storm drain channel or the ponded surface in an adjacent sump for collection of storm drain waters. An exception may be allowed in the case of a proposed subdivision served by a storm drain pump station. The standards of this subsection shall apply to any building pad elevation, except where the requirements of the California building code (CBC) exceed these standards, in which case the requirements of the CBC shall apply. However, the town engineer may approve a waiver of these elevations where the pad elevation is protected from flooding or runoff from the public right of way.
3. Drainage Plan: No interparcel or "cross drainage" shall be allowed, except as authorized by the town engineer. Each parcel shall drain its own water to a public street, approved public or private drainage facility, or natural drainage course without passing through or across an adjacent parcel, except where a legal right exists (e.g., a drainage easement), and is authorized by the town engineer. No parcel shall drain water over the bank of a flood control channel.
4. Grading Practices: All grading within the town shall employ the best available management practices, as determined by the town engineer, to minimize erosion, sedimentation, and unnecessary grading.
5. Grading Exceptions: Specific exceptions to the above requirements may be authorized at the discretion of the town engineer.
6. Bonding: The town may require as a condition of approval that a bond be secured before any grading when the grading is proposed before recordation of the parcel or final map. This bond would be used to install landscaping and appropriate erosion control measures as needed if the subdivider abandons the project after grading occurs. All bonding shall be in compliance with section 9.96.040, "Improvement Agreements, Lien Agreements, And Securities", of this article 6.
7. Hillside Grading: If the subject property is within an area having a natural slope gradient of fifteen percent (15%) or greater, refer to chapter 9.20, "Hillside Overlay District", of this title for applicable procedures and standards.
B. Erosion And Sediment Control: A proposed subdivision shall be designed so that all grading incorporates appropriate erosion and sediment control measures. (Ord. 242, 9-3-2013)