--- name: severance-damages-quantification-reggiechan74 title: Basic calculation description: Use when valuing the remainder after a partial taking — quantifying frontage loss by road class ($/linear foot), circuitous-access capitalization, landlocked-parcel easement cost-to-cure, shape-efficiency-driven development yield loss, or farm operation disruption (fencing, equipment crossings, irrigation severance). Before/after method with cost-to-cure vs. value-loss reconciliation. author: reggiechan74 author_url: https://github.com/reggiechan74/vp-real-estate/tree/main/plugins/expropriation-law/skills/severance-damages-quantification license: Apache-2.0 version: 0.1.0 execution_mode: open jurisdiction: ca practice: real-estate language: en --- **Scope boundary**: This skill covers *structural/configurational* loss to the remainder after a partial taking (frontage, shape, access, utilities, farm severance). For *external* impacts from the works (noise, dust, vibration, proximity, business loss during construction), use `injurious-affection-assessment`. Both fall under OEA s.18. ## Access Impairment Analysis Quantifying reduced access value from loss of frontage, circuitous access, or landlocked conditions. ### Direct Frontage Loss ($/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 2. **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 3. **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) ## Shape Irregularity 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** ## Utility Impairment 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** ## Farm Operation Disruption 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) --- ## Calculator Usage 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 ```