Tax Value per Acre

The Arnot Mall sits on 83 acres and produces $72,000 in assessed value per acre. A single apartment building on Main Street in Elmira produces $7.9 million per acre. Land is finite. How we use it is a fiscal choice.

The Minicozzi Question
Urban planner Joe Minicozzi developed a framework comparing properties not by their total assessed value, but by their value per acre of land consumed — the "miles per gallon" of fiscal productivity.
The question isn't how much a property is worth. It's how much it produces per acre of finite land — and per foot of road, water main, and sewer line required to serve it. A mall may carry a $6 million assessment, but it occupies 83 acres. A four-story downtown apartment block may carry a $5 million assessment and fit on two-thirds of an acre. The tax math is not close.

The per-acre lens matters because land is the one resource a municipality cannot expand. Infrastructure cost — roads, water, sewer, storm drains, emergency response travel time — scales with area served, not just assessment total. A development pattern that spreads the same tax base across ten times as much land produces structurally higher infrastructure costs per dollar of revenue collected.

This is not an argument against suburban development. It is an argument for pricing it honestly — and for not systematically undervaluing the fiscal productivity of the denser, older urban fabric that already exists.


What the Numbers Show
Chemung County's 2025 assessment roll, joined to the county parcel shapefile for acreage data (parcel file as of May 2025). 41,509 taxable parcels with valid acreage.
$7.9M per acre — 154 Main St, Elmira
downtown apt. block, 0.67 acres
$629K per acre — Big Flats strip ctr.
830 County Rte 64, 30 acres
$319K per acre — Elmira single-family
median of 9,506 parcels
$72K per acre — Arnot Mall
3300 Chambers Rd, 83.4 acres

The Arnot Mall at $6 million assessed value looks like a significant taxpayer in absolute terms. But it occupies 83 acres — enough land to hold roughly 450 typical Elmira single-family lots. Those 450 lots would, at the city's median single-family assessment of $55,000 per property, produce over $24 million in assessed value. The mall produces $6 million. The land is doing far less fiscal work than an equivalent footprint of urban fabric would.

Big Flats and Horseheads — the county's primary commercial growth zones — produce $288K and $254K per acre across their commercial base, respectively. Elmira's commercial parcels produce $310K per acre. The city's commercial strip is actually more fiscally productive per acre than the Route 17 corridor — even with stagnant assessments and decades without reassessment.


The Lot Size Inverse Relationship
As residential lot size grows, assessed value per acre falls sharply — and the decline is remarkably consistent across different municipalities.

A single-family home on a city lot under 0.1 acres in Elmira produces a median of $474,000 in assessed value per acre. The same type of property on a 2–5 acre rural lot produces only $40,000 per acre — a 12:1 ratio. The pattern holds across municipalities: Horseheads single-family homes on small lots produce $776K/acre; on large lots the same town's homes drop below $72K/acre.

This is structural, not a quirk of individual properties. A home worth $100,000 on a quarter-acre lot produces $400,000/acre. The same home on a two-acre lot produces $50,000/acre. The house hasn't changed. The land consumption has — and so has the infrastructure burden.

Infrastructure cost doesn't scale with assessment total — it scales with the area served. A water main running past a two-acre lot costs roughly the same per foot as one running past a quarter-acre lot. Roads don't know whether the house they front is assessed at $50,000 or $200,000. The larger the lot, the worse the ratio of infrastructure cost to tax revenue generated.

The lot-size curve is the fiscal cost of sprawl made visible. Every step rightward on the chart — toward larger lots, longer cul-de-sacs, bigger setbacks — represents less revenue extracted per unit of infrastructure committed.

Charts
Three views of per-acre productivity: landmark comparisons, the lot-size curve, and municipal totals. All data from the 2025 Chemung County assessment roll joined to county parcel shapefile acreage.
Tax Productivity per Acre — Landmark Comparisons Specific parcels (colored by type) alongside property-class medians. The Arnot Mall (83 acres, $72K/acre) sits at the bottom; downtown Elmira apartment buildings ($4M–$8M/acre) at the top. The gap is over 100:1.
The Lot-Size Inverse Curve — Single-Family Residential As residential lot size increases, assessed value per acre falls consistently across all four municipalities. Only bins with at least 10 parcels plotted. Erin (rural) starts lower and declines faster; city parcels stay productive to larger sizes because higher home values partially offset the larger lots.
Assessed Value per Acre by Municipality Median assessed value per acre for single-family residential and commercial parcels. Urban Elmira and inner suburbs (Horseheads) lead on residential productivity. Rural towns (Chemung, Erin) trail dramatically — not because homes are cheap, but because lots are large.

Source: 2025 Chemung County assessment roll (data.ny.gov 7vem-aaz7) joined to parcel acreage, compiled into per-acre.json by scripts/visualize_per_acre.py. Full method on the Data & Sources page.


Zoom In: What a Big-Box Parcel Is Actually Made Of
The same lens, applied to the region's major retailers. Two questions: how much taxable value does each square foot of their land produce, and how much of their assessed value is the building — versus just the dirt and parking under it?
Assessed Value per Square Foot of Lot Every square foot of a parcel is land the public street-and-pipe grid has to reach. Downtown row buildings produce the most value per square foot ($28); Target produces under $7. Whisker lines span the middle half of parcels in each group; the navy “(est.)” bars are single big-box parcels whose lot sizes are estimated from their land assessments (their deeds record no dimensions).
How Much of the Value Is Just the Land? Each bar is the share of a retailer's total assessment that is land rather than building. The typical county parcel is ~20% land. The Arnot Mall is 96% land: an 83-acre, $6M property whose buildings add almost nothing taxable — it is, fiscally, a parking lot. A building that adds little value still gets full roads, water, and emergency coverage to every corner of its lot.

Source: 2025 Chemung County assessment roll, compiled into land-productivity.json by scripts/visualize.py. Big-box lot sizes are estimates (land assessment ÷ $3.34/sqft, the median measured commercial land rate in the Route 17 corridor); Wegmans, in the City of Elmira, is the least reliable of these estimates.


The Map
Every parcel in the county, colored by assessed value per acre — the same "miles per gallon" measure as the charts above. Dense, productive land glows deep red; sprawl and large rural lots fade to pale yellow. Toggle a single productivity band in the layer control to isolate, say, only the $600K+/acre parcels and watch them concentrate downtown.
Tips:
  • Color = assessed value per acre (see the legend, bottom right)
  • Toggle the ★ Landmark anchors layer to find Arnot Mall ($72K/acre) and 154 Main St ($7.9M/acre) as reference points
  • Turn off the lower bands to see where the county's most fiscally productive land actually sits

Open full-screen map →


What This Means for Chemung County
The county's growth pattern — commercial and residential expansion in Big Flats, Horseheads, and Southport — is expanding the tax base while simultaneously lowering the fiscal productivity per acre of that base.

Between 2021 and 2025, Chemung County's total taxable assessed value grew by approximately $782 million. Nearly all of that growth happened in the suburban ring — in municipalities where lot sizes are larger, commercial footprints are bigger, and value per acre is structurally lower. The county is, in fiscal terms, getting more expensive to service at the same time it is growing.

The City of Elmira, by contrast, has a higher commercial value per acre than its suburban competitors — but its total assessed value has been essentially flat for years, held down by frozen assessments, a large exempt sector, and disinvestment from properties that could be producing more. The city's per-acre productivity advantage is not reflected in revenue because the underlying assessments are themselves depressed.

A citywide reassessment wouldn't change the per-acre fundamentals — downtown Elmira would still beat Big Flats strip retail on productivity per acre. But it would close the gap between what properties are worth and what they're assessed at, allowing the city to capture the revenue its land use pattern is actually capable of generating.

The per-acre data makes the case for density on fiscal grounds, not just aesthetic ones. The urban fabric that already exists in Elmira is the county's most fiscally productive land use, acre for acre. Maintaining and investing in that fabric — rather than continuing to extend infrastructure to lower-productivity suburban and rural development — is what fiscal sustainability looks like.

For the broader context on where the county's assessment growth has happened — and hasn't — see the Trends page. For the argument that reassessment is both possible and necessary to capture the city's productivity advantage, see Elmira: The Frozen Roll.