Water Measurement (IMAGE) Virginia Tech Caption This weir, a place in a stream where a wall controls the flow of water, measures stream flow and dissolved chemical exports from Watershed 3 at the Hubbard Brook Experimental Forest in New Hampshire, where the study took place. Credit Virginia Tech Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.