Septic Tank: Warning Signs of Leaks or Damage

Warning signs of a septic tank leak or damage includes foul odors, overly lush vegetation and toilets backing up. Older systems and even a new system may have issues. Systems may work fine for years, then the home gets a new family living in it, with different cooking, showering and laundry habits which can cause a system failure.

“Yellow” and “Red” Flags

Foul Odor

Odors of sewer gases or a sewer water stench can come from a septic tank lid out of position or damaged, from septic a tank riser or filter access port. If the tank body is cracked, deteriorate or holed – gaseous odors may escape.

They may be noticeable over a long period of days or time, not just for a few minutes. Where are the odors the strongest; near the tank, leach field or from your neighbors tank if it close by. Remember, the odor may be coming from the leach or drain field and not from a damaged tank.

Lush vegetation

Lush vegetation is not always a sign that you’re at a luxury resort. It can be a warning of a leaking tank. It may also be from the system overflowing or a pipe near the tank that has cracked or come loose. If there is a filter that is clogged or leach field clogged, then a wet soggy area may develop in the tank or leach field area.

Overly soggy yard

If the yard is overly soggy, especially near the septic tank, then there may be a leak. If there is a yard sprinkler system and the timing is off and the system runs for long, long periods of times, you may also have soggy spots in the yard.

Standing water

Soil tends to compact over time when exposed to wet conditions. If a tank has a leak, the water from the leak  may cause the soil near the tank to settle and drop down, especially if the area around the tank had a lot of loose back fill put in after the tank was placed in its’ hole. When the soil settles and drops down some, it allows surface water from the rains and sprinkler systems to puddle or stand.

Odor or overly wet areas may not be from a damaged or leaking septic tank

Should a sewer line near the tank be cracked or damage, then the sewer waste may be creating the problem. Sewer lines are usually placed in a trench going to the tank from the house. If leaking over a period of time, the trench itself may be acting like a ditch and allowing the waste water to migrate toward the septic tank.

Toilets or sinks backing up or slow draining

This can be a warning at times that the septic tank is damaged. Tree roots may blocked and damaged the area where the effluent water exits the tank. A baffle may have collapsed or created a blockage, perhaps causing the leach field to fail which may back up the tank or sewer lines.

If  the toilet or sinks are backing up – Video the sewer line first

Before pumping and inspecting the septic tank, some people recommend that the sewer line from the house to the tank be videoed. This will show if the line is cracked, clogged, offset or collapsed. There could even  be tree roots creating the problem. ( READ ABOUT VIDEOING SEWER LINES )

A “Sludge Judge”

When a septic tank is too full of sludge and scum, it will not function properly and may back up toilets and sinks. Septic tank inspectors and pumping companies often use a “Sludge Judge” to help determine the amount of sludge, scum and effluents in a tank. When the sludge and scum exceed 1/3 of the volume, then the tank may fail and probably should be pumped.

David Jones - General Contractor, Home Inspector, Consultant

David has over 45 years’ experience as a general contractor, inspector and professional instructor. He writes articles for homeowners, new home buyers and Real Estate Agents. Read more