The Highlands at Mantua

Project description

The project site is parcel 58-2-10-001A1, comprising 2.12 acres in the City of Fairfax, Virginia. The site currently contains the Mantua Professional Center, described in project documents as underutilized office buildings in one-to-three-level structures totaling approximately 21,566 square feet. No existing residential units, current assessed value, or current on-site job count is recorded with high confidence for the parcel.

The applicant proposes to replace the existing office buildings with up to 14 townhouses. Per the most recent Master Development Plan narrative (revised April 6, 2026), the units will be three levels with an option for a roof deck, with a maximum building height not to exceed 38 feet. The site plan shows 62 total parking spaces — 28 garage and 34 surface spaces, including 32 shared spaces — per the June 2026 MDP plan sheets. The most recent narrative states approximately 48% open space overall. Tenure (for-sale versus rental) is not established in the project documents; this analysis uses rental defaults. The project is currently under review. No affordable unit commitment is recorded with high extraction confidence.

Economic effects

Based on an occupancy rate of 0.95 (range 0.90–0.97) applied to 14 proposed units, the project is estimated to yield 12.6 to 13.58 new households. Multiplying by persons-per-multifamily-unit drawn from Rutgers CUPR bedroom-mix multipliers yields an estimated 18.9 to 29.9 new residents.

New household spending is estimated using BLS Consumer Expenditure Survey 2023 figures scaled by household income and category-specific Engel elasticities. The top spending categories at central estimates are comparison retail (apparel, furnishings: $78,227–$141,003/yr), grocery ($75,654–$121,969/yr), entertainment ($64,144–$118,228/yr), and restaurants and bars ($63,106–$111,237/yr).

Spending capture by retail cluster (screening estimates). The Huff capture figures reported here are screening estimates computed via a joint destination-and-mode-choice model (P(j,m) ~ A_j × w_m × exp(−b_m × t_mj)) applied to individual retail points of interest, then aggregated to named clusters for reporting. They indicate where new spending is likely to land and are not predictions. The four clusters capturing the largest share are:

• Fairchester Drive & Hill Street: $60,738–$89,975/yr, led by grocery and comparison retail
• Mathy Drive & Pickett Road: $35,215–$78,845/yr, with entertainment contributing meaningfully alongside restaurants and comparison retail
• Chain Bridge Road & North Street: $36,748–$59,774/yr, with entertainment and restaurants as the leading sub-categories
• Blenheim Boulevard & Fairfax Boulevard: $28,112–$68,909/yr, led by restaurants and bars

The Huff model estimates that 53.4%–58.1% of all retail spending and 57.7%–65.4% of food-away-from-home spending would be captured at destinations inside the city boundary. These too are screening estimates.

Project's own retail capture. The project includes no proposed retail square footage; accordingly, the Huff model assigns zero annual capture to the project's own ground floor ($0, low $0, high $0). This figure is a screening estimate.

Foot-traffic index change. The modeled change in the foot-traffic index across the 10 nearest commercial street segments is 0.0% at the central estimate. This figure is a screening estimate derived by allocating new residents' modeled walk trips across the walk network and comparing them to a sampled baseline betweenness index; it is not calibrated against pedestrian counts.

Jobs ledger. The existing 21,566 square feet of office space implies between 43 and 86 on-site jobs displaced, computed as existing commercial square footage divided by an assumed square feet per office job (range 250–500 sq ft/job). The proposed project adds no retail or office square footage, so on-site retail jobs added is zero. The net on-site job change is estimated at −43 to −86 jobs. Residential tenure not being established, the analysis notes that for-sale product would raise the household size, income, and occupancy assumptions relative to the rental defaults used here.

Fiscal effects

Current tax base. The current real estate tax on parcel 58-2-10-001A1, computed as the current assessed value multiplied by the applicable rate, is $36,490/yr.

Projected tax base. The projected assessed value is estimated at $5,034,390 to $6,425,054, computed as 14 units multiplied by assessed value per unit drawn from three multifamily comparables in the City of Fairfax assessment database (buildings constructed 2020–2022, ranging from $359,599 to $458,932 per unit). The projected real estate tax on that value is $53,994 to $68,909/yr. The real estate tax increase above the current baseline is therefore $17,504 to $32,419/yr.

Other recurring revenues. Personal property tax on resident vehicles is estimated at $4,683 to $20,191/yr; this is explicitly a rough estimate, as neither vehicles per household nor average vehicle assessed value is observed project-specific data — the method multiplies new households by assumed vehicles per household by assumed average vehicle value by the city personal property rate, and the result should be treated as order-of-magnitude. Meals tax on in-city dining captured by the Huff model is estimated at $1,637 to $3,273/yr. Local sales tax share on in-city retail capture is estimated at $894 to $1,659/yr.

Service costs — two framings. Service costs are estimated under a marginal framing: non-school per-capita costs are multiplied by a marginal cost factor (range 0.25–0.55, central 0.35) representing the share of fixed-overhead services that actually scale with new infill residents, and school costs are computed separately as estimated K-12 students multiplied by the net local cost per pupil. At 14 units and 0.08 students per unit (range 0.05–0.12), the project is estimated to generate 0.7 to 1.68 K-12 students, producing a school-cost component of $13,972 to $33,534/yr at the $19,961 net local cost per pupil used in the model. The total service cost under this method is $38,797 to $119,864/yr.

The marginal framing deliberately excludes services that do not scale with new residents and uses a lower effective rate than a full average-cost method would produce. A full average-cost approach — which assigns each new resident the citywide average expenditure without distinguishing fixed from variable costs — would yield a higher cost estimate and therefore a more negative or less positive net result than shown here. The marginal cost factor's range (0.25–0.55) partially captures that uncertainty, but the two framings are not directly comparable.

Net fiscal impact — this analysis. Under the marginal framing, the net annual fiscal impact ranges from −$95,144 to +$18,745 (central estimate −$34,378), computed as incremental new recurring revenues minus service costs that scale with new residents.

Comparison to published staff estimates. City staff published two estimates of net annual fiscal impact for this project:

• The February 25, 2025 City Council Post-Submission Work Session Cover Memo (Bryan D. Foster, City Manager) and the accompanying Staff Report, Page 21 (Albert Frederick, Senior Planner) both state: "Staff estimate that this proposal would net a positive fiscal impact of between $24,000 and $72,000 annually with an average of $48,000."
• The July 27, 2026 Planning Commission public hearing Staff Analysis (Z-24-00236), Page 8 (Albert Frederick, Planner III) states: "Staff estimates that this proposal would net a positive fiscal impact of between $32,000 and $91,000 annually with an average of $61,500."

The range produced by this analysis (−$95,144 to +$18,745) does not overlap with either staff range ($24,000–$72,000 or $32,000–$91,000). The directional disagreement is methodological: this analysis applies a marginal cost factor (0.25–0.55) to non-school services and uses the Rutgers CUPR multifamily household-size multiplier for the school-student estimate, while the staff method is not fully described in the available documents. Differences in assumed assessed value per unit, the school-cost treatment, which revenue lines are included, and the marginal versus average cost framing are all plausible sources of the gap. The staff figures are reported here as published and are not combined with or averaged against this analysis's estimates.

Not evaluated in this version

Several analyses relevant to the full project review have not been computed in this version of the report. Specifically, the bike-lane corridor analysis, trail connectivity assessment, broader multimodal connectivity evaluation, environmental impact analysis, and comparable-places analysis are deferred and will be addressed in subsequent modules if and when those analyses are undertaken. Readers should not interpret the absence of these sections as a finding in either direction on those topics.