Plan–Operations Gap Analysis for Urban Drainage Risk: Comparing 2026 Service-Order Hotspots with a 2011 Macrodrainage Plan in Guarujá, Brazil

Introduction: Urban flooding risk management depends on aligning long-term drainage planning with day-to-day operational evidence of stormwater system stress. Guarujá (São Paulo, Brazil) has a macrodrainage master plan produced in 2011, while municipal maintenance records continue to register recurrent unclogging interventions across the city. This study proposes a plan–operations comparison framework to assess whether locations showing high recurrence of drainage-related work orders in 2026 are covered by critical points and intervention proposals in the 2011 macrodrainage plan, and to identify recurrent hotspots absent from the plan that may signal post-plan changes in failure patterns.

Methods: We compiled and standardized municipal drainage unclogging work orders (January 2020–February 2026) and built a street-level hotspot ranking. In parallel, we extracted from the 2011 plan its catalog of critical areas, basin references, diagnostics, and proposed structural measures. Hotspots were matched to plan elements using a concordance matrix and classified into four practical categories: (A) planned-but-still-critical; (B) aligned with plan diagnostics but lacking a clear intervention pathway; (C) recurrent hotspots absent from the plan (candidate emerging hotspots); and (D) plan-identified critical points with low current recurrence.

Results: Preliminary results indicate both (i) persistent operational recurrence in areas already highlighted in the plan, suggesting implementation gaps, insufficient mitigation, or maintenance-sensitive mechanisms, and (ii) a set of recurrent hotspots not referenced in the plan, which may warrant targeted field diagnostics and risk-based prioritization.

Conclusions: The framework provides a transparent way to translate operational recurrence into actionable management questions, supporting decisions to execute pending interventions, refine maintenance strategies, and prioritize on-site investigation where planning coverage is missing.