Citizen's Guide to the Subdivision Process

The purpose of the Subdivision Ordinance is to control the division of land within the unincorporated areas of St. Louis County. St. Louis County has had subdivision regulations since 1927. Legal parcels of land (usually found on plats recorded in the Recorder of Deeds office), can be subdivided.

Plats are to be submitted to the St. Louis County Department of Planning, (314-615-5186), Fifth Floor, of the Administration Building, County Government Center, 41 South Central Avenue, Clayton, Missouri, 63105. For street right-of-way and related storm drainage construction requirements, the developer/owner should contact the Department of Highways and Traffic (314-615-8563), and for sanitary and storm sewer construction requirements the developer/owner should contact Metropolitan St. Louis Sewer District (MSD) (314-768-6272).

Where do I start if I want to subdivide?

Sketch Plan

The first step a lot owner can take when contemplating the subdivision of land is to submit a Sketch Plan. The developer/owner should submit four (4) copies of a sketch plan to the Department of Planning. Sketch Plans don't require a surveyor/engineers seal, and no fees are required. Submit a Sketch Plan if you are unfamiliar with the subdivision process, because it is an inexpensive way to obtain valuable feedback about your lot.

Preliminary Plat

The developer/owner may skip the Sketch plan and submit five (5) copies of the Preliminary Plat to the Department of Planning together with the Review Fees and approval of the subdivision name from the Recorder of Deeds (314-615-7184). An approved Site Development Plan, (SDP), suffices as a Preliminary Plat. The developer/owner may want to review the  Preliminary Plat Information Sheet prior to submission of a plat to expedite the approval process. The Department of Planning coordinates and distributes comments and/or copies of approved Preliminary Plat to the developer's representative, County Departments, and appropriate Agencies involved.

Display Plat

After the Preliminary Plat/SDP is approved, the developer/owner may submit two (2) copies of the Display/Unit Plat to the Department of planning together with the appropriate Review Fees. The Display House Plat is reviewed by the Department of Planning for compliance with the approved Preliminary Plat/SDP, see  Display Plat Information Sheet for more information. If approved, the developer/owner submits the original for the Director of Planning's signature, and then it is release for recording by the developer/owner.

Improvement Plans

All required improvements such as; grading, roads, sewers, retaining wall etc, are shown on the Preliminary Plat/SDP. Prior to recording a Record Plat and construction of these improvements, the developer/owner must submit two (2) copies of Improvement Plans to the Departments of Highways, reference the "Design Criteria for the Preparation of Improvement Plans" manual for additional plan submittal criteria. The Metropolitan St. Louis Sewer District (MSD) reviewed the plan (provided by the Department of Planning) for detention requirements, adequacy of downstream storm sewer system or natural discharge point, provision of on-site storm and sanitary sewers and the adequacy of the downstream sanitary sewer system. After all review comments have been addressed, the developer/owner submits nine (9) copies of Improvement Plans to the Department of Highways and Traffic for final approval and distribution. The Metropolitan St. Louis Sewer District collects sewer escrows at this stage of the process.

Deposit/Escrow Procedures Required for Improvements

St. Louis County requires developer/owners to provide a guarantee for the installation of subdivision improvements (1005.080). Before a subdivision plat can be approved, the developer/owner is required to guarantee the completion of proposed improvements and create a maintenance account for new public streets, related storm sewers, and other improvements as required. This is achieved by execution of a deposit agreement for up to three (3) years to allow the developer/owner to complete public improvements. The developer/owner may choose to use cash or an irrevocable letter of credit.

The Department of Planning uses Current Unit Costs to determine required subdivision improvements, based on plans approved by the Department of Highways and Traffic. The Metropolitan St. Louis Sewer District (MSD) administers a separate process to guarantee the installation of sanitary sewers and those storm sewers not in the public right of way. However, the Department of Planning requires written confirmation from MSD that the developer/owner has complied with MSD's guidelines. Developer/owner may submit an American UE contract and layout plan that complies with the St. Louis County Subdivision Ordinance instead of providing a deposit for streetlights. Provisions for water mains are also included in the County's estimate, based on submitted bids confirmed by the Missouri American Water Company or a licensed plumbing contractor. For more information see the Deposit Agreement Submission Procedures and the Inspection and Release Procedures.

Record Plat

The final stage in the subdivision process is the Record Plat, and the developer/owner should submit six (6) copies of a proposed Record Plat and required fees. Please consult the Record Plat Information Sheet for additional requirements. If improvements are not installed prior to submission of the Record Plat, then a Deposit Agreement, backed by cash or Letter of Credit, covering the cost of installing improvements shown on the Improvement Plans is required. Trust Indentures are required when a subdivision contains common elements. The trust indentures are submitted by an attorney and reviewed by the County Counselor's Office. The Department submits the Record Plat, Deposit Agreement, and Trust Indentures to the County Council for review and approval. After the County Council approval, the developer/owner must submit an original copy of the Record Plat for signature by the Director of Planning, and then it is released for recording by the developer/owner.

Lot Split Plat

In addition to the normal subdivision process, a single lot can be divided into two lots using the Lot Split Procedure. This procedure can only be used when there are no variances or required improvements. Normally, the Lot Split Procedures is used in commercial subdivisions because they have fewer requirements. The developer/owner must submit six (6) copies of the plat and required fees to the Department of Planning. The Lot Split Plat will be reviewed by Department of Planning for compliance with the Zoning and Subdivision Ordinances. After the Department of Planning approval, the original Lot Split Plat is signed by the Director of Planning and released for recording.

Other - Boundary Adjustment and Condominium Platting

In addition, the Subdivision Ordinance also regulates the movement of existing property lines and the consolidation of lots via the  Boundary Adjustment Plat review process, also see the Boundary Adjustment Information Sheet. Also, the Department of Planning reviews Condominium Plats. There are no ordinance sections addressing Condominium requirements, but the Condo Information Sheet provides insight into the plat submission requirements. The Developer/owner should submit two copies of the Boundary or Condominium Plat and required fees to the Department of Planning for review.



Department of Planning
St. Louis County Government
41 S. Central Avenue, 5th Floor
Clayton, Missouri 63105

Phone   314-615-2520
Fax 314-615-3729   
[email protected]