severance-damages-quantification

Calculating loss of value to remainder parcels (subset of partial taking expertise). This skill provides deep, focused methodology for quantifying specific types of severance damages - NOT general partial taking theory.

Quantifying reduced access value from loss of frontage, circuitous access, or landlocked conditions.

Direct Frontage Loss ($/Linear Foot by Road Classification)

Methodology: Value contribution of road frontage analyzed by linear foot based on road classification and development potential.

Highway frontage (400-series, divided highway):

• Commercial development potential: $500-$1,500/linear foot
• Industrial development potential: $300-$800/linear foot
• Residential development potential: $150-$400/linear foot

Arterial road (4+ lanes, signalized intersections):

• Commercial: $300-$800/linear foot
• Industrial: $200-$500/linear foot
• Residential: $100-$250/linear foot

Collector road (2-4 lanes, local significance):

• Commercial: $150-$400/linear foot
• Industrial: $100-$300/linear foot
• Residential: $50-$150/linear foot

Local road (2 lanes, residential access):

• Residential: $25-$75/linear foot
• Agricultural: $10-$30/linear foot

Example calculation:

• Before: 200 acres with 800 linear feet of highway frontage, valued at $40,000/acre = $8,000,000 total
• After taking: Highway widening takes 50-foot strip along entire frontage, removing all direct highway access
• Frontage value component: 800 LF × $600/LF (industrial development) = $480,000
• Remainder value: $8,000,000 - $480,000 (frontage premium) = $7,520,000 baseline + frontage loss
• Severance damage: $480,000 for loss of direct highway access

Circuitous Access (Time-Distance Modeling, Traffic Counts)

Methodology: Quantify value loss from increased travel time/distance to reach remainder parcel after taking eliminates direct access.

Time-distance modeling:

• Measure travel time before and after taking
• Apply value-of-time metric (typically $25-$50/hour for commercial/industrial users)
• Capitalize annual time cost to determine value loss

Example (industrial property):

• Before: Direct access to arterial road, 2-minute travel to highway interchange
• After: Taking eliminates direct access, requires 3 km detour via local roads, 8-minute travel to highway
• Additional time: 6 minutes each way = 12 minutes/day
• Annual time cost: 250 business days × 12 min/day × (1 hr/60 min) × $40/hr × 20 trips/day = $40,000/year
• Capitalization: $40,000 ÷ 7% cap rate = $571,000 severance damage

Traffic count impact:

• Loss of high-traffic frontage reduces commercial visibility
• Quantified as percentage reduction in sales/rent potential
• Example: Commercial property loses 15,000 vehicles/day frontage, gains 3,000 vehicles/day frontage → 80% traffic loss → 10-20% reduction in rent potential → capitalized value loss

Landlocked Parcel Remedies (Easement Costs, Value Impact)

Scenario: Partial taking severs access, creating landlocked remainder with no legal access to public road.

Remedies and costs:

1. Acquire access easement from adjacent landowner:

- Easement value: 10-15% of fee simple value for affected land

- Legal costs: $15K-$30K

- Survey and registration: $5K-$10K

- Total cost: Easement value + $20K-$40K transaction costs

1. Necessity easement (court-ordered):

- Legal proceedings: $50K-$150K

- Court-awarded easement compensation: 10-15% of fee simple

- Delay and uncertainty (1-3 years)

- Total cost: Easement value + $50K-$150K legal fees + time cost

1. Value impact if no easement obtainable:

- Landlocked land: 50-80% reduction in value (agricultural use only via aerial/helicopter access for specialty crops)

- Effectively sterilized for most development purposes

Example calculation:

• Remainder: 50 acres, agricultural use, $15,000/acre = $750,000
• Access loss: Landlocked, requires 200-meter easement across adjacent property
• Easement cost: 0.5 acres × $15,000/acre × 12% = $900 + $25,000 legal/survey = $25,900
• Alternatively - value loss if no easement: $750,000 × 60% reduction = $450,000 (use lower if easement obtainable, higher if not)
• Severance damage: $25,900 (cost-to-cure) or $450,000 (value loss if no cure)

Valuing odd-shaped remainders resulting from takings that create inefficient parcel configurations.

Geometric Efficiency Ratios (Area to Perimeter)

Methodology: Quantify shape inefficiency using area-to-perimeter ratio, comparing before/after taking.

Optimal shapes (efficient for development):

• Square: Area/Perimeter ratio = L²/4L = L/4 (maximum efficiency for rectangle)
• Circle: Area/Perimeter ratio = πr²/2πr = r/2 (theoretical maximum efficiency)
• Regular rectangle (2:1 ratio): Moderately efficient

Inefficient shapes:

• Long, narrow strip (10:1+ ratio): Very inefficient
• Triangular: Moderate inefficiency
• Irregular polygon (multiple angles, re-entrants): High inefficiency

Efficiency index calculation:

• Efficiency Index = (Actual Area ÷ Actual Perimeter) ÷ (Square Area ÷ Square Perimeter)
• Index = 1.0 = Perfect square efficiency
• Index = 0.8-1.0 = High efficiency (minimal value loss)
• Index = 0.6-0.8 = Moderate efficiency (5-10% value loss)
• Index = 0.4-0.6 = Low efficiency (10-20% value loss)
• Index <0.4 = Very low efficiency (20-40% value loss)

Example:

• Before: 100-acre parcel, roughly square (2,000 ft × 2,000 ft), perimeter = 8,000 LF

- Efficiency Index = (100 acres ÷ 8,000 LF) ÷ (100 acres ÷ 8,000 LF) = 1.0

• After: 60-acre remainder, long narrow strip (400 ft × 6,000 ft), perimeter = 12,800 LF

- Efficiency Index = (60 acres ÷ 12,800 LF) ÷ (Square 60 acres ÷ 7,760 LF) = 0.61

• Shape inefficiency: Moderate (0.6-0.8 range) → 8% value reduction
• Severance damage: 60 acres × $15,000/acre × 8% = $72,000

Development Yield Analysis (Buildable Area Calculations)

Methodology: Calculate reduction in developable units/area from shape constraints.

Residential subdivision example:

Before:

• 50 acres, regular shape, medium-density zoning (10 units/acre)
• Developable area: 50 acres - 15% (roads/parks) = 42.5 acres
• Yield: 42.5 acres × 10 units/acre = 425 units
• Value: 425 units × $150,000/unit = $63.75M

After (taking creates irregular remainder):

• 35 acres, irregular "L" shape with two narrow arms
• Developable area: 35 acres - 20% (roads/parks - higher % due to irregular layout) = 28 acres
• Inefficient lot layout: Many lots sub-standard depth or width
• Yield: 28 acres × 8 units/acre (reduced density) = 224 units
• Value: 224 units × $150,000/unit = $33.6M

Severance damage calculation:

• Before (proportionate): $63.75M × (35 acres ÷ 50 acres) = $44.625M
• After: $33.6M
• Severance damage: $44.625M - $33.6M = $11.025M (24.7% reduction)

Alternative methodology (per-acre impact):

• Before: $63.75M ÷ 50 acres = $1,275,000/acre
• After: $33.6M ÷ 35 acres = $960,000/acre
• Severance damage: ($1,275,000 - $960,000) × 35 acres = $11.025M

Comparable Sales of Irregular Parcels

Methodology: Market extraction showing discount for irregular shapes.

Paired sales:

Sale 1 (regular shape):

• 20 acres, square configuration, zoned commercial
• Sale price: $80,000/acre = $1,600,000

Sale 2 (irregular shape):

• 22 acres, long narrow strip (300 ft × 3,200 ft), zoned commercial
• Sale price: $65,000/acre = $1,430,000
• Time/location adjusted: $66,500/acre

Shape discount: ($80,000 - $66,500) ÷ $80,000 = 16.9% reduction for irregular shape

Application to subject:

• Remainder: 40 acres, irregular after taking
• Comparable irregular sales: 15-20% discount
• Adopted shape discount: 17%
• Fee simple value (if regular): $80,000/acre
• Actual value (irregular): $80,000 × (1 - 0.17) = $66,400/acre
• Severance damage: $80,000 - $66,400 = $13,600/acre × 40 acres = $544,000

Functional obsolescence from division - loss of highest and best use or reduced development potential.

Loss of Highest and Best Use (Zoning-Permitted vs. Achievable)

Scenario: Taking reduces parcel size below minimum for zoning-permitted use, forcing less valuable use.

Example (industrial subdivision):

Before:

• 100 acres, zoned "Employment - Prestige Industrial"
• Minimum lot size: 5 acres per zoning
• Highest and best use: Subdivision into 18 × 5-acre lots (10% for roads)
• Value: 18 lots × $500,000/lot = $9,000,000 ($90,000/acre)

After:

• 65 acres remain (35 acres taken for highway)
• Still zoned "Employment - Prestige Industrial"
• Problem: Irregular shape yields only 10 × 5-acre lots (instead of proportionate 11.7 lots)
• Alternative use: General industrial (no minimum lot size) at lower value

- Value as general industrial: 65 acres × $60,000/acre = $3,900,000

- Value if could maintain prestige industrial subdivision: 11.7 lots × $500,000 = $5,850,000

Severance damage: $5,850,000 (proportionate before value) - $3,900,000 (after value) = $1,950,000 (33% reduction)

Reduced Development Potential (Unit Count, Parking Ratios)

Scenario: Taking creates site constraints that reduce developable area or building footprint.

Example (commercial development):

Before:

• 10 acres, regular rectangle, highway frontage, zoned commercial
• Maximum lot coverage: 40%
• Parking requirement: 4 spaces/1,000 sq ft GLA
• Buildable area: 10 acres × 40% = 4 acres = 174,240 sq ft
• Parking demand: 174,240 ÷ 1,000 × 4 = 697 spaces
• Parking area: 697 spaces × 350 sq ft/space = 243,950 sq ft = 5.6 acres
• Site capacity: 174,240 sq ft building + 243,950 sq ft parking = 9.6 acres (fits)
• Value: 174,240 sq ft × $250/sq ft = $43.56M

After:

• 7 acres remain (irregular "L" shape after 3-acre corner taking)
• Buildable area still 40% coverage = 2.8 acres = 121,968 sq ft (theoretical)
• Problem: Irregular shape constrains building footprint to 90,000 sq ft maximum
• Parking demand: 90,000 ÷ 1,000 × 4 = 360 spaces
• Parking area: 360 spaces × 350 sq ft = 126,000 sq ft = 2.9 acres
• Total requirement: 90,000 sq ft building (2.07 acres) + 2.9 acres parking = 4.97 acres (fits, but reduced from potential)
• Value: 90,000 sq ft × $250/sq ft = $22.5M

Severance damage calculation:

• Before (proportionate): $43.56M × (7 acres ÷ 10 acres) = $30.49M
• After: $22.5M
• Severance damage: $30.49M - $22.5M = $7.99M (26% reduction)

Site Servicing Complications (Utilities, Drainage)

Scenario: Taking severs utility connections or disrupts drainage patterns, requiring costly remediation.

Utility relocation costs:

• Water main relocation: $300-$600/linear meter
• Sanitary sewer relocation: $500-$1,000/linear meter
• Electrical distribution: $200-$400/linear meter
• Gas main: $150-$350/linear meter

Example:

• Taking severs water and sewer connections to remainder
• Requires 400 meters of new water/sewer mains to reconnect
• Cost: 400m × $500/m (water) + 400m × $800/m (sewer) = $520,000

Drainage disruption:

• Taking alters grading, creating ponding/flooding on remainder
• Requires new storm sewer system or grading modifications
• Cost: Engineering $15K + construction $180K = $195,000

Total site servicing severance: $520,000 + $195,000 = $715,000

Agricultural severance impacts from field division, equipment access complications, and irrigation system impacts.

Field Division Costs (Fence Installation, Drainage Modifications)

Fencing costs (to separate taking from remainder):

• Agricultural fence (4-strand barbed wire): $8-$12/linear meter
• Page wire fence (livestock): $15-$25/linear meter
• Chain link fence (6-foot, industrial): $80-$120/linear meter

Example:

• Taking bisects farm, requires 2,000 meters of new fence
• Livestock operation requires page wire
• Fencing cost: 2,000m × $20/m = $40,000

Drainage modifications:

• Taking disrupts tile drainage system serving 50 acres
• Requires new outlet and 1,500 meters of tile drainage to reconnect
• Cost: Engineering $8K + tile installation $15/m × 1,500m = $30,500

Total field division costs: $40,000 + $30,500 = $70,500

Equipment Access Complications (Turning Radius, Crossing Points)

Scenario: Taking creates narrow or landlocked fields requiring circuitous equipment access.

Time-cost analysis:

• Before: 200-acre farm, efficient field layout, 2 large fields
• After: Taking bisects farm into two 100-acre parcels separated by highway
• Equipment crossing: Requires 5 km detour to move equipment between fields (no at-grade crossing)
• Annual time cost: 30 crossings/year × 5 km detour × 2 ways × 10 km/hr speed × $150/hr equipment+operator = $2,250/year
• Capitalization: $2,250 ÷ 7% cap rate = $32,140

Turning radius constraints:

• Narrow remainder field (150 meters wide) constrains large equipment
• Reduces efficiency by 15% (measured in time per acre)
• Annual cost: 50 acres × $40/acre operating cost × 15% = $300/year
• Capitalization: $300 ÷ 7% = $4,280

Total equipment access severance: $32,140 + $4,280 = $36,420

Irrigation System Impacts (Pivot Circles, Distribution Lines)

Center pivot irrigation disruption:

Scenario: Taking bisects irrigated field, disrupting center pivot system.

Before:

• 160-acre field, 4 center pivots (40 acres each)
• Irrigation value: $2,000/acre premium for irrigated land
• Total irrigation premium: 160 acres × $2,000/acre = $320,000

After:

• Taking removes 30 acres, severs distribution lines to 2 pivots
• Remaining 130 acres: 2 pivots functional (80 acres), 2 pivots non-functional (50 acres)
• Non-functional pivots: Requires $180,000 to relocate distribution lines, pump station
• Alternatives:

1. Repair irrigation: $180,000 cost to reconnect → 130 acres irrigated

2. Abandon irrigation: 50 acres lose irrigation premium → $100,000 value loss

Severance damage (cost-to-cure): $180,000 (cost to repair irrigation system)

Alternative severance damage (value loss if not repaired):

• Lost irrigation premium: 50 acres × $2,000/acre = $100,000
• Plus inefficiency/loss on remaining pivots: $20,000
• Total: $120,000

Adopt lower: $120,000 severance damage (value loss approach, as owner may not repair)

---

This skill includes a production-grade severance damages calculator with modular architecture.

Command Line Usage

```bash

# Basic calculation

python severance_calculator.py input.json

# Specify output location

python severance_calculator.py input.json results.json

# Validate input first (recommended)

python validate_severance.py input.json

python validate_severance.py input.json --fix --output clean.json

python severance_calculator.py clean.json results.json

```

Python API

```python

from severance_calculator import calculate_severance_damages, load_from_json

# Load from JSON

property_before, taking, remainder, market = load_from_json("input.json")

# Calculate

summary = calculate_severance_damages(

property_before, taking, remainder, market

)

# Access results

print(f"Total severance damages: ${summary.total_severance_damages:,.2f}")

print(f"Access damages: ${summary.access_damages.total_access_damages:,.2f}")

print(f"Shape damages: ${summary.shape_damages.total_shape_damages:,.2f}")

print(f"Utility damages: ${summary.utility_damages.total_utility_damages:,.2f}")

print(f"Farm damages: ${summary.farm_damages.total_farm_damages:,.2f}")

```

Input Format

See severance_input_schema.json for complete schema. Minimal example:

```json

{

"property_before": {

"total_acres": 10.0,

"frontage_linear_feet": 500.0,

"road_classification": "highway",

"shape_ratio_frontage_depth": 0.25,

"value_per_acre": 150000.0,

"use": "commercial"

},

"taking": {

"area_taken_acres": 1.5,

"frontage_lost_linear_feet": 100.0,

"creates_landlocked": false,

"creates_irregular_shape": true

},

"remainder": {

"acres": 8.5,

"frontage_remaining_linear_feet": 400.0,

"shape_ratio_frontage_depth": 0.20,

"access_type": "direct"

},

"market_parameters": {

"cap_rate": 0.07

}

}

```

Calculator Architecture

Modular Structure (Version 2.0.0):

```

severance-damages-quantification/

├── config/ # Centralized constants (zero magic numbers)

│ └── constants.py

├── damages/ # Specialized calculation modules

│ ├── access.py # Access impairment (frontage, circuitous, landlocked)

│ ├── shape.py # Shape irregularity (efficiency, buildable area, yield)

│ ├── utility.py # Utility impairment (site servicing, development)

│ └── farm.py # Farm disruption (fencing, equipment, irrigation)

├── models/ # Data structures

│ ├── property_data.py

│ ├── damage_results.py

│ └── market_parameters.py

├── utils/ # Shared utilities (safe_divide, capitalize_annual_cost)

│ └── calculations.py

├── tests/fixtures/ # Test scenarios

├── severance_calculator.py # Main orchestrator (360 lines, was 943)

├── severance_input_schema.json # JSON Schema validation

└── validate_severance.py # Input validation with auto-fix

```

Sample Scenarios

The calculator includes 5 tested scenarios in tests/fixtures/:

1. highway_frontage_loss.json - Highway frontage reduction (industrial)
2. landlocked_parcel.json - Complete access loss requiring easement
3. irregular_shape.json - Severe shape inefficiency from partial taking
4. farm_bisection.json - Agricultural corridor impact with field division
5. combined_damages.json - Multiple damage categories simultaneously

Key Features

Production Hardening:

• ✅ Modular architecture (4 specialized damage modules)
• ✅ Zero magic numbers (all constants centralized)
• ✅ Defensive programming (safe_divide, capitalize_annual_cost)
• ✅ JSON Schema validation with auto-fix
• ✅ Comprehensive logging
• ✅ 100% backward compatible with Version 1.0.0

Calculation Methodology:

• USPAP 2024 compliant
• CUSPAP 2024 compliant
• Ontario Expropriations Act framework
• Before/after appraisal method

Validation & Quality Assurance

```bash

# Validate input before calculation

python validate_severance.py input.json

# Common issues auto-fixed:

# - Missing optional fields (adds defaults)

# - Boolean/number type conversions

# - Market parameter defaults

```

---

This skill activates when you:

• Calculate severance damages from partial property takings
• Quantify access impairment from loss of frontage, circuitous access, or landlocked conditions
• Value irregular remainder parcels using shape efficiency ratios or development yield analysis
• Assess loss of highest and best use from size or configuration constraints
• Calculate farm operation disruption from field division, equipment access, or irrigation impacts
• Apply cost-to-cure vs. value-loss methodologies for severance damages
• Reconcile severance damage calculations with before/after market value approach