RPAs are regulated waterbodies and associated corridors of environmentally sensitive land that lie alongside or near the shorelines of streams, rivers and other waterways which drain into the Potomac River and eventually into the Chesapeake Bay. In their natural condition, RPAs protect water quality, filter pollutants from stormwater runoff, reduce the volume of stormwater runoff, prevent erosion, and perform other important biological and ecological functions. In Fairfax County, RPAs include any land characterized by one or more of the following features:
- Tidal wetland;
- Tidal shore;
- Water body with perennial flow;
- Nontidal wetland connected by surface flow and contiguous to a tidal wetland or water body with perennial flow;
- Buffer area that includes any land within a major floodplain and any land within 100 feet of a feature listed in 1-4.
Development, uses and activities within RPAs must comply with the County’s Chesapeake Bay Preservation Ordinance (CBPO), Chapter 118 of the Code of the County of Fairfax to protect and restore the quality of state waters.
The county has prepared guidance maps showing estimated locations of the RPAs.
- The Interactive RPA Map is the simplest way to view the Watershed and RPA boundaries by entering the property address.
- JADE is a more comprehensive mapping application with over 170 layers to view, combine and analyze. The RPA boundary is one of the available layers in the online GIS system. Further instructions are available.
The above mapping tools depict the general presence and location of regulated areas. However, the determination of the exact width and location of the RPA boundary may be required by a site-specific study before the county can grant approval to start land-disturbing activities on properties in or near RPAs. For more information, see the Letter to Industry dated July 3, 2008 or the “When are site-specific RPA delineations required and Why?” FAQ.
Any development, land disturbing activity or other use within an RPA generally requires prior approval from the county. The specific type of application and procedure for obtaining the approval depends on the nature and extent of the encroachment. For information regarding a specific project and associated application requirements, please contact a stormwater specialist at 703-324-1720, TTY 711.
Existing structures and uses in the RPA including lawns, gardens and other maintained landscaping, may remain and be maintained as they existed when the RPA was designated on the property (e.g., July 1, 1993 or November 18, 2003) but may not be expanded upon unless a waiver or exception is granted.
Subject to county approval, and to maintain the functional value of the buffer area, vegetation may be removed from the 100-foot buffer for the following reasons:
- To provide reasonable sight lines, general wood lot management and habitat management. Any vegetation removed must be replaced with vegetation that provides equivalent water quality benefits and environmental protection. Form to request approval.
- To create access paths. Such paths and appurtenances cannot cause erosion. Form to request approval.
- To remove dead, dying or diseased trees and shrubs, and to remove noxious weeds or invasive exotic plants. Any vegetation removed requires replacement vegetation equally effective in providing water quality benefits and environmental protection. Form to request approval.
- To provide for shoreline erosion control. Buffer must be reestablished with native, woody vegetation. Form to request approval.
- Development is not permitted when there is sufficient buildable area outside the 100-foot buffer or if the property was subdivided after the Chesapeake Bay Preservation Ordinance (CBPO) or a subsequent amendment was adopted (e.g., July 1, 1993 or November 18, 2003). For more information, see the “What are the loss of buildable area provisions?” FAQ.
- Accessory structures like sheds, gazebos, pools, or detached garages may not be located within the 100-foot buffer without the approval of an exception via a public hearing with associated fees. Form to begin the process.
- Clear-cutting of vegetation is not permitted nor is the removal of native vegetation to create lawns.
- Application of pesticide and fertilizer is strongly discouraged.
The construction of sheds in the RPA may be allowed but are subject to an exception process requiring a public hearing [form to begin the process] and associated fees. Sheds should only be located within an RPA when there is no reasonable alternative for locating the shed outside of the RPA boundary. For more information, see the “What are the requirements for the construction of accessory structures?” FAQ.
Fences are allowed in the RPA without an exception or waiver and subject to the following design requirements which collectively maintain the functional value of the buffer:
- Fences should be designed so that they do not inhibit or alter surface flow (i.e., water must be able to flow under and through the fence unimpeded).
- Vegetation may only be removed to provide for the actual placement of the fence.
- Where vegetation is removed, it must be replaced with other native vegetation that is equally effective in retarding runoff, preventing erosion and filtering stormwater runoff.
- Fences should be located to avoid the removal of trees.
If the fence is to be placed in an area that is an existing (pre-RPA establishment) maintained lawn, the revegetation requirement would not be applicable.
Decks are treated as minor additions under the Chesapeake Bay Preservation Ordinance (CBPO) and therefore allowed, subject to approval of an administrative waiver. The administrative waiver process is available only for minor additions to homes constructed prior to the effective date of the RPA map amendment (e.g., July 1, 1993 or November 18, 2003). An administrative waiver can be requested using the Minor Addition Exception Request Form and Water Quality Impact Assessment, during the building permit review process for construction of the deck. For more information, see the “What are the requirements for the construction of minor residential additions?” FAQ.
Yes. Non-compliance with the RPA restrictions is a violation of the Chesapeake Bay Preservation Ordinance (CBPO) and can result in penalties. At a minimum, violators will be required to restore the RPA in accordance with the CBPO and Fairfax County’s Public Facilities Manual (PFM). An appropriate restoration plan must be developed and submitted to the Department of Land Development Services for review and approval. The objective of the plan is to restore the RPA’s primary functions so it can effectively remove pollutants from stormwater runoff, which is achieved via the planting of trees, shrubs and ground cover. Planting densities are prescribed by CBPO §118-3-3(f) and the PFM.
In addition to preparing a restoration plan, any person who violates any provision of the CBPO may be subject to civil penalties up to $5,000 per day of violation.
Generally, if a commercial or residential property (i.e., lot) existed prior to the effective date of the Chesapeake Bay Preservation Ordinance (CBPO) amendments, November 18, 2003, and consequently the buildable area of the lot was so impacted by the delineation of an RPA to a degree that the property could not be reasonably developed then it may qualify for the provisions of the loss of buildable area under the CBPO. Specifically, the loss of buildable area provision allows for construction of 5,000 square feet of impervious (i.e., a surface comprised of material that significantly impedes or prevents natural infiltration of water into the soil) area in the RPA exclusive of the driveway, and 10,000 square feet of disturbed area in the RPA exclusive of the driveway and septic field. An administrative waiver [form to request approval] is available for the construction of new homes on lots platted prior to the effective date of the Chesapeake Bay Preservation Ordinance (CBPO) amendments, November 18, 2003.
For a project to qualify for an administrative approval the allowed encroachment must be the minimum necessary to afford relief and may only extend 50 feet into the RPA. Mitigation of the encroachment will be required. The construction of new homes in the RPA not meeting the above requirements may still be possible but would be subject to an exception process requiring a public hearing [form to begin the process]. For more information, please contact a stormwater specialist at 703-324-1720, TTY 711.
A minor addition is an addition that has a footprint of 1,000 square feet or less or does not comprise more than 2 percent of the lot area up to a maximum of 2,500 square feet, whichever amount is greater. The eligibility for such encroachments depends on when the home was built. In determining eligibility, the date of construction of the home is the date that the Residential Use Permit (RUP), “Occupancy Permit”, for the home was issued.
- To add a minor addition that encroaches into a 1993 RPA mapping designation, the home must have been constructed prior to July 1, 1993 (effective date of the Chesapeake Bay Preservation Ordinance).
- To add a minor addition that encroaches into a 2003 RPA mapping designation, the home must have been constructed prior to November 18, 2003 (effective date of the 2003 amendments).
For an allowed, residential minor addition exception, the total new impervious (i.e., a surface comprised of material that significantly impedes or prevents natural infiltration of water into the soil) area that may be added to the lot is cumulative. For example, if you obtain a minor addition exception for 800 square feet of impervious area and decide to apply for another minor addition exception a year later, you would have only 200 square feet of impervious area allowed under the minor addition exception, not an additional 1,000 square feet. The cumulative limit on the maximum additional impervious area shall continue indefinitely, regardless of ownership of the property.
If the associated land disturbance is less than 2,500 square feet, use the Minor Addition Exception Request Form [form to request the exception]. If the total proposed disturbance exceeds 2,500 square feet and requires a grading plan, use the RPA Exemption/Exception Request Form [form to request the exception].
Note: Detached structures are not considered minor additions but considered accessory structures. The county’s ordinance for accessory structures is based on the state regulations which do not allow detached structures to be treated as minor additions. For more information on detached structures, see the “What are the requirements for the construction of accessory structures?” FAQ.
Accessory structures within the RPA are subject to the findings listed in county code §118-6-6 and the criteria in §118-6-8. The construction of accessory structures, such as detached garages, patios and sheds, in the RPA may be possible but are subject to an exception process and require a public hearing [form to begin the process here] with associated fees. For more information, please contact a stormwater specialist at 703-324-1720, TTY 711.
A Water Quality Impact Assessment (WQIA) is an analysis of the impacts on water quality when a project is proposed within an RPA. The purpose of the WQIA is to ensure protection of RPAs consistent with the goals, objectives and requirements of the Chesapeake Bay Preservation Ordinance (CBPO) to:
- Identify the impacts of the proposed project on water quality.
- Ensure that the proposed land disturbance will occur in a manner that will be least disruptive to the natural function of RPAs.
- Propose mitigation that will address water quality protection through preserving or restoring all buffer functions including stormwater pollutant removal, erosion and sediment and runoff control.
WQIA’s are required for any land disturbance, development or redevelopment within an RPA unless exempt under Article 5 or unless waived by the Director of Land Development Services in accordance with the provisions of county code §118-6-5.
Boat docking structures and seawalls (bulkheads) are water dependent structures, and are allowed in the RPA, per the Chesapeake Bay Preservation Ordinance (CBPO) §118-2-1, but only with a county-approved Water Quality Impact Assessment. Before any construction on the shoreline or water’s edge begins, permits and approvals from the respective federal, state or local agencies will likely be required. The number and type of necessary permits and approvals will vary depending on the type, size and location of the project. For more information, see the Fairfax County Tidal Shoreline web page.
Site-specific delineations of RPAs are much more accurate than the county’s illustrative mapping.
The first county RPA guidance maps were adopted in 1993 and were prepared using existing map information to estimate the RPA features specified in the Chesapeake Bay Preservation Ordinance (CBPO) §118-1-7(b). The maps were updated in 2003 based on a 2-year field study to determine the limits of all perennial streams in the county. There have since been separate amendments revising RPA guidance maps for smaller areas of the county. The maps provide landowners with a tool showing the general presence and location of regulated areas.
Given that the county RPA guidance maps are not based on site-specific, field-verified features, RPA boundary delineation studies are required for all site-related plans on which RPAs are shown on the adopted county map (e.g., infill lot grading plans, subdivision plans, rough grading plans, site plans). Additionally, for infill lot grading plans, the submitting engineer must certify on the plan that all the features that comprise the RPA have been reviewed and that the RPA boundary depicted on the plan is accurate. It is the applicant’s responsibility to show the appropriate RPA boundaries, applying the criteria in §118-1-7 of the CBPO, on all plans of development submitted for review.
The Public Facilities Manual (PFM) and CBPO set forth the criteria for conducting and submitting site-specific boundary delineation studies. Site-specific studies to determine the exact width of the RPA may be required before approval to start land-disturbing activities on properties in or near RPAs. Please note that the adopted RPA map or the RPA layer (such as in JADE) is not revised when a site-specific RPA Delineation Plan is approved. Approved site-specific RPA Re-delineation Plans may be obtained through Fairfax County’s Site Plan Viewer, or requested from Fairfax County Land Development Services, Records and Information Management Branch, 5th floor of the Herrity building, 12055 Government Center Parkway, Fairfax, and via email at LDSRecords@fairfaxcounty.gov.
For building permit applications, where a grading plan is not required (i.e., total disturbance is less than 2,500 square feet), the RPA boundary shown on the associated house location plat may be based on the adopted county map and not require a site-specific delineation.
For more information, see Letter to Industry dated July 3, 2008.