Rivers are key passageways connecting inland waters to the world’s oceans. They are responsible for the mobilization and transport of nutrients, sediments, and weathered materials. Rivers have been influential in the development of human civilization and are hubs for people and businesses to populate. As our population puts a heavier burden on these waterways, there is a need to better understand the controls on their water quality.
The overarching goal of this research is to improve our understanding of the hydrology and water resources of the Upper Hudson and Mohawk watersheds. This is critical to our understanding of the ecological and environmental roles these watersheds play while ensuring ample clean water. To address these issues, we studied six rivers in the Upper Hudson and Mohawk watersheds, looking at how lithology, land use, and physical hydrology impact the geochemistry and water quality of the rivers.
I performed an analysis of the physical hydrology of the rivers with a focus on streamflow patterns and long term trends in flow characteristics. This includes looking at shifts in flow timing, duration and magnitude of low flows, and shifts in annual mean flows. Our results help to paint the picture of how climatic changes are linked with the streamflow values and how they are changing now. I also developed concentration discharge curves to couple with the hydrograph analysis to look at how elemental fluxes vary with changes in streamflow.
In addition to the hydrograph analysis, we performed in depth characterizations of water quality and geochemical conditions in the rivers. We sampled under both low flow and high flow conditions on all of the streams. Our results revealed a strong geologic control on stream chemistry however, we observe that some chemical parameters are highly influenced by anthropogenic activities. Notably, we see that our measurements of Na and Cl are higher than historic measurements by the USGS taken on these same streams. Given that other constituents such as Ca, Mg, and K have remained at typical historic levels, we believe that the elevated levels of Na and Cl are do to anthropogenic impacts of road salting. Of particular concern, all of the streams have elevated levels of Na and Cl under baseflow conditions when the stream is fed by groundwater discharge. Thus our results show that groundwater resources have been impacted by road salting which will continue to pollute the streams and will take decades to flush.