NOAA Hydrological Predictions for the Merrimack Basin
The National Oceanic & Atmospheric Administration (NOAA) Advanced Hydrological Prediction Service focused on the Merrimack Basin displays a graph of the Merrimack River's water table level.
The link address is: http://newweb.erh.noaa.gov/ahps2/hydrograph.php?wfo=box&gage=lowm3&view=1,1,1,1,1,1
