A Humble Task

For over twenty years, the Massachusetts Water Resources Authority has had the humble task of providing water and sewage services to about 2.5 million people in over sixty cities and towns. With the recent additions of the Deer Island Wastewater Treatment Plant as well as the John J. Carroll Water Treatment Plant, the MWRA does a superb job at dealing with sewage and the great demand for water. The water begins its very long journey in one of two locations, either the Quabbin, or the Wachusett reservoirs. Filled naturally by rains, snowmelts and other small springs, these reservoirs are protected to maintain the cleanliness and clarity of the water. Although our community of Wilmington does not get water from the MWRA, recent contamination has raised the question of whether or not to connect to their grid.

As the water makes its trek to be purified it generates power in the Wachusett Reservoir. The water for the Metro West as well as the Metro Boston cities and towns is treated at the new John J. Carroll Water Treatment Plant in Marlborough. The water goes through a rigorous cleaning process, which starts off with being disinfected with bubbles of ozone (03). Substances called chloramines, which can be any of several compounds containing chlorine and nitrogen, are added to prevent contamination in pipelines. A chemical called sodium bicarbonate (HNaC03), also known as baking soda, is added to maintain a healthy pH, which prevents the dissolving of pipes into the water. The water is further treated with fluorine, which strengthens the teeth of the drinkers. As for the Chicopee Valley area, the water is treated at the Ware Water Treatment Facility in Ware. It is disinfected with chlorine and chloramines are added to prevent contamination again. From these treatment facilities, the water travels towards the home.

The water for the Metro West leaves the John J. Carroll Water Treatment Plant through the MetroWest Water Supply Tunnel. From there it is stored in large tanks and is eventually led into smaller water mains until it reaches the communities. Water leaves Ware through the Chicopee Valley Aqueduct and goes from there to the towns, which then distribute it to homes. However, the water's trip to the faucet is only the beginning; afterwards it makes a long journey to be treated at Deer Island Wastewater Treatment Plant.
About half of the population of Massachusetts sends their sewage to the MWRA. The Massachusetts Water Resources Authority also has to deal with some water runoff from rain and snow. The water that goes down drains from showers and sinks goes into locally operated sewers. From there the water travels to interceptor sewers, which are operated by the MWRA. The interceptor sewers carry the water to the Deer Island Treatment Plant for cleaning and disinfecting.

The first step in the sewages refining is the removing of large debris like logs and trash. Afterwards, the water is pumped under the harbor to Deer Island. The water makes its way to what is called a grit chamber where sand and dirt are settled out of the mixture and sent elsewhere. The substance then moves to the primary settling tanks where the solids are separated making a sludge material. Afterwards oxygen is pumped into the water to speed the growth of organisms, which in turn consume the wastes and settle to the bottom of the tanks.

The sludge is transported to sludge digestion tanks where harmful bacteria are eliminated and the volume is reduced. After it is disinfected, the product is shipped to Quincy where it is converted into a fertilizer for agriculture. The waste water is further disinfected with sodium hypochlorite. After, sodium bisulfite is added to remove chlorine from the water. The chlorine removal ensures the safety of marine life upon the water's discharge. The effluent, as it is called, is transported to diffuser pipes in Massachusetts Bay, which eject the wastewater. Due to the rigorous disinfection process at Deer Island the water is environmentally safe, although the area is constantly monitored for problems.

Thanks to the MWRA a large amount of the citizens of Massachusetts are provided with water and sewage services. They give clean water that is essential to our well-being and they take away what can be harmful to us. Their high tech facilities are extremely effective and beneficial to Massachusetts. These facilities have effectively cleaned up Boston Harbor and restored its ecosystem and although many take the water and sewage system for granted, their work at the MWRA is welcomed with open arms.

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