The MWRA Water System

"Where does our drinking water come from?" you might ask. Well, the Massachusetts Water Resources Authority gets its water from the Quabbin Reservoir as well as the Wachusett Reservoir. There are 220 million gallons supplied each day. But don't worry. Both reservoirs are protected and often tested by the Massachusetts Department of Conservation and Recreation. Now you may want to know how the water gets from the reservoirs to the tap.

The journey of MWRA's drinking water starts at the Quabbin and Wachusett reservoirs, as stated earlier. This water travels through many steps in order to be suitable to use in our homes. First of all, ozone gas bubbles, safely and naturally, disinfect the water. Then chloramines are used to prevent contamination to the water. Next, sodium bicarbonate adjusts the pH level of the water. Lastly, to maintain a good dental hygiene, fluoride is added. The water then leaves through the Metro West Water Supply Tunnel and kept in large tanks. Then into distribution mains it goes and to your community.

After the water is used in your home, it becomes waste- water (which are all the fluids that go down a drain). First, the wastewater is collected and pumped into various "headworks" where it is then rid of large objects such as bricks and logs. Next, it goes through a grit chamber where the mud and sand settles out. This is called preliminary treatment. Primary treatment is when sewage enters the primary settling tanks and 60% of the solids are removed. Lastly is the secondary treatment. This is when micro-organism growth is sped up with the help of plant oxygen. The microbes ingest the waste of the wastewater and settle on the bottom of the tanks. This new wastewater is then disinfected and let into the Boston Harbor. All the sludge from the tanks is brought to the Quincy pelletizing plant where it is made into fertilizer pellets.

The MWRA carries out the journey of water very appropriately. From the Quabbin and Wachusett reservoirs to treatment. Then to our communities it travels. And finally down our drains and once again treated before entering the Boston Harbor. Our water is taken especially good care of by the MWRA and without them we wouldn't have the water we use today.

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