Vernal pools are shallow, seasonal wetlands, underlined by an impermeable or slowly permeating layer, that form in depression pools. Vernal pools in California have been decimated by land developments. This has caused increased habitat fragmentation for vernal pool species. A thorough understanding of the vernal pools hydrology is imperative to their continued survival, as they are important refugia for endangered, endemic vernal pool species. The purpose of my research is to study the hydrological connectivity of two three–vernal pool series. My results show that vernal pools are hydrologically connected to each other and to the landscape. There are several variables that determine its degree of hydrological connectivity– shallow subsurface confining layer, perched groundwater and surface water flow, inundation, and location. Understanding the hydrology of this unique environment is imperative to the success of vernal pools and its species, as they undergo habitat loss and stresses associated with climate change.