King Street Water Quality

The DPW has struggled to maintain high water quality on King Street and in the neighborhoods off of it.  This is because King Street and its neighborhoods are a dead end water main at the far western side of the Town, away from all three of the Town's water treatment plants.  Water that enters this main has nowhere else to go and when a pocket of water with color enters the main, it only gets better when the water is used up or is flushed through operational flushing. 

The two biggest problems are occasional color and low chlorine.  What causes these problems?  Iron.  From the water system's creation in the 1930's thru the opening of the Pond Street water treatment plant in 1973, water was pumped untreated, with the exception of the addition of chlorine, directly into the water mains.  The groundwater was typical of groundwater in New England, high in iron and manganese and, depending on which wells were in use, sometimes high in organic color.  Some of the iron and manganese oxidized and deposited on the sides of the original cast iron water mains forming hard tubercules.   Some iron and manganese oxidized and deposited on plumbing fixtures in customer's homes, leaving brown and black stains.  Over time, the town invested in treatment systems to remove iron and manganese, slowly improving water quality.  In addition, the water industry went away from using cast iron pipes to other materials that were less likely to have tuberculation issues.    We have tried to managed the ongoing deposits of residual iron oxides through system flushing. 

When the town switched to chloramines in 2020 to control the formation of disinfection byproducts,  we saw an increase in chlorine levels in the far ends of the water distribution system.  This is a good thing as chlorine controls the growth of bacteria in the system.  Certain types of bacteria can make people very sick, so the presence of chlorine is a positive thing.  Unfortunately, the chlorine seems to be softening the tubercules which are releasing iron and then re-oxidizing the iron, causing the iron to rust and ultimately cause discolored water.  The solution to this problem is either the replacement of the cast iron mains or changes to the water chemistry (mainly increasing the pH of the water) to make the water less likely to bleed iron from the tubercules.   We are in the process of designing and permitting the necessary chemical feed systems to achieve a higher pH.  With the cost of pipe replacement at $300-$400 per foot, the Town needs to be careful where we target main replacements in order to keep the cost of water affordable for all of the rate payers.  Some cast iron mains are perfectly fine and do not need replacement.  

King Street and the neighborhoods off of it are served by a variety of water main types and sizes.  King Street currently has a ductile-iron water main from School Street to Briarwood Drive.  We recently obtained funds at the May 2023 Annual Town Meeting to replace the old cast iron main from Briarwood Drive to the Hanson line which should ultimately help with water quality as well as reduce the likelihood of water breaks on that stretch of King Street.

We recently discovered that there is a short stretch of cast iron main running parallel to the ductile iron main on King Street from School Street to Industrial Way.  There are several customers being served by this main.  We plan to move these customers over to the ductile iron main and eliminate this section of cast iron main later this year.   We have also recently installed a network of sampling stations on Circuit Street, School Street, King Street, and Briarwood Drive to allow us to better understand water quality in the area and how the water changes as it progresses down King Street.  This information will help us target future water main replacement efforts.  Our currently plan is to sample these stations twice a week to build a better picture of the the problem as well as to help us target our flushing efforts.    The data will also help us determine if redirecting flow through valve changes will help us improve water quality. 

In the interest of transparency, we provide the sampling data below.  We caution the user to not read too much into individual samples as sampling techniques can stir up sediments and not necessarily provide a representative picture of the current water quality.   The body of data should be looked at as a whole as we are doing to get a complete picture of the problem as well as possible interim and permanent solutions.

Sept 2023 update

Engineering to add pH adjustment equipment to the Beal Water Treatment Plant is underway.  The firm conducting the work is hoping to complete its work and have permits by mid winter of 2023-2024.  Depending on the cost of the upgrades, we hope to slowly start raising system pH sometime in the spring of 2024.  This will help stabilize the bleeding of iron deposits from the older cast iron mains.

King Street and the neighborhoods off of it are fed from both the School Street water main and the Circuit Street water main from West Hanover Square.  Based on the data we have collected, it appears that the Circuit Street main is the dominant main and appears to be the primary contributor to the iron and color issues on King Street.   The water from the sampling stations at School and Circuit as well as the water at Gem Gravure at School and King is consistently better than all of the other sample locations.  As such, the DPW has submitted a capital proposal to replace the Circuit Street water main from West Hanover Square to King Street and then on King Street from Circuit Street to School Street.  This project is currently in the early stages of design and is estimated to cost $2 million.  If it is approved through the capital planning and Town meeting process we hope the project can take place in the summer or fall of 2024.  In addition, we altered valve positions to feed King Street exclusively from School Street.  This work took place on 9/14/23.  The test results since 9/14/23 for iron and color have been much more consistent from School Street all the way to Briarwood Drive.  This is encouraging.   Altering gate valve positions will not eliminate dead end mains but we believe it will provide better water for King Street and while it may create a few more dead end main segments, these segments will be easier to monitor and flush.  Please check back for test results. 

The Town has awarded a contract to replace the cast iron main on King Street from Briarwood Drive to the Hanson town line with a cement lined ductile iron main.  The project is expected to start in the middle of November and proceed for approximately 6-8 weeks.  Once completed, it is our expectation that the water on King Street from Briarwood to Hanson as well as in the neighborhoods off of this section of King Street should improve and will likely match that which we are now seeing in the vicinity of Briarwood with lower color and iron.    

Available Data Downloads:

King Street Water Quality Data 12-21-2023 (PDF File)

King Street Water Quality Data 12-21-2023 (Excel File)