Tropical mid-size cities on alluvial floodplains face compounded flood challenges combining pluvial accumulation from intense convective storms, regulated river overflow, and aging drainage networks. This study presents an integrated framework for Monteria, Colombia (~450,000 inhabitants; Sinu River, Caribbean lowlands), within Colombian Decree 1807/2014 and structured in four phases. (1) Hazard: A Rain-on-Grid 2D HEC-RAS 6.6 model covering 4090 ha, calibrated against four gauged events, identifies three dominant pluvial mechanisms (poor hydraulic connectivity, limited evacuation capacity, downstream channel overflow), plus 17 critical fluvial erosion points affecting ~289 properties at 100-year return period. (2) Vulnerability: Depth-damage functions from 1465 household surveys yield 36.36% of 3015 assets in high risk and 57.77% in medium risk. (3) Measures: Scenario M2 (channel widening plus dikes, land-raising, retention lagoons) removes 80 ha of flooding while displacing 28 ha at COP 845 million pre-design cost. Non-structural measures include a Sustainable Urban Drainage Master Plan, IoT-based Early Warning System, minimum construction-elevation map, and land-management instruments. A Monte Carlo residual-risk model reduces baseline risk to 19.9% under full implementation. (4) Emergency: A February 2026 cold-front event was addressed with a 4300 m perimeter dike and six pump stations deployed jointly by the Regional Environmental Authority (CVS) and Municipal Administration.

The objective of this study was to identify the main causes of inadequate solid waste management in Mocoa, Putumayo, and to propose viable circular economy (CE) solutions. To achieve this, an analysis of local planning instruments was carried out, including the Integrated Solid Waste Management Plan (PGIRS) and the Basic Land Use Plan (PBOT). In addition, a technical round table with key stakeholders was held using the problem tree methodology to identify the causes and effects of inefficient waste management. The Analytical Hierarchy Process (AHP) method was then used to prioritize the 15 most relevant causes, complemented by the Borda method, to obtain a final ranking. The results show that social stigmatization of recyclers (Borda score of 96), consumer culture (92) and lack of waste management strategies (92) are critical factors, accounting for 52.71% of the total impact on the problem. It is concluded that the inclusion and formalization of recyclers in the waste management system, through policies such as Decree 596 of 2016, is essential to improve the sustainability of the system. The need for environmental education programs that promote community participation and reduce excessive consumption is also highlighted. The novelty of this study lies in the combination of the AHP method and Borda method to prioritize causes, which makes it possible to focus limited resources on solutions with the greatest impact. This methodology provides a systematic approach to addressing waste management challenges and promoting a transition to a circular economy, thus contributing to the achievement of Sustainable Development Goals (SDGs) in emerging cities such as Mocoa.

Tropical mid-size cities on alluvial floodplains face compounded flood challenges com-bining pluvial accumulation from intense convective storms, regulated river overflow, and aging drainage networks. This study presents an integrated framework for Mon-teria, Colombia (~450,000 inhabitants; Sinu River, Caribbean lowlands), within Colom-bian Decree 1807/2014 and structured in four phases. (1) Hazard: a Rain-on-Grid 2D HEC-RAS 6.6 model covering 4,090 ha, calibrated against four gauged events, identifies three dominant pluvial mechanisms (poor hydraulic connectivity, limited evacuation capacity, downstream channel overflow), plus 17 critical fluvial erosion points affecting ~289 properties at 100-year return period. (2) Vulnerability: depth-damage functions from 1,465 household surveys yield 36.36% of 3,015 assets in high risk, 57.77% in medium risk. (3) Measures: scenario M2 (channel widening plus dikes, land-raising, retention lagoons) removes 80 ha of flooding while displacing 28 ha at COP 845 million pre-design cost. Non-structural measures include a Sustainable Urban Drainage Master Plan, IoT-based Early Warning System, minimum construction-elevation map, and land-management instruments. A Monte Carlo residual-risk model reduces baseline risk to 19.9% under full implementation. (4) Emergency: a February 2026 cold-front event was addressed with a 4,300 m perimeter dike and six pump stations deployed jointly by the Regional Environmental Authority (CVS) and Municipal Administration.

En el mundo, miles de personas habitan, desarrollan sus labores y dependen económicamente de entornos acuáticos, como los humedales, ríos, caños, océanos, deltas y llanuras propensas a inundaciones. La interacción constante entre el agua, el suelo y las comunidades ha generado nuevas perspectivas teóricas y etnográficas para comprender la vida humana en estos entornos húmedos (Gutiérrez Campo y Escobar Jiménez, 2021). Según Fals (1979), esta dinámica está regulada por costumbres, creencias y prácticas relacionadas con el cuidado del entorno natural, el uso de las tecnologías y las normas de producción. Estos territorios, denominados anfibios por su coexistencia dinámica entre ambientes terrestres y acuáticos, enfrentan desafíos socioecológicos complejos (Restrepo-Marín et al., 2022). Este tipo de desafíos afecta el desarrollo de las comunidades, causando consecuencias sociales, económicas y ambientales, por lo que es objeto de investigación y conlleva su posterior análisis.

As a result of this research, it is proposed the incorporation of risk management as an environmental determinant in flood areas of the lower Sinú River basin for territorial planning. This was carried out through the analysis of the total flood risk, determining the threat and vulnerability of the target community, likewise, the risk drivers were identified under approaches of the integral analysis of holistic and systemic risk using a PAR model through which it is established the underlying reason, the dynamic relationship of the environment, the unsafe conditions of geography, and the socio-economic characterization of the community. In this way, it was not only obtained the analysis of the areas affected by the floods by identifying the causes and establishing a level of risk tolerance, but also the risk factors with their effects in the study area. This highlighted the importance of developing immediate and priority activities in the study area