Department Resources

RPA & Floodplain Review for Minor Additions

Minor residential additions can be reviewed and approved for construction in a Resource Protection Area (RPA) per County Code 118-5-5 (A) and 118-5-5 (B), provided the following conditions are met:

The primary dwelling (house) was built prior to the establishment of the RPA (before Jul. 1, 1993, or Nov. 18, 2003, depending on the RPA mapping designation). In determining eligibility, the date of construction of the home is the date that the occupancy certificate or Residential Use Permit (RUP) was issued.
The proposed addition is attached to the primary dwelling (house). Patios and detached structures such as detached garages, gazebos and swimming pools do not qualify as an addition.
The footprint of the proposed addition is no larger than 1,000 square feet, or 2% of the total lot area up to a maximum of 2,500 square feet, whichever is greater. These are cumulative totals for the new impervious area that may be added to the lot under all exception requests. Note: Uncovered deck projects do not count towards the impervious total as they are considered pervious improvements, i.e., penetrable by water.
The associated land disturbance for the project is less than 2,500 square feet.
If the proposed addition is located within 15 feet of a floodplain boundary (or for decks, within the floodplain boundary), a separate Floodplain Use Determination (FPUD) is required. The FPUD must be approved before the RPA minor addition waiver can be approved. See the FPUD permit library guide for further submission details.
A building permit cannot be issued for the proposed addition until the RPA Waiver, and if applicable, the FPUD, is approved.

NOTE: If the total proposed land disturbance exceeds 2,500 square feet and requires a grading plan, a separate process/form is required. For more information, contact the Site Development and Inspections Division.

FPUD Submissions Process

RPA Submission Process

Obtain a scaled House Location Plat with the proposed addition project shown to scale. For more information on how to obtain and scale a plat, please visit zoning’s Submitting House Location Plats page.
Apply for your RPA waiver online in PLUS under the Site tab. If you are a first-time user, you must first register for an account.
1. Click on the “Site” Module Tab
2. Click “Create an Application”
3. Check the “I have read and accepted the above terms”
4. Click “Continue Application”
5. Click “Waivers”
6. Click “Continue Application”

Process Application — Click for full-size image.

Fill out the “Location and People” Tab
1. Enter the Parcel ID Number (Tax Map number from iCare). Do not include spaces, parenthesis nor hyphens. If the number does not work as listed, try entering the majority of the number and “searching” for the full, valid parcel ID.

1. Continue the Application as prompted.

Note: A licensed professional is not required to prepare WAIV applications. Individual homeowners may prepare and submit their own application.

Fill out the “Application Detail” Tab
1. Project Name: Project type (e.g., uncovered deck or sunroom)
2. Project Description: Project description, to include size of the proposed addition, and “in the RPA”
3. Waiver Type: RPA Minor Additions (Walk Through WRPA)
4. Waiver of: County Code
5. Code Reference: Select either 118-5-5(A) or 118-5-5(B), depending on the year the house was built
6. Code Reference for Parent Plan: no parent plan (land disturbance is less than 2,500 sq.ft.)
7. Waiver Category: Exception

Step 2: Application Detail>Application Info Cont. requires you answer a series of questions based on the scope of your project. Subsequent questions appear depending on how you answer the initial questions about whether the project is a deck, and whether it is covered or uncovered.

Review the “Application Information” on the “Review” Tab
Click “Continue Application” on the “Associated Forms” Tab as there are no additional forms required for this application type.
“Receipt/Record Submittal” Tab (your WAIV Record Number has been created for tracking ex. WAIV-2024-00047). Note, there is no submission fee for this record type.

Upload the scaled House Location Plat and click “Upload and Validate.” Then click “Continue.”

Validate and Version your Plans (i.e., PDF of your plat) and once validated, click “Continue.“

Add a sheet number and title at the second Upload step “Sheets.” Click “Continue.“

Click “Finish” to successfully submit the WAIV record for county review.

You will receive a confirmation email of your review package being submitted for processing.

The average review cycle for RPA WAIV minor addition exception requests is five business days.

Land Development Services

Land Development Services Alert:

Department Resources

RPA & Floodplain Review for Minor Additions

RPA Submission Process

More Information on RPAs

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