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7 Warning Signs of a Full Septic Tank

Maintaining a smoothly functioning septic system is a crucial yet often overlooked aspect of homeownership. With many households relying on septic tanks to manage their wastewater, the warning signs of a full septic tank should never be ignored. Failing to address these warnings promptly can lead to messy, expensive, and potentially hazardous situations.

As a professional septic pumping company, we are often asked by customers for signs to look out for. In this blog post, we will share 7 warning signs of a full septic tank. If you do recognize any of these, it is time to call in the professionals. Proper maintenance and timely inspections by a reputable septic tank pumping company are crucial to maintaining the health of your septic system.

full septic tank being pumped

1. Slow Draining

When monitoring your septic tank levels one sign you will notice is that your sink, toilet, and drains are taking a long time (more than a minute) to drain.

Slow draining or flushing can also be the result of other issues, such as drains being clogged by hair, dirt, or paper products. But if you are noticing this in ALL of your drains and toilets, then it is likely not just a local clog and it is time to call a septic pumping company to check that your septic tank is not reaching its capacity.

2. Gurgling Sounds

The next warning sign is one that you won’t see, but hear. When you go to flush the toilet, use the sink, or drain the tub and you hear a gurgling sound, it’s time to look into your septic tank maintenance.

Gurgling happens when something is blocking the line and preventing the air from moving through. Hearing a gurgling sound coming from your pipes might indicate that air is trapped in the plumbing system due to a full septic tank.

3. Bad Odors

As you might assume, all of the wastewater going from your home into your septic tank wouldn’t have the most pleasant smell. But when a septic tank isn’t at full capacity, you should not smell anything at all.

If you are starting to detect foul odors coming from your drains inside or in the area around the septic tank this could be a sign of excess waste and sewage, indicating a full tank.

4. Pooling Water

If you are noticing pools of water and you haven’t had rain lately, your septic tank is likely taking matters into its own hands and emptying itself. Standing water or soggy areas in your yard near the septic tank or drain field, are a tell-tale warning sign that the tank is overflowing and unable to handle the wastewater properly.

5. Sewage Backup

This next warning sign of a full septic tank is one you don’t want to deal with, sewage backing up into your drains, toilets, or sinks. This is a clear indicator of a full or clogged septic tank because the wastewater isn’t able to drain away from your home so it is coming back up.

Keep an eye on your lowest-level drains (such as your basement drains) if they show any signs of being backed up you know it is time to empty your septic tank. Sewage backup is a biohazard, so it is a serious issue and requires immediate attention from septic tank professionals.

6. Lush Grass

This next indicator might seem counterintuitive- if the grass around your septic tank or drain field is unusually lush and green, especially compared to other areas of your yard, it could indicate that the tank is full.

The extra water and nutrients from the sewage tank are feeding your grass and plants, giving it that noticeably healthier look. Although it might look nice, this is a sign that your septic tank is either full or leaking- so it is time to call in the septic tank company.

7. Changes in Flushing or Water Usage

This next point is less of a warning sign and more of something to be aware of before you get to any of the above stages. If you've recently increased the number of occupants in your household or have had a sudden increase in water usage (e.g., hosting a large gathering), your septic tank might fill up more quickly, leading to these warning signs. Remember septic tanks should ideally be pumped every 3 to 5 years, but this is varied based on usage.

full septic tank being pumped

What to do if you recognize the warning signs of a full septic tank?

If your household is running on a septic system it is crucial to keep on top of regular maintenance and inspections in order to avoid an overflowing tank. Slow draining, gurgling, bad odors, pooling water, lush grass, and sewage backup are all warning signs of a full septic tank. If your household has had a sudden increase in water usage or occupancy make sure to be on the lookout for any of these indicators of a full tank.

Septic issues are not ones that should be handled by the homeowner and need to be addressed by a certified professional. If you are experiencing any signs of a full septic tank, you need to reach out to a reputable company.

Black Diamond Pumping is a Northern Colorado septic pumping company with over 20 years of experience serving both residential and commercial customers. If you are needing any services, our certified technicians are able to install, maintain and inspect septic tank systems. Please contact us today to see how we can help get your tank in optimal working condition.


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