Abstract

Problem, research strategy, and findings

Why would plans have an impact on the built environment when their provisions can be revisited in the context of individual development decisions? I examined the causal impacts of transit-oriented development (TOD) plans in San Francisco (CA) and Seattle (WA) using a mixed methods approach, combining qualitative interviews and a quantitative regression discontinuity design. I found that the Market and Octavia Plan in San Francisco had a substantial impact on development outcomes, increasing densities and reducing parking ratios not just within the plan boundaries but also in adjacent neighborhoods. In Seattle, although parking ratios declined and densities rose over time, it is harder to attribute these trends to the TOD plans studied here, which constituted a small part of the city’s overall planning program. Beyond zoning changes, I identified two mechanisms through which plans exert an impact. First, in a city where development approvals are not by-right, plans can act as an anchor point for bargaining among developers, city staff, and community members. Second, plans can serve as laboratories of innovation, enabling experimentation with new policies that can later be extended to adjacent communities. These findings, however, may not extend to places where zoning provides by-right development permission or where community members are implacably opposed to new development.

Takeaway for practice

Planners should consider the mechanisms through which plans exert causal impacts. In particular, they should strive for plans that provide a lasting compromise and leave limited incentives for stakeholders to reopen controversial debates in the context of individual project approvals. Planners can also use TOD and similar plans as sites of experimentation and innovation.

中文翻译：

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计划即讨价还价

摘要

问题、研究策略和发现

当他们的规定可以在个人开发决策的背景下重新审视时，为什么计划会对建筑环境产生影响？我使用混合方法，结合定性访谈和定量回归不连续性设计，研究了旧金山 (CA) 和西雅图 (WA) 以公交为导向的开发 (TOD) 计划的因果影响。我发现旧金山的 Market 和 Octavia 计划对发展成果产生了重大影响，不仅在计划边界内，而且在邻近社区增加了密度并降低了停车率。在西雅图，虽然停车率随着时间的推移而下降，密度在上升，但很难将这些趋势归因于这里研究的 TOD 计划，它构成了城市整体规划计划的一小部分。除了分区变化，我确定了计划产生影响的两种机制。首先，在一个开发审批不合理的城市，规划可以作为开发商、城市工作人员和社区成员之间讨价还价的锚点。其次，计划可以作为创新实验室，使新政策的试验能够在以后扩展到邻近社区。然而，这些发现可能不会扩展到分区提供了权利开发许可或社区成员无情地反对新开发的地方。能够试验新政策，这些政策以后可以扩展到邻近社区。然而，这些发现可能不会扩展到分区提供了权利开发许可或社区成员无情地反对新开发的地方。能够试验新政策，这些政策以后可以扩展到邻近社区。然而，这些发现可能不会扩展到分区提供了权利开发许可或社区成员无情地反对新开发的地方。

外卖练习

规划者应考虑计划产生因果影响的机制。特别是，他们应该努力制定能够提供持久妥协的计划，并为利益相关者在个别项目批准的背景下重新开始有争议的辩论留下有限的激励。规划者还可以使用 TOD 和类似的计划作为实验和创新的场所。