Revisiting Hydrological Design Standards Under a Nonstationary Climate

Water resources infrastructure, dams, levees, drainage systems, and flood control structures, has traditionally been engineered against design standards derived from the assumption that hydrologic extremes are statistically stationary over time. Mounting evidence of shifting precipitation regimes, intensifying extreme events, and changing runoff patterns under anthropogenic climate change is eroding the validity of this assumption. Infrastructure designed decades ago under stationary assumptions is increasingly exposed to failure risk it was never intended to withstand, while new infrastructure risks being under- or over-designed if outdated standards persist. Authorities and engineers are under growing pressure to move from stationary to nonstationary design frameworks, but regional evidence, validated methods, and infrastructure risk assessments remain fragmented across the literature.The main goal of this Research Topic is to advance regional, evidence-based approaches to hydrological design that reflect a nonstationary climate, rather than the stationary assumptions embedded in most current infrastructure standards. Specifically, the Research Topic aims to: (1) develop regional nonstationary design approaches for water resources infrastructure; (2) identify and characterize hydrologic responses to nonstationary climate across regions; and (3) assess the failure risk of aging infrastructure in a changing climate, supported by case studies. Recent advances in nonstationary extreme value theory, time-varying return period estimation, and machine learning-based hydrologic forecasting offer new tools to address this problem, but their application to real infrastructure design and risk assessment remains limited. By bringing together regional case evidence and methodological advances, this Research Topic aims to support a shift toward design standards and infrastructure planning frameworks that are robust under a nonstationary climate.This Research Topic invites contributions that advance the science and practice of nonstationary hydrological design. We welcome studies that:- Develop and test regional nonstationary design approaches for water resources infrastructure- Characterize hydrologic responses (floods, droughts, rainfall intensity-duration-frequency relationships) to a changing climate across different regions and climatic zones- Assess the failure risk of aging infrastructure under evolving hydroclimatic conditions, including case studies- Apply methodological advances such as nonstationary extreme value analysis, time-varying return period frameworks, and machine learning-based hydrologic forecasting- Explore applied and policy-relevant implications of nonstationary designWe welcome Original Research, Review, Mini Review, Perspective, Methods, and Case Report articles. Topic editors: Munir Ahmad Nayak, Kuk-Hyun Ahn, Mehvish Hameed Source: https://www.frontiersin.org/research-topics/86410/revisiting-hydrological-design-standards-under-a-nonstationary-climate