[HISTORY: Adopted by the Township Board of the Township of Grosse Ile 8-11-1980 by Ord. No. 137 as Ch. 24 of the Grosse Ile Township Code; amended in its entirety 6-9-2003 by Ord. No. 03-10. Subsequent amendments noted where applicable.]
GENERAL REFERENCES124a Area of Allowed Retaining Walls
Building construction — See Ch. 40.
Certificates of occupancy — See Ch. 59.
Fences and walls — See Ch. 103.
Flood control — See Ch. 116.
Roads and driveways — See Ch. 205.
Subdivision control — See Ch. 238.
Wetlands and drainageways — See Ch. 275.
Zoning — See Ch. 285.
As used in this chapter, the following terms shall have the meanings indicated:
- The removal or movement of soil, sand, stone, gravel, or fill dirt except for common household gardening, farming, and general ground care.
- A deposit of soil or rock placed or replaced by people or machine which raises an existing elevation.
- FILL MATERIAL
- Soil, sand, gravel, clay, peat, debris and refuse, waste of any kind, or any other material which displaces soil or water or reduces water retention potential.
- Any stripping, excavating, filling, stockpiling or any combination thereof, and shall include the land in its excavated or filled condition.
- GRADING PERMIT
- A permit issued to authorize work to be performed under this chapter.
- RETAINING WALL
- A vertical or near vertical wall structure constructed of masonry, wood, concrete or other similar materials that forms a structural barrier that is above ground on one side and is used to retain and stabilize earth located on the other side of the wall. For the purpose of this chapter, the definition of "retaining walls" shall not include seawalls or riprap constructed in accordance with the waterfront provisions of Article 17 of the Zoning Ordinance or foundation walls that are part of a building.
Grading permit. Any person desirous of improving, grading, excavating, filling, or otherwise making any surface alterations on any property within the Township of Grosse Ile shall first obtain a grade permit from the Township Department of Community Development. Any improvement, grading, excavation, fill or other surface alteration shall be in accordance with the grade permit and the approved application filed for such permit. No permit shall be required for minor changes in the grade of improved property where the storm drainage pattern on the property is not altered by such minor grade changes.
Retaining walls. The construction of any retaining wall over one foot in height located within the minimum required front, side or rear yard, as specified in the Zoning Ordinance, shall require a permit under this chapter. The construction of any retaining wall over two feet in height located within the lot's building envelope, as specified by setbacks required in the Zoning Ordinance, shall require a permit under this chapter.
The permit fee shall be as established by the Township Board and shall be posted or made available at the Township's Department of Community Development.
A grade plan shall be submitted with an application for a grade permit where topographical information has not been previously submitted on a site plan or plat or is inadequate on the subject property. Prior to issuance of a grade permit, the grade plan shall be approved by the Township Engineer, provided that the construction, enlargement or alteration of any sea walls, boat wells, or fill in relation thereto, on the spillways or floodplains of any natural streams or watercourses shall be permitted only in accordance with the provisions of Chapter 285, Zoning. Grade plans may be included with a plot plan or may be submitted as a separate plan. Grade plans prepared by a registered engineer or surveyor shall be required when requested by the Department of Community Development.
Grade plans shall show the elevation of the grade at existing and proposed structures on the property and existing grade at the nearest side of structures on adjacent property. They shall also show sufficient existing and proposed elevations on both the property to be improved, including the four corners, and on as much of the adjacent property as is necessary in order to establish the proposed surface drainage pattern. All elevations shall be based on U.S. Coast and Geodetic Survey datum. Elevation and location of the bench mark which was used for determining the elevations shall be shown on the plan. Retaining walls shall be illustrated with construction details provided.
The final building grade permitted by the Township's grade permit shall be established and maintained at an elevation that will provide a minimum five-percent slope away from splash blocks at the building or house for a minimum distance of 10 feet, and the balance of the building or house site shall be graded to provide positive surface drainage from that point to the street, ditch or other drainagecourse. Where the distance between the house and the lot line is less than 10 feet, the slope and grading will be as approved by the Township Engineer.
Finished grades shall maintain relationship to existing topography to the maximum extent practical. Grades shall be maintained in relationship to adjacent properties such that there are not significant changes in grade from one lot to another that require the use of retaining walls between adjacent lots beyond what is permitted under this chapter. The existing watercourse on adjoining properties shall not be altered without prior approval of the owners thereof.
A grade plan drawn by a registered engineer or surveyor of any proposed subdivision showing the topography of the area to be platted and indicating the existing drainage pattern and the proposed surface drainage from each parcel or lot shall be submitted with the preliminary subdivision plat. Drainage easements shall be provided across private property where necessary for handling surface drainage from adjacent properties.
Grades for residential properties may be approved by the Township's Building Inspector after visual on-site inspection. Grades around large buildings, such as churches, schools, offices, businesses, parking lots, etc., shall be approved by the Township Engineer. Before final inspection is made and a certificate of occupancy is issued, the rough grading must be completed, allowing for bringing the premises up to grade by the addition of topsoil, sod, and other landscaping. Final grading shall be completed within one year after the certificate of occupancy is issued.
Retaining wall construction standards.
Relationship to grade. Retaining walls shall be utilized only where needed to stabilize steep slopes, establish grade for buildings and accessory structures, preserve grade around trees, wetlands or other natural features to be preserved or as part of a grading plan to establish positive drainage from a site. Retaining walls shall not be constructed in a manner that alters natural drainage between properties or creates the need for mechanical drainage systems.
Building materials. Retaining walls shall be constructed of stone, brick, interlocking decorative concrete block, wood or other similar quality material approved by the Building Inspector. The use of broken concrete for retaining walls shall not be permitted.
Building Code compliance. All retaining walls shall be constructed in accordance with the Building Code.
Site restoration. Upon the completion of the retaining wall, all areas above and below the retaining wall shall be planted with grass or other suitable living plant material, except where pavement or decks are provided.
Retaining walls within floodplains. Retaining walls shall be permitted to elevate building sites and accessory structures above the one-hundred-year floodplain elevation, provided that retaining walls shall not interfere with the flow of floodways and shall not cause increased flooding of adjacent properties.
Fence height in addition to retaining wall. Where a fence is located on top of a retaining wall, the height of the retaining wall shall be included in the height of the fence when determining compliance with the fence height limitations in the Fence Ordinance.
Existing retaining walls. This chapter shall not prohibit the maintenance of existing retaining walls that do not meet the requirements of this chapter, but were constructed prior to the effective date of this chapter.
An individual who desires a waiver or modification to the standards of this chapter may petition the Township Zoning Board of Appeals for a hearing on such request. Such request shall be processed and hearing noticed following the procedures of Chapter 285, Zoning, Article 23. In reviewing the request, the Zoning Board of Appeals shall consider the following:
Practical difficulties. Compliance with the strict letter of the regulations would create practical difficulties and unreasonably prevent the establishment of a finished grade or drainage necessary to develop the property for a permitted use.
Extraordinary circumstances. There are exceptional or extraordinary circumstances or physical conditions applicable to the property involved, such as natural features, unusual grades on the property, or adjacent property or drainage problems that do not apply generally to other properties in the Township. The conditions resulting in a request cannot be self-created.
Public safety and welfare. The granting of a waiver or modification will not create a hazardous condition, increase the risk of erosion or create drainage or flooding problems on adjacent or other nearby properties.
Drainage. Granting a waiver shall not have an adverse impact on the drainage of the site and adjacent lots and shall not disrupt natural drainage patterns or flow of floodwaters. The granting of a waiver or modification will not be contrary to the Township Floodplain Ordinance.
Natural features. The granting of a waiver or modification will minimize impact on natural features. The Zoning Board of Appeals may specifically grant modifications to this chapter for retaining walls utilized to minimize disturbance to woodlands or wetlands.
Neighborhood character. The granting of a waiver or modification will not impact views from adjacent properties or alter the essential character of the neighborhood.
Building and engineering standards. The granting of a waiver or modification will not be contrary to the Building Code or accepted building and engineering standards.