/tod-design

name: tod-design
description: >-
  Design transit-oriented developments using ITDP TOD Standard, global best
  practices, and density-distance gradient principles. Use when the user asks
  to design around a transit station, create a TOD plan, optimize development
  near transit, plan a transit district, design a station area, or develop
  around a metro stop, BRT station, tram stop, or rail station. Also use when
  discussing walk catchments around transit, density gradients from stations,
  or first-last mile connectivity.

Transit-Oriented Development (TOD) Design Skill

This skill provides a complete framework for designing transit-oriented developments based on the ITDP TOD Standard v3.0, global best practices from cities like Tokyo, Hong Kong, Copenhagen, Curitiba, and Singapore, and density-distance gradient principles derived from decades of empirical research. It covers the full workflow from transit mode classification through station area planning, density calibration, use mix programming, parking management, and first-last mile connectivity design.

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1. TOD Typology Selector

Use the following matrix to determine the baseline design parameters for any TOD project. Start by identifying the transit mode, then adjust using the context modifiers below the table.

Primary Classification by Transit Mode

| Transit Mode | Walk Catchment | Min Density | Typical FAR | Height Range | Character | |---|---|---|---|---|---| | **Metro / Heavy Rail** | 800m | 100 DU/ha | 3.0 - 10.0 | 6 - 40+ stories | Urban center, regional destination, highest intensity mixed-use | | **Light Rail / Tram** | 600m | 60 DU/ha | 2.0 - 5.0 | 4 - 12 stories | Urban neighborhood, linear corridor with medium-intensity nodes | | **BRT (Bus Rapid Transit)** | 500m | 50 DU/ha | 1.5 - 4.0 | 3 - 8 stories | Boulevard district, corridor-based development | | **Bus (frequent, <10 min headway)** | 400m | 30 DU/ha | 1.0 - 2.5 | 2 - 5 stories | Neighborhood center, incremental densification | | **Commuter Rail** | 800m | 40 DU/ha | 1.5 - 4.0 | 3 - 8 stories | Town center, park-and-ride transition to walkable core | | **Ferry Terminal** | 400m | 50 DU/ha | 2.0 - 5.0 | 3 - 8 stories | Waterfront district, tourism + residential + commercial |

Context Modifiers

Apply these after selecting the primary transit mode to fine-tune parameters:

| Context | Density Modifier | FAR Modifier | Notes | |---|---|---|---| | **CBD / Central City** | +50% | +2.0 to +5.0 | Highest intensity justified by regional accessibility | | **Interchange Station (2+ lines)** | +30% | +1.5 to +3.0 | Multi-modal hub attracts higher ridership and demand | | **Terminus / End-of-Line** | -20% | -0.5 to -1.0 | Lower accessibility; park-and-ride may be appropriate | | **Suburban / Greenfield** | -30% | -0.5 to -1.5 | Lower existing demand; phase density over time | | **Historic / Heritage Area** | -20% | -1.0 to -2.0 | Height and massing constraints; character preservation | | **University / Hospital Anchor** | +20% | +0.5 to +1.5 | Institutional trip generators increase demand | | **Waterfront / Park Edge** | No change | No change | Adjust massing for view corridors and public access |

Walk Catchment Adjustments

The standard walk catchments above assume flat terrain and a connected street grid. Adjust as follows:

• **Hilly terrain (>5% average slope)**: reduce catchment by 20%
• **Poor street connectivity (cul-de-sac pattern)**: reduce catchment by 25%
• **Barriers (highway, river without crossing, rail line)**: truncate catchment at barrier
• **Excellent pedestrian environment (wide sidewalks, shade, weather protection)**: increase catchment by 15%
• **Covered or air-conditioned connections (Hong Kong, Singapore model)**: increase catchment by 25%

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2. ITDP TOD Standard -- 8 Principles

The Institute for Transportation and Development Policy (ITDP) TOD Standard v3.0 provides an internationally recognized framework for evaluating and designing transit-oriented developments. The standard scores developments on a 0-100 scale across 8 principles. Use these principles as both a design checklist and a scoring rubric.

Scoring Thresholds

| Award Level | Minimum Score | Interpretation | |---|---|---| | **Gold TOD Standard** | 85 or above | World-class TOD; exemplary in all dimensions | | **Silver TOD Standard** | 70 - 84 | High-quality TOD; strong performance with minor gaps | | **Bronze TOD Standard** | 55 - 69 | Good TOD; meets core criteria but has improvement areas | | Below Bronze | Below 55 | Does not qualify as TOD; significant redesign needed |

Principle 1: WALK (0-15 points)

**Goal**: Create a safe, complete, and comfortable pedestrian environment that makes walking the most attractive mode for short trips.

**Scoring Criteria**:

• Pedestrian network is complete with no gaps or dead ends (0-3 pts)
• Block perimeters are less than 250m for at least 90% of blocks (0-3 pts)
• Pedestrian crossings are safe, frequent, and accessible at every intersection (0-3 pts)
• Sidewalks are wide (minimum 2.0m clear), well-maintained, and ADA/universal-access compliant (0-3 pts)
• Pedestrian environment is comfortable: shade, weather protection, lighting, active frontages (0-3 pts)

**Design Implications**:

• Maximum block size: 120m x 120m (perimeter 480m), ideal 80m x 80m (perimeter 320m)
• Mid-block pedestrian passages for blocks exceeding 150m in any dimension
• Continuous sidewalks on both sides of every street, minimum 2.0m clear width
• Pedestrian crossings at all intersections, maximum 80m spacing on arterials
• Ground-floor transparency: minimum 60% glazing on commercial frontages
• Street trees for shade at 8-10m spacing, continuous canopy coverage target 40%+
• Pedestrian-scale lighting (4-6m poles, 3000K warm white, minimum 10 lux)

Principle 2: CYCLE (0-5 points)

**Goal**: Provide safe, connected cycling infrastructure and end-of-trip facilities that make cycling viable for trips up to 5 km.

**Scoring Cri