Henderson Municipal Gas Customer Notification: Excess Flow Valve

We would like to take this opportunity to notify you as a homeowner or small commercial business owner that installation of an Excess Flow Valve (EFV) on your property’s existing natural gas service line is an option available to you.    

What is an EFV and what does it do?

EFVs are mechanical shut-off devices that can be installed in the gas pipe (“service line”) that runs to the gas meter on your property. An EFV is designed to shut off the flow of natural gas automatically if the service line has a break or puncture. For example, during an excavation the line might be broken causing a release of gas. Stopping the flow of gas from a broken service line significantly reduces the risk of natural gas fire, explosion, personal injury and/or property damage.

What an EFV will not do?

As with all mechanical devices there are limitations. EFVs are not designed to close if a leak occurs beyond the gas meter (on house piping or appliances that you own). EFVs also may not close if the leak on the service line is small.

It should also be noted in some cases with the addition of high-use items such as an emergency generator or a pool heater the surge in flow may cause the EFV to close. If an EFV was in place and then additional gas appliances were added causing the EFV to activate, HMG would seek reimbursement to replace the EFV. Conversely, in the rare instance that the EFV fails due to manufacturer defect or for most causes beyond the property owner’s control there would be no charge for replacement.


As you might imagine EFVs are not free. The cost of an EFV installation will be at the expense of the customer. We will do our best to keep costs to a minimum and you will be billed only at our cost for material, equipment and labor. Each situation is different, but we would expect a range of $300 to $600 for a typical installation. We will perform an estimate upon request and seek your approval before completing the work. Please remember, this is an option made available to you and is not a requirement.  


We are sending this notice to you because our records indicate this address appears to have conditions acceptable for EFV installation. There may be instances where an EFV cannot be installed due to high gas flow or other factors, but for most residential and small commercial businesses an EFV would be available. To request an EFV installation you must be the owner of the property. Should you be the utility account holder and not the owner, please pass this information along to the owner or notify HMG of the owner’s mailing address.

If you are interested in having an EFV installed please contact us at 270-831-2493.  We will verify if the address can accommodate an EFV, and if so provide you with an estimate for your consideration.  Please feel free to contact us if you have any questions.