It's Getting Watery In Here

Causes And Signs Of Gas Line Blockages

Pipe blockages are common with drain and water pipes. However, blockages can also affect fuel lines, such as gas pipes. Below are potential causes and signs of gas pipe blockages.


Anything that reduces a gas line's effective diameter can block efficient gas flow. Below are potential causes of such blockages.


Water causes gas line blockages both directly and indirectly. For the direct blockage, water gets inside the gas line via cracks and prevents gas flow. Alternatively, water can seep into the gas line and corrode it over time. The corrosion then restricts gas flow.

Dirt and Debris

Dirt and debris can get into and block gas pipes through cracks just like water. The blockage often occurs over time. Don't forget that gas pipes are not that big, and even relatively small dirt and debris reduce their effective diameters.

Tree Roots

Tree roots, a bane of drainage pipes, also affect gas pipes. Small tree roots can get into gas pipes through tiny cracks, grow, and eventually block the lines.


Like water, debris, and tree roots, small animals can only get into gas lines with existing openings. For example, insects can fly or crawl into your gas pipes and block them.


Physical damage to the gas pipes can reduce their diameter and restrict gas flow. Excavation or construction mishaps can cause such dents.


You should contact a plumber for professional diagnosis if you suspect gas line blockage. Below are telltale signs that might point to such blockages.

Inadequate Appliance Performance

Gas appliances malfunction or exhibit inadequate performance if they don't get enough fuel. The exact signs depend on the appliance. For example:

  • A gas water heater might produce inadequate hot water.
  • A gas stove might produce a low flame.
  • A gas furnace might produce sooty flame, struggle to stay light, and take too long to heat your house.

Under these circumstances, you should suspect a blockage if your neighborhood isn't experiencing a gas supply outage.

Gas Leakage

A blockage increases gas pressure inside the pipes. Extreme blockage can lead to extreme pressure that might damage the pipe and allow the gas to leak via weak points on the pipe. Such damage is especially likely with aging gas pipes. Therefore, you should suspect a blockage if you notice leakage, for example, because of a natural gas smell.

Gas line problems are not suitable for DIY servicing. Contact a plumber for diagnosis if you suspect gas line blockage or damage.