With all the attention development proposals and options for new zoning are receiving, there has been renewed interest in the status of the Town’s drinking water and sewer systems. These utilities are often taken for granted but they are critical parts of our infrastructure that provide essential services to residents.
Thanks to the foresight of community leaders decades ago, the Town has a fairly robust water system. The Town purchased Gravely Pond and the surrounding lands that straddle the Manchester/Hamilton town line for the purpose of preserving an important watershed for the Town’s drinking water supply. Even before this, conservation efforts began in the 1870s to preserve Cedar Swamp and its environs which feed Sawmill Brook and the Town’s well further downstream at Lincoln Street. These two sources supply us with our drinking water.
Back in 1985 the state issued what is called a registration certificate for the Town’s water system. Given that no detailed capacity studies were done at the time, the state issued a daily withdrawal amount as part of the registration most likely based on an average of preceding annual usage. Our daily registration number is 0.72 million gallons a day (MGD). If water use consistently exceeds the registration number by over 0.1 MGD the state will require action be taken to seek a more formal permit with the requisite additional studies and system improvements. Over the last 36 years our daily average consumption of water has been on either side of 0.72 MGD, typically within plus or minus 10 percent. The average for the last four years has been under our registration number. Even in drought conditions and high annual consumption our water supply has always been adequate.
Obviously, there have been new homes built during this time but with more efficient fixtures and improvements to the water pipes reducing leaks, our actual usage has not materially increased. A large percentage of total water use in town goes towards irrigation. Summer use is some 2.5 times higher than winter use with some very large users skewing the average household consumption calculations. Dryer seasons drive up water usage more than any other factor. It is likely that the state, as part of their registration renewal process, will require us to reduce the amount of water going toward irrigation. (Using drinking water for irrigation is increasingly frowned upon.)
A few years back we were losing as much as 40 percent of our water through leaking pipes and major breaks. We have cut this nearly in half as we replace pipes and valves throughout the system. We will continue to make improvements which will further reduce our annual usage. Other improvements, including using recycled water as part of the treatment process at the sewer plant rather than fresh drinking water, and accurately tracking the water that is returned to Gravely Pond as part of the plant operations, will further reduce our water consumption. These efforts should result in over 100,000 gallons a day in lower water use. (Household water use per state Title 5 regulations is calculated at 110 gallons per bedroom per day – actual water use tends to be significantly lower.)
Meeting future water demands will require continuing our pipe replacement work, finding new efficiencies in operations, and, likely through a state mandate, reducing irrigation use. We also have the possibility of contracting with Gloucester to serve the eastern end of town should we ever need to. Providing adequate water supply for current and future town residents is an obligation of the Town and one we are prepared to meet.
On the wastewater side of the equation, here, too, we have seen considerable investment and improvement over the past eight years. Our treatment plant is permitted to process 0.67 million gallons daily (MGD). Back in 2013 the state issued a consent order requiring system improvements because we had reached 80 percent of our permitted capacity over the previous 12 months. State requirements are that when a treatment plant reaches 80 percent of capacity a town must undergo an analysis of its system, remove unnecessary water getting into the system and complete a Comprehensive Wastewater Management Plan (CWMP).
The Town has completed the CWMP (though the state has asked for some updates) and has made good progress on removing infiltration and inflow. Through this work (primarily replacing or lining sewer pipes) we have brought our flows down to a daily average of some 0.45 MGD. Again, efforts continue to remove the unwanted infiltration and inflow which will further free up plant capacity.
The CWMP anticipates that most of our unused capacity will be for in-fill development within the existing sewer district. We will continue to rely on on-site septic for most areas outside of the sewer district, whether individual systems or possibly small communal systems. The benefit of this approach is that water replenishes groundwater levels rather than being released into the ocean as is the case with our sewer plant.
While municipalities can sometimes slow down growth to allow their utility infrastructure to catch up, these measures can only be temporary. Proper zoning and staying ahead of future demands are the tools best to use to guide the future development a community desires.