Objective As water-networked cities shift toward the regeneration of existing urban areas, blue−gray infrastructure is increasingly being reconsidered not only as an engineering system, but also as a public spatial resource. Traditionally, canals, roads, drainage, flood-control structures, and municipal corridors have been planned mainly for efficiency, safety, and operation. However, with growing demands for urban quality, public life, cultural production, and creative economy, these infrastructural spaces are expected to accommodate broader social and spatial values. In practice, many blue−gray infrastructural spaces remain enclosed, fragmented, poorly accessible, and weakly connected with surrounding urban activities. This limits their capacity to support public interaction, cultural expression, creative production, ecological experience, and everyday vitality, creating a mismatch between blue−gray infrastructure and urban creative fields, which depend on openness, communication, spatial experience, and cross-boundary interaction. To address this issue, this study examines how blue−gray infrastructure and creative fields can shift from unidirectional support to reciprocal synergy. Using central Suzhou as the empirical case, it aims to provide theoretical and strategic references for creative urban regeneration in water-networked regions, coordinating the industry−water−city nexus and modernizing water-network systems.

Methods This study investigates the spatial relationship between blue−gray infrastructure and urban creative fields. First, POI data of creative enterprises are used to identify creative activity distribution. The HDBSCAN (Hierarchical Density-Based Spatial Clustering of Applications with Noise) algorithm is then applied to delineate the empirical boundaries of creative hubs, avoiding analyses based solely on administrative boundaries and improving identification of creative agglomeration patterns. On this basis, a bivariate spatial association evaluation model is constructed to examine the coupling relationship between creative enterprise clusters and blue−gray infrastructure. By integrating indicators of public accessibility, visual accessibility, and kernel density of creative enterprises, the model evaluates alignment between infrastructure service supply and the spatial demands generated by creative activities. This analysis clarifies not only where creative resources are concentrated, but also whether nearby infrastructural spaces can support public interaction, creative spillover, spatial experience, and urban vitality. To further reveal the mechanisms behind the observed patterns, quantitative spatial analysis is combined with fine-grained spatial diagnosis. Through micro-interface typological analysis, case studies, and space syntax analysis, the study identifies the key constraints that restrict interaction between infrastructure and creative activities. Particular attention is paid to the interfaces between infrastructure and surrounding urban blocks, including accessibility, boundary permeability, functional mix, visual continuity, pedestrian experience, and publicness. Based on these analyses, regeneration strategies oriented toward spatial synergy are proposed.

Results The results show that the relationship between blue−gray infrastructure and creative fields in central Suzhou is characterized by spatial proximity but weak functional association. Creative enterprises and cultural activities tend to cluster near canals, streets, waterfront corridors, and other infrastructural spaces. Nevertheless, geographical adjacency does not automatically generate effective spatial interaction. In many areas, the level of synergy remains limited, and infrastructure supply and creative spatial demand are poorly aligned. Two typical forms of mismatch are identified. The first appears in areas where creative demand is strong, but public infrastructural spaces fail to provide sufficient support for communication, interaction, and experience. The second appears in areas where infrastructural assets are present, but the cultural, spatial, and operational conditions required for activation are insufficient. At the micro scale, impermeable interfaces and limited functional diversity are the main constraints. Walled boundaries, interrupted pedestrian connections, poor accessibility, and single-use spaces reduce the ability of blue−gray infrastructure to support public interaction, creative spillover, and urban vitality. These problems are especially evident in waterfront edges, bridgehead spaces, linear corridors, and leftover infrastructural plots where spatial resources exist but are not effectively transformed into public or creative places. These findings reveal the limitations of conventional engineering-oriented planning and management models, under which infrastructure is still treated largely as a passive technical facility rather than as an active public spatial asset involved in creative urban regeneration.

Conclusion In response to these findings, this study proposes a synergy-oriented regeneration framework with two interrelated dimensions. The first is the public-oriented transformation of blue−gray infrastructure, including node-based functional integration, human-scale reconnection of linear infrastructural corridors, soft-edged interface renewal, and the enhancement of regional spatial legibility. These strategies seek to transform enclosed, marginal, or purely functional infrastructural spaces into open, continuous, accessible, and experience-oriented public spaces. The second is the active embedding of creative activities and industries, including design-led intervention, operation-based activation, and industry-supported reinvestment. By introducing cultural activities, creative industries, public programs, and adaptive spatial design, urban creative fields can become active agents in infrastructure regeneration rather than merely external users. The study further develops a culture−power−economy coupling framework. Cultural mechanisms enhance the symbolic value and social identity of blue−gray infrastructure; power mechanisms provide institutional support for spatial coordination, cross-sector collaboration, resource allocation, and public participation; and economic mechanisms strengthen the operational capacity and industrial sustainability of creative activities. This framework emphasizes that spatial renewal should not rely only on physical design, but should also involve institutional coordination, continuous operation, and the cultivation of creative production networks. Overall, the study demonstrates the feasibility of transforming passive blue−gray infrastructure into an active spatial medium that interacts with creative resources, thereby promoting a more coordinated relationship between infrastructure renewal and creative urban regeneration in water-networked urban regions.