The Board of Water Commissioners is planning to hold an open house at the new water treatment facility on May 11th from 9 AM to 1 PM.  All Topsfield residents are welcome to attend to tour the new treatment facility.  

May 13th Update: The open house was well attended.  Don't worry if you missed it as we're happy to give tours for residents by appointment.

Our water system uses groundwater wells to supply water for our customers.  The water undergoes a variety of treatment processes to improve its quality in order to meet drinking water regulations. 

The first process is natural filtration through the sand and gravel deposits near the wells.  As water travels from the land surface towards the wells, the naturally occuring sand and gravel deposits filter out many contaminants including coliform bacteria, vegetative debris, and others that are commonly found on the surface of the ground or in nearby surface water bodies.

Once the water is in our supply system it travels to the water treatment plant for additional treatment including disinfection, pH adjustment, greensand filtration, aeration, fluoridation and sequestration/corrosion control.  The raw water is treated in the following order:

1. Sodium Hypochlorite Pre-treatment: Chlorine is added to the water as it arrives in the plant disinfect the water.  Chlorine is also an essential component of greensand filtration becuase it is the primary oxidant used to remove manganese.  The pre-filtered water typically has a free chlorine residual of around 0.75 milligrams/L (mg/L).
2. Pre-treatment pH Adjustment: The pH or acidity of the water is reduced prior to filtration.  The pH of the raw water, normally around 6.5-6.6, is raised to 6.9 using potassium hydroxide.
3. Potassium Permanganate Pre-treatment: We have the option of using potassium permanganate to oxidize the manganese but it is not in use at this time.
4. Greensand Filtration: The water is passed through filter vessels with a layered media including anthracite, Greensand Plus and gravel.  The Greensand Plus traps any manganese in particulate or soluble form and removes it from the water.  This step also removes iron but we typically have very little to no iron in the water.
5. Aeration: The water is pumped through an aerator which strips out carbon dioxide to reduce the amount of dissolved inorganic carbon and further increase the pH of the water from 6.9 to 7.5.  This step improves corrosion control and raises the pH without chemical addition.
6. Fluoridation: Once out of the aerator, fluoride is added to the water to maintain a level of 0.7 mg/L of fluoride.  This step is intended to prevent tooth decay.
7. Pre-clearwell Disinfection: We have the option of adding more chlorine before the water enters the clearwell.
8. Clearwell:  The water enters a baffled clearwell arrangement that provides more contact time for the disinfection process.  This allows us to produce water that has a lower and more stable chlorine residual when it leaves the plant.
9. Post-treatment pH adjustment: We have the option of increasing the pH of the water just before it leaves the plant.  This is not currently used but will be required when the aerator is undergoing maintanence.
10. Phosphate: A ortho/poly-phosphate blend is added to the water as it leaves the plant. This formulation was used to sequester manganese but also has corrosion control benefits.

Hydrant flushing will begin on April 8th. We'll flush for a week and then take 2 weeks off for Easter and resume on April 29th.  We plan to follow the normal route which is posed onlne at flushing.topsfieldpublicworks.org

Flushing removes sediment from the water mains, identifies hydrants in need of repair and checks system fire flows. Customers will have rust colored or black water while the water mains are flushed and for a period afterwards. The work will be conducted on weeknights from 9 PM until 1 AM to minimize the disruption. We apologize for the inconvenience.

Manganese levels in areas being flushed will be higher than normal and may exceed levels described in the drinking water advisory issued in November 2013. Do not drink, cook or make formula with the discolored water. Avoid using hot water while the cold water is discolored. Doing so will allow sediment to accumulate in your hot water tank and will take longer for the hot water to clear.

This is the first round of flushing to be done since the water treatment plant started operation.  It will probably take a couple of rounds of flushing before all of the sediment is removed from the distribution mains.

The Town appropriated $10.4 million on June 20, 2017 for the construction of a water treatment plant and associated piping.  Substaintial completion of the project is expected in January 2019 which will be followed by several weeks of testing.  We're planning on using the plant to produce water by the end of February 2019.  Progress updates will be posted on a regular basis.

March Update: The plant is now fully operational and has been treating all of the Town's water since March 6th.  It will take several cycles of hydrant flushing to clear out the sediment in the water mains but manganese is no longer being pumped into the distribution system.

We conduct hundreds of water quality tests each year. Results are now available on our Water Quality Site which includes information about which water sources are in use. The site has been under development for several years and more functionality will be added as time permits.