The Sebago Lake watershed covers an area of about 440 square miles and extends from Bethel to Standish, Maine. In the map, the location of stream gauging sites is shown. Many of these locations where previously used to monitor streamflow by the USGS (Citation), and in some cases, we are re-using staff gauges set and abandoned by the USGS. Measurements at monitoring sites began in 2010 and continue through 2014. Streamflow data has been collected with a Marsh-McBirney style electromagnetic flow meter. Limited data has been collected during high flows in streams, in part due to safety reasons. As a result, the relationship between high discharge and high stage values is poorly constrained.
Data from three streams are shown in the adjacent plots (top: Thomas Pond outlet, middle: Northwest River, and bottom: Crooked River) Each plot contains three panels: The bottom panel contains water level data collected at 20 minute intervals with a data logging pressure transducer, the small inset plots flow rates (discharge) measured during site visits against stream water level with a line fit through the date points, and the upper graph presents calculated stream discharge based on the relationships in the other two graphs. The yellow shading on the discharge plots indicate the range where data is well constrained by measurements. Data outside of this interval should be viewed with some skepticism.