How does Scituate know they will have enough water supply to allow for streamflow releases from the reservoir? The NSRWA and partners have done extensive modeling of the First Herring Brook (the water supply for the town of Scituate) and the current town water demands, and have determined that even during the worst droughts of record the recommended streamflow to be released will safely maintain the water supply under current demand. As a supplement to this modeling and to ensure that “real time” conditions are being used, the NSRWA has developed a water supply and streamflow release prediction tool.

The tool uses current conditions to predict whether the reservoir will stay above 20% full by October 15th, which is when the reservoir typically starts to refill. This tool uses the volume of water in the reservoir to determine the number of days remaining until a water ban should be enacted and/or streamflow cut off. It requires weekly inputs of two pieces of information from Scituate’s Water Division – the previous week’s average surface water pumping rate and the reservoir level, plus any relevant changes to the baseline condition.

Since we cannot see a drought coming, this tool will provide the town with up-to-date feedback on the system’s conditions and is being piloted this year. We have found that summertime water conservation (i.e. not using water excessively outdoors) makes a large difference in how

successfully water can be released for minimal flows and ensuring adequate supply during a drought; the best solution for maintaining a healthy drinking water supply is to reduce nonessential water use during the summertime.