Aquatic ecosystems are essential for the development of all forms of life. Water is the most valuable natural resource. The impact caused by contamination, urbanism, and population growth in the water bodies affects the ecosystems sustainability, raising the contamination levels in the water coast systems, and affecting the biodiversity of the ecosystems. One of the most important water bodies in Cartagena-Colombia is Juan Angola Creek. This study presents the sustainability assessment of water ecosystems based on the modified Water Poverty Index (WPI) to determine access, impact of anthropogenic activities, availability, and related parameters of bird biodiversity in the creek. The information to assess the index was taken from government reports for the components: resource, access, use, and capacity. Physicochemical, environmental, and bird parameters were taken in two samples distributed in a transect from the mouth of the creek to Torices’ bridge in the rainy and dry seasons of 2021 (m1), and 2022 (m2), respectively. The results indicated that water poverty was low in WPI and modified Water Poverty Index (WPI-mB), which indicates favourable environmental conditions for access to water sources and sustainable development measures. The bird parameters implementation marked a difference in the WPI-mB values because this involves the species that inhabit the water body affected by environmental changes. For future research, it is recommended to monitor other taxonomic groups in the biodiversity index to expand the information on ecosystem overexposure.