Federal regulations at 49 C.F.R. §192.383(d) regarding gas pipeline safety requires Unitil to notify customers of their right to request installation of an Excess Flow Valve (EFV) on their existing gas service line under certain circumstances. An EFV is a mechanical safety device installed inside a gas service line between the gas main in the street and the gas meter. The EFV is designed to minimize the flow of natural gas in the event of a service line break. A potential benefit is, in the event that an excavator accidentally digs up the gas service line, the valve would operate to minimize or shut off the flow of gas.
If the customer’s service line operates at a pressure of less than 10 pounds per square inch gauge throughout the year, the customer’s service line is exempt from EFV installation. An exemption will also apply if: a customer’s load exceeds 1,000 standard cubic feet per hour; the operator has experience with contaminants in the gas stream that could interfere with the EFV’s operation or cause loss of service to a customer; there is a potential for interference with necessary operation or maintenance activities, such as blowing liquids from the line; or an EFV meeting the performance standards in federal rules (§192.381) is not commercially available to the operator.
EFV Conditions & Information
EFVs do not operate on all gas service lines and certain parameters may exist where installation of an EFV is not warranted. Many customers already have an EFV installed on their existing service line.
To install the excess flow valve, Dig Safe notification is required, and Unitil will excavate the service line at its connection to the gas mainline piping that runs along the street. Unitil will then turn off the customer’s gas service line, install the excess flow valve, backfill the excavation and relight the customer’s appliances. Typically, within a few weeks a restoration contractor will return to restore the customer’s property. Under certain conditions Unitil may need to replace the entire gas service at no additional cost.
Customers must pay a basic installation charge of $2,000-$4,000, depending upon specific circumstances. Additional costs may apply based on location-specific installation needs. Individual estimates will be provided upon request.
The Massachusetts Department of Public Utilities (“MDPU”) is currently reviewing a request by Unitil to allow the EFV to be installed without a direct charge to the customer. Customer requests for EFV installations will be scheduled to occur after the MDPU’s final decision on payment responsibility in compliance with the MDPU’s decision.
To inquire about having an EFV installed on your gas service line, call our customer service center at 888-301-7700.