The major ion chemistry of precipitation and four undisturbed streams was measured in the New Jersey Pinelands (Pine Barrens) in 1970-1972 and 1984-1988. Over the interval, the sea salt corrected concentration of Ca and SO4 significantly declined in precipitation and all streams. Analytical problems prevented analysis of the change in precipitaion H, but H significantly declined in all streams. The change in precipitation and stream water Mg and K was less consistent but was generally toward lower concentrations 1984-1988. After examing the potential contribution of analytical artifacts and changes in watershed characteristics and hydrology to these results, it was concluded that the changes in precipitation chemistry was real and resulted in direct changes in tream chemistry between 1970-1972 and 1984-1988. The direct effect of precipitation on stream water chemistry in the New Jersey Pinelands suggests that this region is an ideal locality to investigate future long-term linkages between precipitaion and surface water.