A permit and engineer design is required for any retaining wall in Peachtree City over 4 feet in height as measured from the top of the footing.
1. Please fill out and sign an application for a building permit. (Right side menu bar)
2. Submit 2 separate copies of standard site plans showing the following:
- Show distances to property lines
- Show distances to any existing structures
- Show perimeter control measures (silt fence)
- Show water run-off (use arrow to indicate flow of water)
- Show height of the wall by the top of the wall elevation (T.W.) and bottom of the wall elevation (B.W.)
- Show which side of the wall is retaining soil
- Show location of all easements
- Show setback lines
- Show the location of utility lines (sanitary sewer, water, under ground electric and communication cables)
- Note: Wing walls constructed as part of building foundation shall not be higher than 10 feet
- Note: If a retaining wall is greater than or equal to 30 inches it may not be allowed in certain building setbacks and will require a safety restraint system at the top. (See City Planner or Building Official)
3. Submit 2 separate sets of detailed retaining wall construction plans drawn to scale containing the following information:
- Provide an introductory discussion about the project and retaining wall(s). Include discussion about the loads used in the designs and impact/vibration consideration. Mention any loads imparted by other structures and how they affect the design.
- Provide a site plan showing the subject walls with them numbered and with station numbers for each wall. Provide profiles for all walls showing station numbers, elevations (existing and proposed), and any locations where utilities penetrate or go under a wall, etc. Plans must be sealed by a Professional Engineer registered in Georgia.
- Provide a set of design calculations for each wall. The calculations should include soil parameters (for footing/leveling pad, backfill behind the walls or any other use), safety factors (names, required value, and calculated value), slope conditions both sides of the walls, design loads, etc. Calculations must be sealed by a Professional Engineer registered in Georgia. Include Global Stability Analyses if applicable. If not applicable, state so in the introductory discussion.
- Provide typical sections. Show wall batter, drainage aggregate or geotextile behind the wall, swale behind the wall for stormwater drainage, footing or leveling pad, stabilization details downstream of a storm pipe penetration where the effluent is released at the wall, etc.
- Provide details/specifications for the wall blocks, features which retain the wall blocks in place (pins, lips, etc.), geogrid, a system to ensure proper tensioning of the geogrid, grout for sealing wall penetration areas, etc.
- State construction sequences for unusual/unique situations such as where geo-grid extends under a structure or must go around a storm pipe and/or its related structure.
- Clearly identify on the plans the limits for safety restraint systems atop or immediately behind walls. Restraint systems are required at wall heights exceeding 30 inches. Minimum height for human restraint system is 42 inches with openings complying with the requirements that a 4 inches sphere cannot pass between members. Guardrail for vehicular restraint should be clearly shown on the plans and detail for the guardrail shown.
- Provide a copy of a letter to the owners from the wall design engineer instructing them as to proper repair procedures for damage to a wall face or geogrid area.
- Provide an executed Engineer's Certificate for the wall or walls signed by the Engineer who seals the plans & design calculations for the design and then, upon completion, for the construction.
- Maximum allowable height for modular retaining walls in the City of Peachtree City shall be reviewed and approved by the city. No geogrids will be acceptable within any right-of-way limit nor within any drainage or sanitary sewer easement.
- Provide a narrative and design for any groundwater anticipated behind the retaining wall. Water on the front side of the wall will require special engineering design.
- If trees fall within 10 feet of the retaining wall foundation then special steps must be shown by the design engineer to ensure that the trees will not impact the foundation.
- Special design will be required if the existence of irrigation, storm drains or water lines are within the reinforced zone behind the retaining wall.
- Under no circumstance will trees be allowed in the reinforced zone behind the retaining wall.
- Submit 2 copies of structural analysis for each retaining wall. All plans and structural analysis must be sealed and signed by a registered Professional Engineer licensed in the state of Georgia.
4. All retaining walls (to include modular) are to be built under the supervision of a Professional Engineer registered in Georgia (preferably the engineer that sealed the design plans and calculations) who will certify to Peachtree City Building and Engineering Departments that the walls were built per approved plans.
The preceding requirements apply to most simple retaining wall projects; however, Peachtree City may determine that unusual circumstances dictate the need for additional information.