the level of the water table varies depending on the time of year but as this is a very slow process it can take months for the rain to filter through to rivers.in fact ,depending on the route through the rock,some water can take hundreds of years before reappearing on the surface.the shape of the water table follows the shape of the surface and flows where the talde is high to where it is low.where the groundwater meets the surface,water leaves the rock,either as a spring or by seeping directly into rivers.dense evergreen forests are particularly effective at feeding groundwater supplies as they hold enormous amounts of rainfall allowing time for the water to slowly pass through the soil into the rock below.