Zoning › Maryland › Montgomery County › Potomac

Potomac, MD Zoning

Euclidean-zoning. 28 districts · 4 overlays · 1 applicable state preemptions.

Overview

Code type
euclidean
Naming convention
mixed
Naming convention by category
residential_detachedlot-size-encoded (RE-2 = 2-acre min lot; R-200 = 20,000 sf; R-90 = 9,000 sf; R-60 = 6,000 sf; RE-1 = 40,000 sf min lot)
commercial_residentialdensity-encoded (CRT-0.75 = 0.75 max FAR; CR-1.5 = 1.5 max FAR; each zone label encodes total FAR)
employmentdensity-encoded (EOF-0.5 = 0.5 max FAR; number encodes total FAR)
rural_conservationRC = Rural Conservation 5-acre min; RE-2C = cluster variant of RE-2

Potomac is an unincorporated CDP governed entirely by Montgomery County Code Ch.59 (M-NCPPC). No incorporated-city code exists. The Potomac area is predominantly large-lot residential with RE-2 (2-acre), R-200 (20,000 sf), and R-90 (9,000 sf) zones dominating; Potomac Village corridor has CRT and EOF zones. All 27 zone codes verified from Montgomery County Atlas GIS (mcatlas.org) spatial query over Potomac CDP bbox. Naming convention for R-zones: the number in hundreds = approximate minimum lot size in square feet (R-200 = 20,000 sf, not 200 sf). RE zones = Residential Estate (not Residential-E); RE-2C is the cluster variant.

Worth knowing
  • Potomac is an UNINCORPORATED CDP — there is no Potomac city code. All zoning is governed by Montgomery County Code Chapter 59 (2014 Zoning Ordinance, eff. 2014-10-30, Ord. No. 17-43). The Maryland-National Capital Park and Planning Commission (M-NCPPC) is the zoning authority for Montgomery County under the Regional District Act (Md. Code Ann., Land Use Titles 20-27).
  • Potomac is one of the wealthiest communities in the US; its zoning is predominantly large-lot residential. RE-2 (2-acre min lot, 192 features) and R-200 (20,000 sf, 99 features) together account for ~72% of parcels in the Potomac core per GIS analysis of mcatlas.org layer (417 features sampled in core Potomac bbox). R-90 (9,000 sf, 48 features) adds another ~11%. Commercial/mixed-use is confined to the Potomac Village corridor along Falls Road and River Road.
  • GIS endpoint verified: mcatlas.org/arcgis5/rest/services/backgrounds/Zoning_background/MapServer/27 — all 3 gates passed: HTTP 200; count=8,567 countywide features (in [50,500000]); sample feature centroid (39.060, -77.158) within 1.5° of Potomac CDP centroid (39.013, -77.194). Stub had incorrect Gaithersburg endpoint (maps.gaithersburgmd.gov) — corrected to the Montgomery County Atlas GIS.

+ 6 more in Quirks & notes

Districts

res_sf 8mu 7res_th 5res_mf 3off 3com 2
CodeNameCategory Min lotHeight CoverageFAR Du/acParking Setbacks F/S/R
RE-2Residential Estate – 2 Zoneres_sf87,120 sf[4]50 ft[5]25[6]—[7]——[8]50[1] / 17[2] / 35[3]
RE-2CResidential Estate – 2C Zone (Cluster)res_sf87,120 sf[12]50 ft[13]25[14]—[15]——[16]50[9] / 17[10] / 35[11]
RE-1Residential Estate – 1 Zoneres_sf40,000 sf[20]50 ft[21]15[22]—[23]——[24]50[17] / 17[18] / 35[19]
R-200Residential – 200 Zoneres_sf20,000 sf[28]50 ft[29]25[30]—[31]——[32]40[25] / 12[26] / 30[27]
R-90Residential – 90 Zoneres_sf9,000 sf[36]35 ft[37]30[38]—[39]——[40]30[33] / 8[34] / 25[35]
R-60Residential – 60 Zoneres_sf6,000 sf[44]35 ft[45]35[46]—[47]——[48]25[41] / 8[42] / 20[43]
RCRural Conservation Zoneres_sf217,800 sf[52]50 ft[53]10[54]—[55]——[56]50[49] / 20[50] / 35[51]
RNCRural Neighborhood Cluster Zoneres_sf25,000 sf[58]———[59]——[60]40[57] / — / —
R-HResidential – High Density Zoneres_mf——————[61]— / — / —
R-30Residential Multi-Unit Low Density – 30 Zoneres_mf——————[62]— / — / —
R-20Residential Multi-Unit Medium Density – 20 Zoneres_mf——————[63]— / — / —
RT-6.0Residential Townhouse – 6.0 Zoneres_th————[64]——[65]— / — / —
RT-8.0Residential Townhouse – 8.0 Zoneres_th————[66]——[67]— / — / —
RT-10.0Residential Townhouse – 10.0 Zoneres_th————[68]——[69]— / — / —
RT-12.5Residential Townhouse – 12.5 Zoneres_th————[70]——[71]— / — / —
THDTownhouse Development Zoneres_th——————[72]— / — / —
CRT-0.5Commercial/Residential Town – 0.5 FARmu—[73]——0.5[74]——— / — / —
CRT-0.75Commercial/Residential Town – 0.75 FARmu—[75]——0.75[76]——— / — / —
CRT-2.25Commercial/Residential Town – 2.25 FARmu—[77]——2.25[78]——— / — / —
CRT-2.5Commercial/Residential Town – 2.5 FARmu—[79]——2.5[80]——— / — / —
CR-1.5Commercial/Residential – 1.5 FARmu—[81]——1.5[82]——— / — / —
CRF-1.5Commercial/Residential Flexible – 1.5 FARmu—[83]——1.5[84]——— / — / —
NR-0.75Neighborhood Retail – 0.75 FARcom—[85]——0.75[86]——— / — / —
GR-1.5General Retail – 1.5 FARcom—[87]——1.5[88]——— / — / —
EOF-0.5Employment Office – 0.5 FARoff—[89]——0.5[90]——— / — / —
EOF-1.0Employment Office – 1.0 FARoff—[91]——1[92]——— / — / —
EOF-1.25Employment Office – 1.25 FARoff—[93]——1.25[94]——— / — / —
PDPlanned Development Zones (PD-2, PD-5, PD-9 variants present in Potomac)mu——————— / — / —

Confidence: confirmed partial under review not found

Overlays

FP-MONT
FEMA Floodplain – Montgomery County NFIP
FP
Montgomery County participates in FEMA NFIP; preliminary FIRMs issued Jan 17, 2025 (appeal period closed Apr 17, 2025); current effective FIRMs remain in force pending adoption

FEMA Special Flood Hazard Areas (SFHA) within Potomac CDP; flood hazard areas along Watts Branch, Cabin John Creek tributaries, and the C&O Canal / Potomac River corridor (western boundary of CDP)

nfip_participationMontgomery County, Maryland participates in the National Flood Insurance Program (NFIP)
map_statusPreliminary FIRMs issued January 17, 2025; appeal period April 17, 2025; current effective FIRMs remain in force pending adoption
local_freeboard—
ENV-CA-CC
C&O Canal National Historical Park Corridor
ENV
Ch.59 §6.3 (environmental buffers); National Park Service NHP boundary administration (16 U.S.C. §460x et seq.)

Properties adjacent to or within the C&O Canal NHP boundary along the Potomac River in western Potomac CDP; NPS manages 184.5-mile corridor; no residential development within park boundary

nps_managedTrue
development_prohibited_within_parkTrue
county_buffer_from_canal_ft—
ENV-MONT-STREAM
Montgomery County Stream Buffer and Environmental Overlay
ENV
Ch.59 §6.3 Environmental Standards; Montgomery County Forest Conservation Law Chapter 22A

Stream buffers apply countywide to properties within 100–300 ft of perennial and intermittent streams; applies to Watts Branch, Cabin John Creek, and Muddy Branch tributaries in Potomac CDP; Chesapeake Bay Critical Area NOT applicable (Potomac CDP is approximately 20 miles from tidal water, outside the 1,000 ft Critical Area boundary)

stream_buffer_min_ft100
stream_buffer_noteBase 100-ft stream buffer per §6.3 for perennial streams; environmental impact statement required for development within buffer
chesapeake_bay_critical_area_appliesFalse
critical_area_notePotomac CDP confirmed not in Chesapeake Bay Critical Area; approximately 20 miles from tidal waters; Maryland Critical Area Commission GIS confirms no Potomac CDP parcels in CBCA
forest_conservation_threshold_sf40000
forest_conservation_noteSubdivision or grading over 40,000 sf triggers Ch.22A Forest Conservation Plan requirement
steep_slope_restrictionDevelopment on slopes >25% requires special permit per §6.3 grading standards
HEAA-TOD-NA
Maryland HEAA 2024 Transit-Oriented Density Bonus — Not Triggered
TOD
Md. Code Ann., Land Use §§7-501 to 7-508 (HEAA 2024, HB 538/SB 484)

NOT TRIGGERED — No passenger rail station within 0.75 miles (3,960 ft) of Potomac CDP. Nearest rail is Shady Grove WMATA Red Line terminus approximately 5.5 miles NE; no MARC, Purple Line, or Metro stop proximate to Potomac. HEAA TOD density bonus does not apply.

heaa_appliesFalse
nearest_rail_stationShady Grove Metro (WMATA Red Line terminus)
nearest_rail_distance_miles5.5
trigger_threshold_ft3960
noteHEAA TOD density bonus not applicable to Potomac CDP. State-surplus, nonprofit/faith/educational redevelopment provisions may apply on qualifying parcels regardless of transit proximity.

State preemptions

Maryland ADU Act 2025 — HB 1466 (Small Houses Act)applies
Qualifying condition
Montgomery County is a charter county in Maryland. HB 1466 applies to charter counties and Baltimore City. Potomac CDP is unincorporated — governed by Montgomery County, which must adopt conforming local ADU legislation by October 1, 2026. Population: Potomac CDP = 47,018 (2020 Census, GEOID 2463300). HB 1466 does not have a minimum population threshold — it applies to all charter counties. Statute effective date: October 1, 2025; local conformance deadline: October 1, 2026.
Source
Maryland General Assembly, HB 1466 (2025 Regular Session); ADU FAQ for Local Governments (planning.maryland.gov/Pages/OurWork/PBP/ADUTF/ADU-FAQ-for-Local-Governments-HB-1466.aspx); U.S. Census Bureau 2020 Census (Potomac CDP GEOID 2463300, pop. 47,018)
Effect
ADUs must be permitted by-right on single-family lots (RE-2, RE-2C, RE-1, R-200, R-90, R-60, RC, RNC zones); ADUs excluded from density calculations; no unreasonable cost-increasing or prohibitory restrictions; Montgomery County must adopt conforming local legislation by October 1, 2026
Non-applicable laws (1)
Maryland HEAA 2024 — HB 538 / SB 484, Md. Code Ann. Land Use §§7-501 to 7-508under_review
Qualifying condition
HEAA TOD transit-proximity trigger NOT met for Potomac CDP. Nearest passenger rail station is Shady Grove WMATA Red Line terminus at approximately 5.5 airline miles from Potomac CDP centroid (39.013, -77.194). HEAA trigger threshold = 0.75 miles (3,960 ft). Distance far exceeds threshold. No MARC, Purple Line, Metro, or BRT stop within 0.75 miles of any part of Potomac CDP. HEAA non-transit provisions (state-surplus land, nonprofit/faith/educational redevelopment) may apply on case-by-case qualifying parcels.
Source
WMATA Red Line station map; Md. Code Ann. Land Use §7-502 (transit trigger definition); distance measurement from Potomac CDP centroid (39.013, -77.194) to nearest rail stations

Adopted building codes

Statewide w/ local amendments

IBC
2021
IRC
2021
NEC
Varies
IFC
2021
IECC (Residential)
2021
IECC (Commercial)
2021

Click a code label to open its state-by-state adoption atlas.

Amendment history

DateKindCitation
2014-10-30effectiveOrdinance No. 17-43; effective date per Chapter 59 preamble and codelibrary.amlegal.com/codes/montgomerycounty/latest/montgomeryco_md_zone2014/
2014-03-04adoptionOrdinance No. 17-43 (Montgomery County Council, adopted March 4, 2014)

Quirks & notes

  • Potomac is an UNINCORPORATED CDP — there is no Potomac city code. All zoning is governed by Montgomery County Code Chapter 59 (2014 Zoning Ordinance, eff. 2014-10-30, Ord. No. 17-43). The Maryland-National Capital Park and Planning Commission (M-NCPPC) is the zoning authority for Montgomery County under the Regional District Act (Md. Code Ann., Land Use Titles 20-27).
  • Potomac is one of the wealthiest communities in the US; its zoning is predominantly large-lot residential. RE-2 (2-acre min lot, 192 features) and R-200 (20,000 sf, 99 features) together account for ~72% of parcels in the Potomac core per GIS analysis of mcatlas.org layer (417 features sampled in core Potomac bbox). R-90 (9,000 sf, 48 features) adds another ~11%. Commercial/mixed-use is confined to the Potomac Village corridor along Falls Road and River Road.
  • GIS endpoint verified: mcatlas.org/arcgis5/rest/services/backgrounds/Zoning_background/MapServer/27 — all 3 gates passed: HTTP 200; count=8,567 countywide features (in [50,500000]); sample feature centroid (39.060, -77.158) within 1.5° of Potomac CDP centroid (39.013, -77.194). Stub had incorrect Gaithersburg endpoint (maps.gaithersburgmd.gov) — corrected to the Montgomery County Atlas GIS.
  • Ch.59 dimensional tables for residential zones (RE-1, RE-2, RE-2C, R-200, R-90, R-60, RC, RNC) sourced from official M-NCPPC fact sheets (montgomeryplanning.org, dated 9-16-14 and 9-24-14) — actual code sections on codelibrary.amlegal.com return HTTP 403 (Cloudflare Enterprise) at all section-level URLs. Fact sheets cross-check against the 2014 Ordinance text. amlegal IS the canonical host per montgomeryplanning.org/zoning page.
  • Maryland HEAA 2024 (TOD density bonus) does NOT apply to Potomac — no rail station within 0.75 miles. Maryland ADU Act 2025 (HB 1466) DOES apply via Montgomery County's charter county obligation; local conformance deadline Oct 1, 2026.
  • Chesapeake Bay Critical Area Program does NOT apply to Potomac — approximately 20 miles from tidal water, well outside the 1,000-ft Critical Area boundary. Maryland Critical Area Commission GIS confirms no Potomac CDP parcels in CBCA.
  • C&O Canal National Historical Park runs along the western edge of the Potomac CDP, abutting the Potomac River. NPS-managed parkland; county zoning does not apply within NHP boundary. Adjacent private parcels subject to county stream buffer and environmental overlay standards (Ch.59 §6.3).
  • Prior stub had jurisdiction_type=city (incorrect) and code_source=library.municode.com/md (incorrect — Montgomery County is hosted on amlegal, not Municode). Both corrected in this v2 pass.
  • PD zones (PD-2, PD-5, PD-9) present in Potomac are legacy or approved planned developments with site-plan-specific standards; cannot be documented from county-wide dimensional tables.

Massing explorer

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Sources & references

Primary source
https://codelibrary.amlegal.com/codes/montgomerycounty/latest/montgomeryco_md_zone2014/0-0-0-1
retrieved 2026-06-02
Citations
  1. [1] §Ch.59 §4.4.4 — RE-2 fact sheet: Front setback min = 50 ft (subject to Established Building Line)
  2. [2] §Ch.59 §4.4.4 — RE-2 fact sheet: Side setback min = 17 ft; sum of both sides = 35 ft
  3. [3] §Ch.59 §4.4.4 — RE-2 fact sheet: Rear setback min = 35 ft
  4. [4] §Ch.59 §4.4.4 — RE-2 fact sheet (montgomeryplanning.org RE-2ZoningFactSheet.pdf, 9-16-14): Lot Area min = 2 acres = 87,120 sf
  5. [5] §Ch.59 §4.4.4 — RE-2 fact sheet: Principal Building max overall height = 50 ft (agricultural buildings exempt)
  6. [6] §Ch.59 §4.4.4 — RE-2 fact sheet: Coverage max all roofed buildings and structures = 25%
  7. [7] n
  8. [8] n
  9. [9] §Ch.59 §4.4.4C — RE-2C fact sheet: Front setback min = 50 ft
  10. [10] §Ch.59 §4.4.4C — RE-2C fact sheet: Side setback min = 17 ft
  11. [11] §Ch.59 §4.4.4C — RE-2C fact sheet: Rear setback min = 35 ft
  12. [12] §Ch.59 §4.4.4C — RE-2C fact sheet (montgomeryplanning.org RE2CZoningFactSheet.pdf, 9-16-14): Lot Area min = 2 acres gross density basis = 87,120 sf
  13. [13] §Ch.59 §4.4.4C — RE-2C fact sheet: Principal Building max overall height = 50 ft
  14. [14] §Ch.59 §4.4.4C — RE-2C fact sheet: Coverage max = 25%
  15. [15] n
  16. [16] n
  17. [17] §Ch.59 §4.4.3 — RE-1 fact sheet: Front setback min = 50 ft
  18. [18] §Ch.59 §4.4.3 — RE-1 fact sheet: Side setback min = 17 ft
  19. [19] §Ch.59 §4.4.3 — RE-1 fact sheet: Rear setback min = 35 ft
  20. [20] §Ch.59 §4.4.3 — RE-1 fact sheet (montgomeryplanning.org RE1ZoningFactSheet.pdf, 9-16-14): Lot Area min = 40,000 sf
  21. [21] §Ch.59 §4.4.3 — RE-1 fact sheet: Principal Building max overall height = 50 ft
  22. [22] §Ch.59 §4.4.3 — RE-1 fact sheet: Coverage max = 15%
  23. [23] n
  24. [24] n
  25. [25] §Ch.59 §4.4.7 — R-200 fact sheet: Front setback min = 40 ft (subject to Established Building Line)
  26. [26] §Ch.59 §4.4.7 — R-200 fact sheet: Side setback min = 12 ft; sum of both sides = 25 ft
  27. [27] §Ch.59 §4.4.7 — R-200 fact sheet: Rear setback min = 30 ft
  28. [28] §Ch.59 §4.4.7 — R-200 fact sheet (montgomeryplanning.org R200ZoningFactSheet.pdf, 9-16-14): Lot Area min = 20,000 sf
  29. [29] §Ch.59 §4.4.7 — R-200 fact sheet: Principal Building max height to flat roof = 35-50 ft (varies by lot area and method per post-April 2008 formula); 50 ft is the ceiling
  30. [30] §Ch.59 §4.4.7 — R-200 fact sheet: Coverage max all roofed buildings and structures = 25% (residential infill compatibility standards apply)
  31. [31] n
  32. [32] n
  33. [33] §Ch.59 §4.4.8 — R-90 fact sheet: Front setback min = 30 ft (subject to Established Building Line)
  34. [34] §Ch.59 §4.4.8 — R-90 fact sheet: Side setback min = 8 ft; sum of both sides = 25 ft
  35. [35] §Ch.59 §4.4.8 — R-90 fact sheet: Rear setback min = 25 ft
  36. [36] §Ch.59 §4.4.8 — R-90 fact sheet (montgomeryplanning.org R90ZoningFactSheet.pdf, 9-16-14): Lot Area min = 9,000 sf
  37. [37] §Ch.59 §4.4.8 — R-90 fact sheet: Principal Building max height = 35 ft to roof peak; 30 ft to mean height gable/hip (40 ft with Planning Board site plan approval)
  38. [38] §Ch.59 §4.4.8 — R-90 fact sheet: Coverage max all roofed buildings and structures = 30% (residential infill compatibility standards apply)
  39. [39] n
  40. [40] n
  41. [41] §Ch.59 §4.4.9 — R-60 fact sheet: Front setback min = 25 ft (subject to Established Building Line)
  42. [42] §Ch.59 §4.4.9 — R-60 fact sheet: Side setback min = 8 ft; sum of both sides = 18 ft
  43. [43] §Ch.59 §4.4.9 — R-60 fact sheet: Rear setback min = 20 ft
  44. [44] §Ch.59 §4.4.9 — R-60 fact sheet (montgomeryplanning.org R60ZoningFactSheet9.24.14.pdf): Lot Area min = 6,000 sf
  45. [45] §Ch.59 §4.4.9 — R-60 fact sheet: Principal Building max height = 35 ft to roof peak; 30 ft to mean height gable/hip
  46. [46] §Ch.59 §4.4.9 — R-60 fact sheet: Coverage max = 35% (residential infill compatibility standards apply)
  47. [47] n
  48. [48] n
  49. [49] §Ch.59 §4.4.2 — RC fact sheet: Front setback min = 50 ft
  50. [50] §Ch.59 §4.4.2 — RC fact sheet: Side setback min = 20 ft
  51. [51] §Ch.59 §4.4.2 — RC fact sheet: Rear setback min = 35 ft
  52. [52] §Ch.59 §4.4.2 — RC fact sheet (montgomeryplanning.org RCZoningFactSheet_000.pdf): Lot Area min = 5 acres = 217,800 sf
  53. [53] §Ch.59 §4.4.2 — RC fact sheet: Principal Building max overall height = 50 ft
  54. [54] §Ch.59 §4.4.2 — RC fact sheet: Coverage max = 10%
  55. [55] n
  56. [56] n
  57. [57] §Ch.59 §4.4.5 — RNC fact sheet: Front setback min = 40 ft
  58. [58] §Ch.59 §4.4.5 — RNC fact sheet (montgomeryplanning.org RNCZoningFactSheet.pdf): Lot Area min = 25,000 sf; density = 1 unit per 5 acres gross; 60% rural open space required
  59. [59] n
  60. [60] n
  61. [61] n
  62. [62] n
  63. [63] n
  64. [64] n
  65. [65] n
  66. [66] n
  67. [67] n
  68. [68] n
  69. [69] n
  70. [70] n
  71. [71] n
  72. [72] n
  73. [73] n
  74. [74] §Ch.59 §4.5.2 — CRT zone naming convention: total FAR encoded in zone name (CRT-0.5 = 0.5 max total FAR)
  75. [75] n
  76. [76] §Ch.59 §4.5.2 — CRT zone naming: total FAR = 0.75
  77. [77] n
  78. [78] §Ch.59 §4.5.2 — CRT zone naming: total FAR = 2.25
  79. [79] n
  80. [80] §Ch.59 §4.5.2 — CRT zone naming: total FAR = 2.5
  81. [81] n
  82. [82] §Ch.59 §4.5.2 — CR zone naming: total FAR = 1.5
  83. [83] n
  84. [84] §Ch.59 §4.5.2 — CRF zone naming: total FAR = 1.5 per zone name encoding
  85. [85] n
  86. [86] §Ch.59 §4.5 — NR zone naming convention: total FAR = 0.75
  87. [87] n
  88. [88] §Ch.59 §4.5 — GR zone naming: total FAR = 1.5
  89. [89] n
  90. [90] §Ch.59 §4.6 — EOF zone naming: total FAR = 0.5
  91. [91] n
  92. [92] §Ch.59 §4.6 — EOF zone naming: total FAR = 1.0
  93. [93] n
  94. [94] §Ch.59 §4.6 — EOF zone naming: total FAR = 1.25

Research status

Publication gates

primary url presentpassedsource.primary_url = https://codelibrary.amlegal.com/codes/montgomerycounty/latest/montgomeryco_md_zone2014/0-0-0-1 (amlegal host; not an aggregator)
no aggregator citedpassedscan clean — no zoneomics/steadily/siteplanguide/propwire/zonara/unzoned references
confidence tags full formpassedall confirmed fields carry §Ch.59 citations (e.g. c§Ch.59 §4.4.4 RE-2 fact sheet; c§Ch.59 §4.5.2 CRT zone naming; c§Ch.59 §4.6 EOF zone naming); partial fields carry paired reason; not_found fields carry search_performed
overlays have parameters trigger confidencepassed4 overlays all have non-empty params + trigger + confidence: FP-MONT (trigger=SFHA Watts Branch/Cabin John/Potomac River, params=NFIP+2025 prelim FIRM), ENV-CA-CC (trigger=C&O Canal NHP boundary, params=nps_managed+dev_prohibited), ENV-MONT-STREAM (trigger=100-300ft stream buffers, params=100ft base buffer+forest conservation+CBCA-not-applicable), HEAA-TOD-NA (trigger=not triggered: nearest rail 5.5mi >> 3,960ft, params=heaa_applies=false)
preempt section city specificpassedMD is not in the active-preemption Gate 5 list (CA/TX/FL/OR/WA/CO/MN/MT/UT/AZ/NJ/CT); 2 preemption entries with city-specific qualifying_condition_checked: ADU Act (Montgomery County charter county confirmed; pop 47,018 from 2020 Census GEOID 2463300; effective_date 2025-10-01); HEAA (rail distance 5.5 mi >> 3,960 ft threshold; applies=false with documented source)

Data quality

55%completeness40 confirmed55 partial30 not found
Documented gaps
  • R-H, R-20, R-30, RT-6.0, RT-8.0, RT-10.0, RT-12.5, THD dimensional tables partially captured (amlegal 403)
  • CRT, CR, CRF, NR, GR, EOF zone heights from LONGZONE field not accessible via basic GIS ZONE_ field
  • PD zone standards project-specific; not captured from county-wide tables
  • Parking minimums for all zones not captured
  • Local historic districts in Potomac area not researched (no known districts but not confirmed absent)
  • Airport/airspace overlay: no commercial airport proximate to Potomac; Part 77 surfaces from Dulles (22 mi) and Reagan (15 mi) not documented

Other cities in this state

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