Jefferson County, MO Environmental Rules: Stormwater Management (2026)
Key Facts
- Permit trigger
- 5,000 square feet of land disturbance
- Mandatory BMP threshold
- 1 acre or more disturbed
- Smallest tier permit fee
- $250.00 (rising to $300.00 in 2026)
- Minimum violation fine
- $200.00 per day
- Administering department
- Department of Public Works
- Governing chapter
- Code of Ordinances Chapter 505
Summary
Unincorporated Jefferson County requires a land disturbance permit for any project disturbing 5,000 square feet or more, with structural stormwater Best Management Practices mandatory at one acre. The Department of Public Works administers permits under Chapter 505, with violations charged as misdemeanors carrying at least a $200.00 fine per day.
Permit Required. No person may engage in any land disturbance activity, including persons engaged in land disturbance activity related to utility installation or maintenance, without first obtaining a land disturbance permit from the County, except as provided in this Chapter. All new or redevelopment projects disturbing five thousand (5,000) square feet or greater are required to obtain a land disturbance permit. Land disturbance activities that disturb five thousand (5,000) square feet to less than one (1) acre are generally not required to implement permanent water quality Best Management Practices (BMPs) unless the Director of Public Works determines that a permanent BMP such as a swale, ditch, check dam or other similar measure is necessary, or unless they are part of common plan of development or sale.
Full Breakdown
010. 190(A) bars land disturbance, including utility installation or maintenance work, without a permit from the County once a project crosses 5,000 square feet. Between 5,000 square feet and one acre, permanent water-quality BMPs are not automatically required unless the Director of Public Works orders a swale, ditch, check dam or similar measure, or the work is part of a common plan of development or sale; at one acre or more, structural or non-structural BMPs addressing long-term runoff quality become mandatory. 010(A)(2). 00/acre above 25 acres).
190(C) cover disturbances under 5,000 square feet outside a common plan of sale, ordinary crop farming and tilling, permitted quarry operations, and emergency work necessary to protect life or property. 050(A) to County inspection of the site and constructed BMPs for the life of the BMP.
Violations & Fines
Section 505.050(C) makes any Chapter 505 violation a misdemeanor with a minimum fine of $200.00, with each day of a continuing violation a separate offense subject to Revised Statutes of Missouri limits. The Director of Public Works or a designee can issue a summons to Jefferson County Municipal Court under Section 505.050(D)-(E), and the County may also seek injunctive relief or use the permittee's performance guarantee to complete or restore erosion control work under Section 505.050(B) and (F).
Frequently Asked Questions
When does a Jefferson County project need a land disturbance permit?
Does my one-acre development need stormwater controls beyond a permit?
What does a Jefferson County land disturbance permit cost?
What happens if I disturb land in Jefferson County without a permit?
Sources & Official References
Other rules in Jefferson County
Compare Jefferson County to another location·View the Missouri environmental rules overview
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