In many cities, groundwater is essential for human consumption. However, urban aquifers coexist with the constant risk of contamination by the various types of pollutants from heterogeneity of activities. Nitrate is the main pollutant found in aquifers in terms of abundance, and may be able to promote much harmful to human health and the aquatic environment. In this context, this study goal to evaluate the nitrate contamination plume in part of the Metropolitan Region of Maceió City and looking for evidence of the effect of recharging on pollutant dynamics. To do this, we used the MODFLOW code to simulate the steady state distribution of hydraulic load, the MODPATH for tracking particles and MT3DMS to describe the transport and fate of nitrate. The results show that the seasonality of precipitation introduced no significant influence on the water level variations in deep sedimentary aquifer as well as the contaminant dispersion. Furthermore, there is a probability that disposal of sewage in long-term on soil govern the dynamics of the nitrate concentration in 87.5% of monitoring wells. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Em muitas cidades as águas subterrâneas são imprescindíveis para o abastecimento humano. Porém, os aquíferos urbanos convivem com o constante risco de contaminação em virtude dos diversos tipos de poluentes originados da heterogeneidade das atividades que acorrem na superfície do solo. Um dos principais poluentes encontrados em termos de abundância é o nitrato, e que pode ser capaz de promover diversos danos à saúde humana e ao ambiente aquático. Neste contexto, este trabalho teve por objetivo avaliar a pluma de contaminação do nitrato em parte da Região Metropolitana de Maceió e buscar por evidências do efeito da recarga na dinâmica do poluente. Para tal, foi utilizado o código MODFLOW para simular o estado de equilíbrio da distribuição da carga hidráulica, o MODPATH para o rastreamento de partículas e o MT3DMS para descrever o transporte e destino do nitrato. Os resultados evidenciam que a sazonalidade da precipitação não apresentou influência significativa nas variações do nível de água em aquífero sedimentar profundo assim como na dispersão do contaminante. Além disso, há probabilidade que a disposição de dejetos sanitários no solo em longo prazo governe a dinâmica da concentração de nitrato em 87,5% dos poços de monitoramento.

This project proposes a new urban aquifer strategy that utilizes stormwater to create a cascading plaza and an improved 'great street' in Washington DC. A system of urban aquifers is developed beneath the surface of the street, perched atop the compacted, impermeable soils below. This set of aquifers prevents stormwater from entering the existing combined sewer and allows trees to draw water from this new groundwater source and develop expansive root systems. On the surface, stormwater flows through interconnected planters where it irrigates and is filtered by vegetation before infiltrating to recharge the aquifer. At Cascade Plaza, sloping topography intersects the aquifer, and the new groundwater seeps out of the plaza steps, turning them into a miniature cascade, by gravity and water pressure alone. It collects in a web of runnels, pools at the lowest point, and overflows in high water, mysteriously disappearing below ground again to fill an underground reservoir. In this unique ecological system, water flows both above and below ground to mitigate excess stormwater and make the street and plaza more beautiful. / Master of Landscape Architecture / This project proposes a new urban aquifer strategy that utilizes stormwater to create a cascading plaza and an improved ‘great street’ in Washington DC. A system of urban aquifers is developed beneath the surface of the street, perched atop the compacted, impermeable soils below. This set of aquifers prevents stormwater from entering the existing combined sewer and allows trees to draw water from this new groundwater source and develop expansive root systems. On the surface, stormwater flows through interconnected planters where it irrigates and is filtered by vegetation before infiltrating to recharge the aquifer. At Cascade Plaza, sloping topography intersects the aquifer, and the new groundwater seeps out of the plaza steps, turning them into a miniature cascade, by gravity and water pressure alone. It collects in a web of runnels, pools at the lowest point, and overflows in high water, mysteriously disappearing below ground again to fill an underground reservoir. In this unique ecological system, water flows both above and below ground to mitigate excess stormwater and make the street and plaza more beautiful.