In the karst regions of Mexico, the construction of cities has been carried out using materials and processes that do not correspond to the functioning of filtration dynamics. The present work analyzes the effects of WSUD (Water Sensitive Urban Design) implementation on karst zone and the influence in the reduction of flooding. A permeability model was developed for the urban area of Bacalar, Quintana Roo, Mexico. As a first phase, precipitation, runoff, and infiltration were modeled; the useful infrastructure to maintain the connectivity of the hydrological system was determined and permeability models considering different scenarios were generated. In the second phase, the efficiency of the model scenarios was analyzed. Finally, flood damages were assessed for each scenario. The results show that if 68% of the urban area is kept permeable and 32% impermeable with sponge infrastructure, with a return period of 10 years, the onset of flooding is delayed by up to 30 minutes. This implies a saving of 5.56 million minimum wages. The implementation of DUSA reduces flooding, generates social and economic savings, but also maintains the flow dynamics and connectivity of the karst. The international DUSA model reduces the vulnerability of karst systems to climate change. | En las regiones kársticas de México la construcción de ciudades se ha realizado con el uso de materiales y procesos que no corresponden con el funcionamiento de la dinámica de filtración del agua. Con el uso de modelos hidrodinámicos se analizó la implementación del Diseño Urbano Sensible al Agua (DUSA) en el karst y se evaluó el beneficio económico al disminuir las inundaciones en Bacalar, Quintana Roo, México. Como primera etapa se modeló la precipitación, escorrentía e infiltración; se determinó la infraestructura útil para mantener la conectividad del sistema hidrológico y se generaron escenarios modelo de permeabilidad. En la segunda etapa se analizó la eficiencia de los escenarios modelo. Finalmente se valorizaron los daños de inundación para cada escenario. Los resultados muestran que, si se mantiene un 68% de área urbana permeable y 32% impermeable con infraestructuras esponja, con periodo de retorno de 10 años, se retrasa hasta por 30 minutos el inicio de las inundaciones. Esto implica un ahorro de 5.56 millones de salarios mínimos. La implementación de DUSA reduce inundaciones, genera ahorros sociales y económicos, pero además mantiene la dinámica de flujo y conectividad del karst. El modelo internacional de DUSA disminuye la vulnerabilidad de los sistemas kársticos ante el cambio climático.

D. Kaimowitz, 'Cuatro medio verdales: la relacion bosques y agua en Centroamericana', 2001 | This paper looks at four “half-truths” about the relations between forests and water in Central America. The first is that deforestation has reduced rainfall in certain regions of Central America. The second is that forest help to maintain dry season stream flow. The third is that deforestation has led to more intense flooding. The fourth is that the region’s hydroelectric reservoirs and the Panama Canal are rapidly becoming sedimented. As the name implies, the article argues that each of these has some elements of truth but other aspects that are myths. The author emphasizes that even though some of these claims are myths action still needs to be taken to avoid inappropriate deforestation and forest degradation

Climate change is at the top of the development agenda in Central America. This region, together with the Caribbean, is highly vulnerable to the effects of climate change in Latin America. Climate change is manifesting itself through higher average temperatures and more frequent droughts that result in higher water stress, and through the rising frequency of extreme weather events such as tropical storms, hurricanes, floods and landslides, all of which pose significant challenges in the rural water supply and sanitation sector. The paper starts with a review of the historic data on temperature and precipitation trends in Central America and particularly at the regional level in Nicaragua. The data reveal a clear trend of the growing climate variability, increased water stress for crops, and greater frequency of extreme weather events. The rising intensity and frequency of ex-treme weather events is among the most critical risks to the region's development agenda, and they translate into high economic losses. This paper examines the impacts and implications of potential climate change on water resources in Nicaragua and makes key recommendations to integrate climate change and rural water supply and sanitation policies and programs in a way that increase resilience to current and future climate conditions. | 0

Resumen: En las regiones kársticas de México la construcción de ciudades se ha realizado con el uso de materiales y procesos que no corresponden con el funcionamiento de la dinámica de filtración del agua. Con el uso de modelos hidrodinámicos se analizó la implementación del Diseño Urbano Sensible al Agua (DUSA) en el karst y se evaluó el beneficio económico al disminuir las inundaciones en Bacalar, Quintana Roo, México. Como primera etapa se modeló la precipitación, escorrentía e infiltración; se determinó la infraestructura útil para mantener la conectividad del sistema hidrológico y se generaron escenarios modelo de permeabilidad. En la segunda etapa se analizó la eficiencia de los escenarios modelo. Finalmente se valorizaron los daños de inundación para cada escenario. Los resultados muestran que, si se mantiene un 68% de área urbana permeable y 32% impermeable con infraestructuras esponja, con periodo de retorno de 10 años, se retrasa hasta por 30 minutos el inicio de las inundaciones. Esto implica un ahorro de 5.56 millones de salarios mínimos. La implementación de DUSA reduce inundaciones, genera ahorros sociales y económicos, pero además mantiene la dinámica de flujo y conectividad del karst. El modelo internacional de DUSA disminuye la vulnerabilidad de los sistemas kársticos ante el cambio climático. | Abstract: In the karst regions of Mexico, the construction of cities has been carried out using materials and processes that do not correspond to the functioning of filtration dynamics. The present work analyzes the effects of WSUD (Water Sensitive Urban Design) implementation on karst zone and the influence in the reduction of flooding. A permeability model was developed for the urban area of Bacalar, Quintana Roo, Mexico. As a first phase, precipitation, runoff, and infiltration were modeled; the useful infrastructure to maintain the connectivity of the hydrological system was determined and permeability models considering different scenarios were generated. In the second phase, the efficiency of the model scenarios was analyzed. Finally, flood damages were assessed for each scenario. The results show that if 68% of the urban area is kept permeable and 32% impermeable with sponge infrastructure, with a return period of 10 years, the onset of flooding is delayed by up to 30 minutes. This implies a saving of 5.56 million minimum wages. The implementation of DUSA reduces flooding, generates social and economic savings, but also maintains the flow dynamics and connectivity of the karst. The international DUSA model reduces the vulnerability of karst systems to climate change.