Rainfall Data

rainfall collection device
Solar powered rain gauge.

Measuring rainfall provides the Boston Water and Sewer Commission 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. Environmental agencies and academic institutions also access this data for various research purposes, such as monitoring storm water runoff into the Boston Harbor and Charles, Neponset and Mystic Rivers. The Commission makes this data available to the public as well.

BWSC maintains solar powered rain gauges on top of public buildings throughout the city. These gauges log measurements of precipitation and report data every five minutes. We provide this information on the Commission's website and upload this rainfall data on a regular basis. The Commission reports rainfall data as far back as 1999, depending on the year of installation for the various gauges.

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 time is not adjusted for daylight savings.