Various Traffic Impact Analysis (TIS) methods have been developed to evaluate the impact of land development on transportation system performance. Traditional TIS approaches are often limited to static traffic performance models or lack strong travel behavior foundation. This study integrates dynamic traffic assignment (DTA) with agent-based travel behavior models (routing, departure time shifts, etc.) for land development impact studies. The integrated model enhances the behavior realism of DTA as well as captures the traffic dynamics. It provides an advanced yet practical approach to understanding the impact of a single or a series of land development projects on route choice, peak spreading, modal shifts, dynamic traffic conditions, intersection and regional transportation system performance. To demonstrate this proposed approach, a case study that focuses on cumulative land development impact along an already congested corridor in Maryland, the I-270/MD-355 corridor, is conducted.