Because much of the volume may be contributed to recharge of ground water supplies. Draining these wetlands eliminates their recharge capacity and may adversely affect the surrounding soil moisture during dry periods. The water in this wetland is relatively permanent. Draining wetlands with ground water discharge capacity actually increases ground water discharge initially. However, over an extended period local water tables may be lowered.
Wetlands located lower than the water table can receive ground water discharge.
Seasonal rainfall patterns may influence the direction of ground water flow within a wetland. During the spring, when water inputs are high, the wetland water level may be higher than the water table. At this time, the wetland acts as a point of recharge as water seeps from the wetland into the ground water. As the summer progresses, wetland water levels might drop to a level below the water table. In many instances the same wetland may serve both functions.