The focus of the study was to figure out how to accurately measure water scarcity by considering how reservoirs manage water. Scientists developed a simulation model for the Haihe River in China to show the impact of reservoirs on water availability. When they included reservoir regulation in their evaluation, they found that water scarcity was not as bad as previously thought. Without accounting for reservoirs, the water stress level seemed higher, but including them in the assessment revealed less severe water scarcity. This research suggests that reservoirs play a crucial role in managing water scarcity, especially in smaller regions. To better manage water resources, it is important to factor in how reservoirs affect water availability.