都市垂直性的風險治理：台北市污水下水道施工個案研究

The Risk Governance of Urban Verticality: Case Studies of Sewer Construction in Taipei

都市垂直性的營造充滿風險，而風險之分派和應對有其制度脈絡，並形成了風險治理。本文以兩個污水下水道工程為例，說明在政府採購招標法規及公共工程體制下，台北市衛生下水道工程處逐漸從規劃單位轉變為主責發包和監督，並廣納民力以回應提升都市基礎設施的迫切需求。另一方面，面臨污水下水道施作的地質和水文條件等地底不確定性，廠商在招標法規的框架下，除了負擔成本，也須仰賴自身的彈性網絡化能力來調動資源或變更原初設計與工法，以便處理意外和進度落後問題。於是，晚近都市治理及基礎設施興建的轉變，遠非新自由主義化一詞所能涵蓋，而必須考慮具體的制度脈絡、物質性及因應風險的技術。彈性網絡化不僅是廠商為回應政府招標要求及工程難題，進而提升專業能力的依據，也體現了廠商與政府之間在特定公共工程體制下，由基礎設施工程的都市垂直性及地底不確定性中介的風險攤派。

The construction of urban verticality is full of risks, and the allocation and response to risks have their own institutional context, which forms risk governance. This article takes two sewer construction projects as examples, and illustrates that under the government procurement bidding regulations and the public construction regime, the Sewerage Systems Office of Taipei City Government gradually changed from a planning unit to a unit responsible for contracting, supervising, and recruiting non-governmental companies’resources to respond to the urgent need to upgrade urban infrastructure. Furthermore, in the face of underground uncertainties such as geological and hydrological conditions for sewer construction, builders must not only bear the costs under the framework of bidding regulations, but also rely on their elastic networking ability to mobilize resources or change the original design and construction method, so as to prevent engineering accidents and schedules lagging behind. Therefore, the recent changes in urban governance and infrastructure construction are far from being covered by theories on neo-liberalization. Additionally, the specific institutional context, materiality, and technology in response to risk must be considered. Elastic networking is not only the basis for builders to improve their professional capabilities in response to government bidding requirements and engineering problems, but also reflects the allocation of risk between builders and the government under a specific public construction regime, which is mediated by urban verticality and underground uncertainties of infrastructure projects.