CONNECTION BETWEEN VERNAL POOLS AND GROUND WATER, PAWCATUCK WATERSHED, SOUTHERN RHODE ISLAND

In 2002 a hydroperiod of 2 weeks was observed at Martin Pond, a vernal pool in the Pawcatuck Watershed in southern Rhode Island. This was significantly shorter than the estimated hydroperiod of 23.5 weeks as determined by a large 65 pond study by Skidds et al, 2003. In the same year the nearby South Kingstown Land Trust (SKLT) vernal pool had a hydroperiod of only 5 weeks, compared to the hydroperiod of 27.6 weeks estimated by Skidds, 2003.

Both Martin Pond and SKLT are located in the contributing area of the municipal well field off of Tuckertown Road in South Kingstown. Martin Pond is less than ¼ of a mile north of the municipal well field and SKLT is just over 1 mile southwest of the municipal well field. Pumping from the Tuckertown Road municipal well field may have an influence on the hydroperiod of these vernal pools.

The two vernal pools near the Tuckertown well field, Martin Pond and SKLT, in addition to another vernal pool with similar geology were selected as test sites. Three separate techniques to determine the presence of a connection between the vernal pool and the ground water are being used. These methods include ground water and surface water level monitoring, analysis of surface water and ground water temperature using Dallas semiconductor's ibuttons, and analysis of isotopic signatures of water within the vernal pools.