Clean Water Connections:
According to the District's Rules and Regulations:
No person(s) shall make connection of roof downspouts, foundation drains, areaway drains, or other sources of surface runoff or groundwater to a building sewer or building drain which in turn is connected directly or indirectly to a public sanitary sewer. Such drains will be connected only to a storm drain system within a separate building sewer.
Clean Water connections to the District's sanitary system is the most significant problem that the District is trying to deal with. Currently there are over 1100 customers in Waterville that are paying a quarterly surcharge fee for these connections. The large number of sump pumps and other clean water connections have the potential to overwhelm the Districts sanitary system during major rain events. The District has been lucky with only one known sanitary sewer overflow in the past few years, but we know that the capacity in our major interceptors during major rain events is at its maximum. This situation presents a significant problem for the future and if the clean water connections are not separated from the sanitary system then major multimillion dollar projects, like storage tanks or installation of larger interceptors, will be required which will have a significant impact on the rate payers.
Below is an example of how clean water connections effect the sanitary system. The chart shows what happened during a 5 inch rainstorm in 2018. The average daily flows for periods of time without rain in the District's Messalonskee Interceptor are close to one million gallons per day. During this significant rain event that continued for several days the peak daily flows exceeded thirteen million gallons per day and then stayed elevated for a number days following the storm. The huge spike in flows that happened during the storm is primarily inflow from clean water connections along with some infiltration and the elevated flows in the days following the storm is caused by both inflow and infiltration. The District and treatment plant can handle the inflow and infiltration that happens days after the storm, but reaches a point when it cannot handle the inflow spike during and immediately after the storm. Since the District's sanitary and storm drainage systems are 100% separated the majority of the inflow is caused by sump pumps and other clean water connections.
Property owners with clean water connections are strongly encouraged to separate them from the sanitary system. If there is not a significant reduction in number of connections the Board of Commissioners will be forced to impose stronger measures that may include a significant increase in the surcharge fee in order to avoid large multimillion dollar solutions that will impact all rate payers.
Upon request District personnel will be happy to meet with customers to discuss possible solutions for disconnecting their clean water connections. Once disconnected the surcharge will be removed from the customers quarterly bill.
