Acreage, privacy and natural beauty along the Potomac — estate lots in Fairfax County where Georgetown Pike is a protected state byway, most homes sit outside the public sewer service area on their own septic systems, and many draw their water from private wells.
Great Falls is a semi-rural Fairfax County community of estate homes on one-acre-and-larger lots, framed by the Potomac River, Great Falls Park and miles of wooded trails. It is unincorporated, with no town government of its own. The Census Bureau counts it as the Great Falls CDP, which recorded 15,953 residents in the 2020 census. The CDP covers about 25.4 square miles of land and sits under a single ZIP code, 22066. The Potomac forms its northern and eastern edge, and Difficult Run and Leesburg Pike form the southern one. Two things shape a purchase here more than anything a listing sheet shows. There is no Metrorail station, so every trip starts in a car. And most of Great Falls is not on public sewer: homes are served by onsite septic systems, many draw water from private wells, and those systems quietly govern how many bedrooms a house may have, how much it can be enlarged, and how the deal gets financed. Both of those were still the case as of August 2026, and the county rules, figures and project statuses on this page were verified in August 2026.
Because Great Falls is unincorporated, every permit is a Fairfax County permit, and the county office that matters most here is the Health Department’s Onsite Sewage and Water Program. Septic and private-well applications, repairs and records all move through the county’s PLUS portal: a soil scientist performs the soil evaluation and an Environmental Health Specialist reviews it on site to judge whether the ground can accept and treat wastewater. Timing is a genuine constraint, not a formality. The county allows soil evaluations for proposed shallow-placed onsite systems only during months when average rainfall meets or exceeds the long-term monthly composite average for Washington Dulles International and Reagan National, and the same rule governs when water-table monitoring wells may be read. A contract written in a dry stretch of the year can hit a calendar problem before it hits a soil problem. Once a system is in, Fairfax County Code Chapter 68.1 requires the septic tank to be pumped out at least once every five years, with the pump-out reported to the county, and the county recommends testing private well water annually for bacteriological and chemical contaminants. Alternative onsite sewage systems — the engineered systems used where a conventional drainfield will not work — carry heavier standing duties, and it is worth separating the two clocks. A qualified operator must inspect and sample the system within 180 days of the system’s approval, and inspect it again every year after that. Sampling itself is then required once every five years. Each visit is reported to the Health Department by the 15th of the month following the month in which the visit occurred. On water supply, whether a particular street has a public water main is a property-by-property question — confirm service for the specific address with Fairfax Water before assuming either way. And if a septic system fails and the county’s Division of Environmental Health deems it non-repairable, the owner is required to connect to public sewer where the property lies within 300 feet of an available sanitary sewer main.
The septic system is not just a utility; it is a cap on the house. A Great Falls septic system is permitted for a specific number of bedrooms, and that permitted count — not how the floor plan is drawn — is what governs. Part of the lot is spoken for before anyone sketches an addition, because the county requires a suitable reserve area to be held aside so the system can be repaired or replaced. That is why Fairfax County routes the residential addition and alteration permit through Health Department review whenever the property is on well or septic. The same logic reaches accessory living units. Under the county zoning rules, an ALU inside the principal dwelling is capped at 800 square feet of gross floor area or 40 percent of the principal dwelling, whichever is less, except that an entire basement or cellar may be used, up to its size as of July 1, 2021. A detached ALU is capped at 1,200 square feet, is allowed only on a lot of at least two acres, and needs a special permit from the Board of Zoning Appeals. The county also limits occupancy of an accessory living unit to two people, and requires Health Department approval before the permit is granted wherever the dwelling is served by a well or septic system. A second layer sits on top of all that. The county’s Chesapeake Bay Preservation Ordinance maps Resource Protection Areas: tidal wetlands, tidal shores, water bodies with perennial flow, connected nontidal wetlands, and a buffer that takes in any land in a major floodplain and any land within 100 feet of those features. Land-disturbing activity of more than 2,500 square feet inside an RPA generally requires an exception. Development is not permitted inside the 100-foot buffer where there is sufficient buildable area outside it. And accessory structures such as sheds, gazebos, pools and detached garages may not sit in the buffer without an exception granted at a public hearing. Financing adds a third layer on top of the county’s two. FHA’s Single Family Housing Policy Handbook 4000.1, in the version HUD had posted as of August 2026, requires a well to sit at least 50 feet from a septic tank and 100 feet from a drainfield — reducible to 75 feet from the drainfield where the local authority allows, and superseded by local distances wherever those are greater — and requires the water to meet the standards of the health authority with jurisdiction, or EPA National Primary Drinking Water standards where no local or state standard exists.
Great Falls is overwhelmingly a market of detached single-family houses on large lots — custom-built contemporary and traditional homes, classic colonials, older farmhouses and the occasional small hobby farm, almost all on an acre or more and many heavily wooded. Fairfax County’s Comprehensive Plan places the community at the semi-rural northern end of the Upper Potomac Planning District. The plan describes that district as roughly 47,500 acres, about 18 percent of the county’s land area, bounded by the Potomac on the north, Difficult Run and Towlston Road on the east, Route 50 on the south, and Loudoun County and Dulles Airport on the west — so it reaches well past Great Falls to take in Reston, Herndon and the Dulles Suburban Center. Difficult Run turns up in both descriptions because the creek runs southeast: it marks the CDP’s southern edge and the planning district’s eastern one. That plan language is the 2017 edition as amended through March 6, 2018, which is the text the county had posted as of August 2026. The Great Falls Citizens Association, the volunteer 501(c)(4) that stands in for a town council in a community with no town hall, describes its role as advocating for the historic, low-density, semi-rural character of Great Falls and its natural resources. Because the area filled in lot by lot rather than in one master-planned sweep, construction eras sit side by side, and the differences that matter are rarely the ones on a listing sheet. Touring here, a short list of questions moves the needle. Where do the drainfield and its reserve area sit on the plat? What bedroom count was the system permitted for? When was it last pumped and inspected? Is it a conventional system, or an alternative one with an operator contract attached? Does the well have a recent yield and water-quality test? Does a stream or floodplain pull part of the lot into a Resource Protection Area? Does a public water main reach the street? And does the property fall inside the Colvin Run Mill historic overlay or the Turner Farm observatory lighting district? Two houses that look identical online can be very different properties once those answers come back, and the school pyramid and attendance boundary serving an address should be confirmed rather than assumed.
Great Falls sits inside the Washington suburbs, yet its land-use rules still make room for livestock, and those rules are worth reading before anyone buys a horse property here. As of August 2026 Fairfax County allows the keeping of animals as an accessory use at one animal unit per acre on any lot of two acres or more, with horses under six months old excluded from the count. Boarding horses a resident does not own is handled under a separate standard, which the county states as a horse count rather than an animal-unit density: up to five boarded horses on lots of two to under five acres, and up to eight on lots of five acres or more. Above those counts the use becomes a riding or boarding stable and requires special exception or special permit approval. Giving riding lessons is what triggers the limited riding or boarding stable administrative permit. That permit requires at least two acres and caps lessons at two students at any one time on lots of two to under five acres and four students at any one time on lots of five acres or more, with eight students per day in either case; the applicant’s primary residence must be on the same lot; lessons and riding-ring lighting run 7 a.m. to 7 p.m.; and a conservation plan approved by the Northern Virginia Soil and Water Conservation District is required. Those animal and stable standards are the county’s as of August 2026. Larger holdings can enter the county’s Agricultural and Forestal District program, which as of August 2026 sets a 20-contiguous-acre minimum for a local district and an eight-year term, with rollback taxes for the past five years plus a penalty if land is withdrawn early. The county’s 2025 A&F District annual report, dated June 30, 2026 and covering activity from March 20, 2025 through March 19, 2026, records that 69 percent of the county’s A&F districts — counted as districts, not as acres or parcels — lie in the Dranesville and Springfield magisterial districts, and Great Falls sits in Dranesville. Two overlays bear directly on exterior work. Colvin Run Mill — the 19th-century water-powered gristmill at 10017 Colvin Run Road — and its miller’s house are protected by a county historic overlay district, one of fifteen countywide as of August 2026 in which the Architectural Review Board reviews rehabilitation, new construction and exterior alterations. And in November 2023 the Board of Supervisors adopted special outdoor-lighting standards for a half-mile perimeter around the observatory at Turner Farm, 925 Springvale Road; Fairfax County announced on January 15, 2026 that DarkSky International had designated Observatory Park at Turner Farm an Urban Night Sky Place.
Based on information from Bright MLS for July 1, 2026 through July 31, 2026; data is reliable but not guaranteed.
The park that gives the community its name is federal, not county. Great Falls Park is an 800-acre unit of the George Washington Memorial Parkway administered by the National Park Service, entered at 9200 Old Dominion Drive — an address the Park Service gives as McLean 22102, even though the falls sit at the top of the Great Falls community. There the river drops through a run of steep rock ledges and then narrows hard into Mather Gorge. The Fairfax County Park Authority bought the land out of receivership in January 1953, and it transferred to the National Park Service in 1966; its trails pass the remains of the Patowmack Canal, the skirting canal begun in 1785 and completed in 1802 to move boats around the falls. Entrance fees are charged, and the park has taken card or electronic payment only, not cash, since January 1, 2025; that was still the arrangement as of August 2026. Immediately upriver, Riverbend Park is a Fairfax County Park Authority park on the Potomac at 8700 Potomac Hills Street, which the county described in August 2026 as having over 10 miles of hiking trails, including a two-and-a-half-mile stretch of the Potomac Heritage Trail. The stretch of river both parks sit on is the Potomac Gorge, the roughly 15-mile section running from the falls down toward Georgetown. The Nature Conservancy’s published description of the Gorge, as posted in August 2026, credits it with 15 globally rare species, 100 state-rare species and 30 different plant communities, and calls it one of the nation’s highest concentrations of globally rare natural communities. For a property owner the practical consequence is twofold: a great deal of the land along the river will not be built on, and the same stream corridors that drain toward it are the ones Fairfax County maps as Resource Protection Areas on private lots.
Georgetown Pike, State Route 193, is the spine of Great Falls and a legally protected road. As a state route it runs 11.79 miles from Route 7 at Dranesville east to Route 123 in Langley. Its National Register nomination records that the road was built between 1813 and 1827 by two privately organized turnpike companies, using a layered roadbed of closely fitted stone crowned in the center for drainage, and that the Commonwealth of Virginia acquired it in 1934. It was designated Virginia’s first Scenic and Historic Byway in 1974. It was added to the Virginia Landmarks Register on June 21, 2012 and listed in the National Register of Historic Places on August 22, 2012, the nomination describing it as the last surviving of the four major 19th-century Arlington and Fairfax County turnpike roads to retain integrity of design together with historic and scenic character. That status constrains what can be done to it: Fairfax County’s Comprehensive Plan calls for maintaining the Pike within its existing right-of-way, treats major realignment or widening as damaging to the byway’s historic integrity, and directs that scenic and conservation easements be sought along it wherever practical instead. In practice that means two lanes, limited shoulders and very few sidewalks. A county pedestrian-safety project presented at a public meeting on January 30, 2025 would add a refuge island, a high-visibility crosswalk, rapid-flashing beacons, ADA curb ramps and minor sidewalk extensions at the Great Falls Library crossing alone; as of August 2026 the county’s project page showed the community-engagement phase closed and gave no construction schedule. Old Dominion Drive carries the other half of the story. It follows the roadbed of the Great Falls and Old Dominion Railroad, the electric interurban whose first scheduled car reached Great Falls Park on July 3, 1906. The line stopped running in 1934, and in 1935 Fairfax and Arlington counties took the right-of-way west of Thrifton Junction in settlement of delinquent taxes; most of it became Old Dominion Drive. Where Georgetown Pike meets Walker Road is the village center — the Great Falls Village Centre shops and green, a Safeway at 9881 Georgetown Pike, the Great Falls Library at 9830 Georgetown Pike, a Saturday farmers market at 756 Walker Road, and, at 9812 and 9818 Georgetown Pike, the 1889 Forestville School and the 1929 Great Falls Grange, both owned by the Fairfax County Park Authority and listed together on the National Register in 2004. Those village-center details were current as of August 2026.
There is no Metrorail station in Great Falls. The Silver Line runs south of the community along the Dulles corridor, and the nearest stations are Spring Hill in Tysons and Wiehle–Reston East in Reston, both reached by car. Fairfax Connector Route 924 runs the Leesburg Pike, Dranesville Road and Herndon Parkway corridors between the NVCC Loudoun campus and Franklin Farm, and does not serve the Great Falls village center; that was the routing the county published as of August 2026. Georgetown Pike meets the Capital Beltway at a diamond interchange, Exit 44. Beltway exit numbers in Virginia count down as you drive north, so the next interchange toward the American Legion Bridge is the George Washington Memorial Parkway at Exit 43. Route 7 and the Dulles Toll Road carry traffic west toward Dulles International. Two road projects have changed those drives. VDOT widened Route 7 from four lanes to six between Reston Avenue and Jarrett Valley Drive and added shared-use paths on both sides — a seven-mile, $313.9 million project the department celebrated as complete on May 22, 2024. And the 495 NEXT project extended the I-495 Express Lanes 2.5 miles north from the Dulles Toll Road to the George Washington Memorial Parkway near the American Legion Bridge. Those lanes opened in late November 2025 — VDOT announced a Saturday, November 22 opening and the operator reported the lanes carrying traffic that weekend — while bridge and finishing work continued into 2026. The rebuilt Georgetown Pike bridge over the Beltway was one of seven bridges built or rehabilitated in that project; VDOT shifted eastbound traffic onto a newly built southern portion of the bridge on April 6, 2026 and said it expected the bridge finished by late spring 2026 and the project as a whole around the middle of 2026. That was the published schedule as of August 2026, so check current conditions before counting on any particular configuration. None of this changes the underlying fact: in Great Falls, walkability is a property-level question, not a community-level one, and drive times should be tested from the specific address at the hour you would actually travel.
Browse current listings, or reach Artur directly for private and off-market opportunities.
Mostly not. Great Falls sits largely outside the public sanitary sewer service area, so homes are served by onsite septic systems, and many also draw water from private wells rather than a Fairfax Water main; that was the position as of August 2026. Whether a particular street has a water main is a property-by-property question, not a Great Falls-wide one — confirm service for the specific address with Fairfax Water before assuming either way. If a septic system fails and Fairfax County’s Division of Environmental Health deems it non-repairable, the owner is required to connect to public sewer where the property lies within 300 feet of an available sanitary sewer.
Start with the Fairfax County Health Department record for the property: the construction permit, the bedroom count the system was sized for, the system type, and where the drainfield and its required reserve area sit on the plat. Then confirm the last pump-out, and find out whether it is an alternative onsite sewage system, which carries standing operator inspection, annual visit and five-year sampling duties. On the water side, get a current well yield and a bacteriological and chemical water-quality test. One timing trap: soil evaluations for proposed shallow-placed systems are allowed only in months that clear the county’s rainfall threshold, so if a repair or replacement system may be needed, the evaluation window can be seasonal. These county requirements were current as of August 2026. Artur can pull the county record and walk it line by line with you before your contingency runs.
Sometimes, and the septic system decides. A Great Falls septic system is permitted for a specific number of bedrooms, so a house on septic cannot simply gain a bedroom because the plan has room for one, and Fairfax County routes the residential addition and alteration permit through Health Department review whenever the property is on well or septic. Accessory living units carry their own county caps on size, lot size, permit type and occupancy, set out in the section above; those were the county’s rules as of August 2026, and Health Department approval comes first on a well or septic lot. Separately, a stream or floodplain can pull part of the lot into a Resource Protection Area under the county’s Chesapeake Bay Preservation Ordinance, which restricts where anything goes — including a septic repair or replacement. Confirm the mapping for the specific parcel.
Almost entirely detached single-family houses on large lots — custom-built contemporary and traditional homes, classic colonials, older farmhouses and the occasional small hobby farm, most on an acre or more and many heavily wooded. Fairfax County’s Comprehensive Plan treats the area as the semi-rural northern end of the Upper Potomac Planning District; that was the plan text posted as of August 2026. Because the community filled in lot by lot rather than as one master-planned development, construction eras sit side by side, and the things that most separate one property from another are usually invisible online: the permitted septic bedroom count, where the drainfield and reserve area sit, well yield and water quality, whether a stream or floodplain pulls part of the lot into a Resource Protection Area, whether the acreage supports horses, and whether the property falls inside the Colvin Run Mill historic overlay or the half-mile lighting perimeter around the Turner Farm observatory.
Fairfax County Public Schools. As of August 2026, Great Falls addresses commonly feed Cooper Middle School and then Langley High School, with elementary assignment varying by address. Boundaries do not follow ZIP code lines. Fairfax County also finished its first comprehensive boundary review in more than forty years in this period: the School Board approved changes on January 22, 2026, they take effect in the 2026-27 school year, and the division identified some areas for extended review after that vote. So confirm any specific address with the FCPS boundary locator rather than relying on a listing sheet. Artur can confirm the pyramid serving an address you are considering.
Browse current Great Falls listings below, or call Artur Guney at (703) 402-7500. Because so much here turns on land rather than finishes, it is worth having someone pull the Fairfax County Health Department septic and well record, the plat with the drainfield and reserve area, and any RPA, historic overlay or lighting-district mapping before you write — along with a canvass for owners who might sell without listing publicly.
Which schools serve an address in Great Falls, how the feeder structure works, and the district's own boundary locator.
Schools serving Great Falls →Independent day schools serving Great Falls, where the campuses are, and which run buses — the one part of private schooling that depends on your address.
Private schools in Northern Virginia →The parks, trails, shopping and recreation around Great Falls — every venue confirmed open as of August 2026.
Parks, shopping & recreation in Great Falls →Each has its own plat history, lot pattern and association rules. 2 covered in detail:
