Treatment & Distribution System Improvements
The residents of the Town of Webster have been dealing with the frustrating issue of discolored water for a number of years. Discolored water can be caused by a number of conditions, one of the most common being unlined cast iron pipes that generate rust when they come into contact with settled water. Unfortunately, our groundwater also contributes to our problem with discolored water. High levels of iron and manganese can be found in groundwater sources throughout New England so we are not alone in this problem. We need to treat our water to control these levels while also balancing our need to maintain a chlorine residual in the distribution system to control bacteria. Unfortunately, the chlorine required for disinfection also causes the iron and manganese to oxide and discolor the water. Please know that we work diligently to ensure that all of our water treatment programs are beneficial to public health. In our Town's case, the unfortunate side effect of unlined pipes, iron & manganese, and chlorine is discolored water.
So how do we make our water clean? We're happy to inform you that we are at the beginning of Step 1 of a 2 step process: Step 1 is to construct a Water Filtration Plant to remove unwanted natural elements from our water. Step 2 will involve upgrading our water distribution system to either line our unlined cast iron pipes or replace them.
Memorial Beach Treatment plant
The bidding process for the construction of the new Water Filtration Plant was recently completed and the contract was awarded to a qualified contractor. The contractor, Robert B. Our, mobilized to the Memorial Beach site in March, 2018 and has begun construction activities. It is anticipated that the treatment plant will be completed, and fully operational in June, 2019. The facility will remove the elevated raw water concentrations of iron and manganese levels from both Station #1 and Station #2 before adding the necessary chlorine disinfection as it enters the distribution system.
water main replacement program
This year, we are planning to initiate a comprehensive cleaning and lining program of our unlined cast iron pipes. We have come up with a prioritized list of streets where we will be conducting this work. The work will involve scrapping the interior of the pipes, and then either spraying or inserting a liner that not only creates a barrier between the water and the iron pipe, it also increases the pipe’s ability to transport water during high flow periods (i.e. fire-fighting). Some sections of Town will require the replacement, or addition, of water mains to increase fire flows. This will be a long-term project since the majority of our system (50% - 40 miles) is unlined cast iron and will likely take several separate funding efforts to complete.
The graph below shows that roughly 25% of Webster's distribution system is over 90 years old. In 2001, an American Water Works Association study called “Dawn of Replacement” pointed out: “The oldest cast iron pipes—dating to the late1800s—have an average useful life of about 120 years. This means that, as a group, these pipes will last anywhere from 90 to 150 years before they need to be replaced, but on average they need to be replaced after they have been in the ground about 120 years. Because manufacturing techniques and materials changed, the roaring ’20s vintage of cast-iron pipes has an average life of about 100 years. And because techniques and materials continued to evolve, pipes laid down in the Post-World War II boom have an average life of 75 years, more or less. Using these average life estimates and counting the years since the original installations shows that these water utilities will face significant needs for pipe replacement over the next few decades. Replacement of pipes installed from the late1800s to the 1950s is now hard upon us, and replacement of pipes installed in the latter half of the 20th Century will dominate the remainder of the 21st. We believe that we stand today at the dawn of a new era—the replacement era—for water utilities". In summary, a portion of the buried infrastructure has reached the end of its expected useful life and has reduced flow capabilities due to iron tuberculation (see picture of water main from Goddard Street). Rehabilitation of these mains will improved flow characteristics and extend the life-cycle of the pipe an estimated 60-80 years.
At the April 9, 2018 Board of Selectman's meeting, the Water Department presented information regarding the water main replacement program and the current status of the water budget. Here is copy of the Capital Improvement Plan Update Presentation, and below is a link the Selectman's meeting presentation.