The Engineering Department is responsible for the review and approval of commercial and residential plans, regulating development in the 100-year floodplain, issuing utility excavation permits and the review of all Planning & Zoning Commission submittals. Other projects managed by the Engineering Department include: traffic control, signals, traffic related items and working with residents, developers, and engineers on wastewater, storm water, and drinking water issues.
Find out more about the I-70 Improvement Project through O'Fallon.
ENGINEERING » As-Built Permit
ENGINEERING » Boundary Adjustment Application
ENGINEERING » Capital Improvement Projects
ENGINEERING » Driveway Installation Application
ENGINEERING » Easement Dedication Plat/Vacation
ENGINEERING » Excavation Permit
ENGINEERING » Floodplain Development Permit
ENGINEERING » Grading Permit
ENGINEERING » Over-sized Load
ENGINEERING » Record Plat Application
ENGINEERING » Residential Site Construction Plan Application
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Downloadable Construction Plans
- Residential/Commercial Standard details (PDF)
- Grading Plan Standard details (PDF)
- Residential/Commercial/Grading CAD files (contains the above details in CAD format)
Concrete Pavement and the Eastern Missouri Pavement Consortium (EMPC)
All concrete placed within the City of O'Fallon must be submitted to and approved by the Eastern Missouri Pavement Consortium (EMPC). Approved mix designs will be stored on their website for use. Specifications for concrete pavement are also provided. Please reference the EMPC brochure (PDF) for additional information. Any new mix design that is submitted may take serveral weeks before approval is issued.
The website to access the EMPC is empcpavement.org. In order to view information on the website, a free account is required. An account can be created by clicking "Login" on the homepage.
Excavation Permits (Who is digging near my yard?)
Utility companies are constantly digging in new utility lines around the area. New lines for high-speed internet, telephone, fiber optics, cell phones, plus new gas lines and adjustments to water and electric lines cause contractors to open up the ground, install pits and boxes, and then install their utility. These are usually shorter projects and remain mostly in the grass areas. For an interactive map showing the active excavation permits in your area, please click here.
For questions regarding one of these permits, please call 636-379-5596.
Recently Adopted Ordinances
The City uses a third party company to publish updates to the City Code. These updates are only updated a few times per year. The ordinances below were approved recently, and will affect projects that require the Engineering department. Please refer to these updated ordinances. Once they are updated on the City Code, then they will be removed from this list. The full text of these ordinances is available here.
- Chapter 405 revisions – Effective for new developments beginning with November 1,2018, Planning & Zoning recommendations (Ordinance 6496; approved September 13, 2018). (PDF)
- Chapter 406 revisions – Effective immediately for all new and existing permits (Ordinance 6506; approved October 11, 2018). (PDF)
- New FEMA floodplain maps may affect some residents (January 2016)
- See if a property is located in a floodplain
- Floodplain insurance
- Floodplain Development Permit Application (PDF)
- Professional Certification for LOMR Application (PDF)
- Why is my Flood Insurance Costing More? (The Biggert-Waters Flood Insurance Reform Act of 2012) and Elevation Certificates – Who Needs Them and Why
Learn how to apply for a permit when replacing, modifying or widening your driveway, including the process and standards set forth. Go to the Driveway Permits webpage.
This division's purpose is to review and conduct residential and commercial construction inspections of storm sewers, sanitary sewers, water mains, streets, grading, and other site development items assuring for code and approved construction plan compliance and quality of construction.
Interactive GIS Map
Some layers of the mapping system are featured in order to help provide some basic information to the public. Please note that the locations of the objects within this mapping system should be used for reference only. Field verification of the data may be needed. As well, some data may not be published for security reasons.
Contact Engineering staff