Billerica Water Works Overview

Billerica Water Works was established by an act of the Massachusetts Legislature in 1897. Construction of the original works began in 1898 and continued for several years. The water works was first activated in January of 1899. Water was at that time drawn from wells located in the area of the present Water Treatment Plant, where the original pumping station building remains.

Treatment Plant
The first Water Treatment Plant (WTP) was built in 1955. As originally built it had a capacity of 3.5 million gallons per day (MGD) and was intended to be expanded to 7 MGD at a later time. In 1967 the plant was expanded to its intended maximum capacity. As growth in Town continued the plant's capacity was again increased in 1976, this time to 14 MGD.

On May 18, 2006 the old Water Treatment Plant on Boston Road was taken off line  and the new Water Treatment Plant, located off Treble Cove Road, was brought on line.  The new Water Treatment Plant uses the same processes and has the same capacity as the old plant. The old plant was eventually demolished.

Over the years some of the processes have changed.

1) In the 1979 the Powdered Activated Carbon applied in the pretreatment was replaced by changing the filter media from anthracite coal to Granular Activated Carbon.  This lowered cost and reduced sludge volume.

2) In the 1987 sodium hydroxide was replaced with potassium hydroxide and in January 2009 a switch was made back to sodium hydroxide.

3) In December of 1992 fluoridation of the Water Supply began.

4) In May of 1997 an ozone generating and feed system was installed. This was done to remove the manganese which caused "brown water". This treatment also reduces taste and odors and very effectively inactivates virus and cysts.

5) In September of 1999 ammonia was added to change the secondary disinfectant to from free chlorine to chloramines. This was done to lower the trihalomethane levels. This adjustment has been very successful.

Treatment Plant Operations
The Water Treatment Plant is designed as a continuous process, therefore it runs twenty-four-hours-a-day, seven-days-a-week. The Treatment Plant is normally shut down only for maintenance, severe storms, and power failures.

The Filter Operators monitor the process by checking chemical use periodically and bench testing water from various parts of the treatment process every other hour. The Filter Operators also receive bulk chemical deliveries. Daily chemical handling involves transferring of chemicals from storage to day tanks. The operators also perform maintenance on some of the control systems as needed. They adjust the treatment rate according to changes in the standpipe water level, which is a reflection of water consumption by our customers.

The laboratory staff performs the equipment calibrations and non-daily testing. Most critical of these are the bacterial samples collected and analyzed each week from ten DEP-approved sites in the distribution system. The laboratory staff also collects the many samples required to comply with the Safe Drinking Water Act. and writes the annual Consumer Confidence Report.

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