Measuring rainfall provides BWSC with important data used in monitoring the efficiency of our sewer and drain systems during storm conditions. We use this information to evaluate the capacity of our infrastructure and plan proactive maintenance projects. This data can assist in monitoring stormwater runoff into Boston Harbor and the Charles, Neponset and Mystic Rivers.
BWSC maintains solar powered rain gauges on top of buildings throughout the city. These gauges log measurements of precipitation and report data every five minutes. BWSC provides this information and uploads this rainfall data on a regular basis. BWSC reports rainfall data as far back as 1999, depending on the year of installation for the various gauges.
PLEASE NOTE THAT THE RAIN GAUGES IN ALLSTON, DORCHESTER-ADAMS, AND DORCHESTER-TALBOT (MATTAPAN) ARE CURRENTLY OUT OF SERVICE. BWSC IS WORKING TO BRING THESE GAUGES AND THEIR DATA ONLINE AS SOON AS POSSIBLE. WE APOLOGIZE FOR ANY INCONVENIENCE, AND RECOMMEND THAT YOU CHECK A GAUGE IN AN ADJACENT NEIGHBORHOOD TO GET READINGS FOR THE NEIGHBORHOODS AFFECTED BY THE RAIN GAUGE SERVICE ISSUE .
Also note that the daily rain gauge measurement function - which is updated every five minutes - is set by default to Eastern Standard Time (EST). From now until the end of Daylight Savings on November 3, 2019, add one hour to the most recent rainfall reading to get a true real-time measurement of precipitation.
Although the Commission calibrates these devices on a regular basis, they are subject to inaccuracies. Snow, hail, severe weather, and human tampering can affect the data. At the Commission's discretion, historic rainfall data may be adjusted as inaccuracies are identified and corrected.
Rainfall Data
Interactive - Yearly, Monthly, Daily, Daily Detail, 5 Day
Garden Tips and Garden Water Calculator
Use the garden water calculator to figure out if you need to water your lawn or garden and gather good gardening tips for a local garden.