RUNOFF GENERATION OF JAY-5 AND THE EAST AUSABLE IN THE UPPER PEAKS OF THE ADIRONDACKS (NEW YORK)

As part of an NSF funded project to study 22 watersheds in the Adirondack Mountains (New York) we are studying a nested watershed with six subcatchments in the Rocky Branch drainage basin near Jay, New York. Our study of the Rocky Branch watershed focuses on the effects of watershed morphology, land use, bedrock types and surficial geology on base flow generation in streams. The watersheds range in basin area between 2.1 and 19.6 km˛. To better understand the effects of scale we are comparing runoff generation in the Rock Branch watersheds with the base flow generation in the basin of the East Branch of the Ausable River (508km˛), the larger river to which Rocky Branch flows. Discharge data for the East Branch of the Ausable River is monitored by the USGS. There are two main tributaries to Rock Branch. One tributary originates from a protected watershed (has not been logged in the last 50 years). The second tributary originates from a watershed that has been recently logged. The bedrock in each of the subcatchments is comprised metanorthosite and anorthosite gneiss. Surficial geology is dominated by bedrock outcrop, sand deltas and glacial till. Each watershed was instrumented with a continuously logging datalogger housed in stilling well to monitor river stage, water and air temperature. Discharge-stage rating curves were generated for each datalogger location to calculate discharge from stage data. Watershed characteristics for each watershed and the East Branch of the Ausable River were determined using GIS data layers of bedrock geology, surficial geology, topography and soil depth. We will present results from this study showing how watershed characteristic and scale affect per unit area base flow generation. We will determine where most of the base flow is generated in watershed.