Retaining  walls are designed to level out sloped ground. They hold back  the soil  to prevent it from moving to lower ground. Retaining walls hold  back  tons of weight. They also have to withstand inclement weather   conditions and even seismic activity. If they are not properly designed   and constructed, they can pose a danger and may quickly fail.
Why a Structural Engineer is Needed for Retaining Wall Designs
With a properly designed retaining wall,  you can maximize your property  use and increase its value. A trained  structural engineer can help you  with the best retaining wall for your  situation. The engineer may  consider the lay of the land and the  drainage when discussing the wall  location and design.
The design of the retaining wall will  consider many factors including  soil properties, and the elevation and  slope of the ground. The height  and breadth of the wall holding the  soil in place is another crucial  consideration.
Permit Requirements
You  generally need a permit if you plan to make changes and additions to   your property. The retaining wall may require such a permit. Your local   jurisdiction can help you with information on what is needed in your   area.
In general, you’ll probably  need a permit signed off by the local  authority if your planned wall is  more than four feet high. If the slope  above the wall is 2:1, in the  state of California, for instance,  sign-off by an engineer is not  optional. There may also be permit  requirements related to the support  of surcharges amongst other things.
If  you plan to excavate or move the soil, an engineer will have to  create  a grading plan that shows how you’ve taken care of the drainage.   Cities have different building codes and regulations. A structural   engineer will make sure that you don’t fall foul of the law.
A Structural Engineer Will Design Retaining Walls to Last a Lifetime
Regardless of whether you need a permit or not, a structural engineer  will ensure that you have a wall that is designed and built to last a  lifetime. The engineer will make the following evaluations:
Best location – the engineer will take a holistic view of your property  and ensure that the wall is optimally designed. He or she will consider  the drainage, the amount of soil excavation, and the best placement for  enhancing the property’s curb appeal
Design the wall height and shape – the engineer will design a retaining  wall in a shape that contours the land and at the appropriate height.  They will identify the slopes on either side of the wall and take into  account extra weight loads caused by roads, patios, and pools, etc. They  will also design the required retaining wall setback.
The design of your retaining wall may take account of water table  conditions and concentrated top loads. Engineers have been trained to  understand the lay of the land and the way that soil and water pressures  can combine to create stresses on the wall. They have tables and  formulas on which they base their designs. They also know how to take  care of the drainage on the new landscapes.
Get the Best Out of Your Retaining Wall
Well-designed retaining walls will last for decades, requiring little or  no maintenance. They free up space for lifestyle areas like patios and  garden areas. Still, unless they are appropriately designed, they can  produce drainage problems or in the worst cases, they may collapse.
Your retaining wall will face many stressors over the years. This is why  a structural engineer is highly recommended for retaining walls.