How to Fix a Cracked Septic Tank

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How To Fix A Crack In A Septic Tank

Septic tanks are typically well-designed and constructed from reinforced concrete or fiberglass, but, expectedly, exposure to shifting ground conditions, season changes (freezing and thawing), or other environmental factors over the years can result to cracks. It is also possible for an inlet pipe feeding waste to the tank itself to have become problematic, leading to signs of septic failure. At the early signs of the above-mentioned, you should promptly seek professional help to properly diagnose the entirety of the problem. Sometimes, cracks in a septic tank can be repaired easily, but know that it is possible, too, that these are just early warning signs that the rest of the septic system is in trouble and requires your immediate attention.

Besides that submitting your septic system to annual inspection and regular maintenance is just good sense, septic tank inspections are important is because they catch problems with cracks that may have developed. A concrete septic tank can crack due to age, earth movement, the quality of concrete mix used, or due to sub-par installation. While older concrete tanks may be more susceptible to cracking, fairly new tanks can likewise develop cracks, especially because of poor fabrication or installation.  Cracks in the septic tank potentially allow groundwater to seep into the tank and sewage to leak out, so these cracks must be repaired immediately. Here, we will take a look at how to fix a cracked septic tank.

Repairing Cracks in a Septic Tank

Before the use of fiber plastic tanks, septic systems were typically designed to work with concrete tanks. Most septic tank systems installed before the early ’80s were constructed from concrete. As the cement tanks age, small cracks can develop anywhere in the entire system. Generally, these small cracks are normal and do not truly pose a major problem – unless they enlarge to a point where raw sewage is allowed to seep out of the tank, that is. During a professional inspection, the severity and location of septic tank cracks will be taken into account for proper diagnosis. Most tanks that are inspected normally pass inspection, but in severe circumstances, replacement of the tank may be necessary.

Septic tanks made of concrete will – expectedly — eventually develop cracks and leakage as they age. Concrete tanks can become a health and environmental hazards if not adequately monitored and maintained.

When a concrete septic tank has cracked, this potentially causes leaks which pose a real danger of soil contamination. Minor cracking and/or leaking means the tank may still be repaired and sealed, affording you a few more years to the tank’s life. It is recommended that you contact a septic service provider to pump the tank and inspect the damage (or damages) and determine if the problem is minor enough that it can still be repaired. If your septic provider has confirmed the viability of repairing the cracked septic tank, the process will likely be as follows:

First, the tank needs to be pumped out and cleaned. You need to give the cleaned-up septic tank time to dry out before the cracks can be filled. Even with an empty and clean tank, the contractor has to use special equipment for the process, as entering the enclosed space of a septic tank can be fatal due to toxic gases and fumes. Always bear in mind that the septic tank is a real biohazard and a high-risk working environment, and this is why you should let professionals handle it. Cracks in the tank are filled with cement or crack filler and allowed to cure. At the end of the repair process, it is wise to have the rest of the septic tank inspected for leaking and other damage. The shifting of the concrete might also cause damage to its baffles, so these will need to be inspected, as well.

Since you don’t ever see the inside of your septic tank, you won’t be able to see cracks when they develop. This is why regular inspection and pumping is crucial. Yes, as mentioned, you may not have to deal with a cracked tank (when the cracks are very minor), but you should nonetheless be aware of the signs that a crack (or cracks) has/have occurred. If you smell sewer gas in your home or building or anywhere within the property or notice that sewage is leaking into your yard, you should call your trusted septic professional for an inspection and prompt diagnosis for possible repairs.

Cracks on a septic tank can occur in many ways. Septic tanks located in areas that experience earthquakes (such as California) are more prone to cracking than those in other areas. Therefore, if you reside in an area that experience earthquakes more frequently, your septic tank should be inspected more frequently than the average prescribed. Also, if your septic tank is buried underneath where cars, heavy equipment, machinery, or a built structure (like sheds, garages, or above-ground swimming pools), know that these can all contribute to cracks developing in your tank. This is why it is never advisable to bury your septic tank where there is traffic atop, nor should you build over it.

Again, cracks in a septic tank don’t always require fixing. If the cracks are tiny and nothing leaks through (in or out), they might be left alone. On the other hand, severe cracks or heaved concrete may mean that the tank needs to be replaced. If the cracks in the tank allow leaking but are not too large, your contractor may simply fill them with concrete filler (or resin coating, for fiberglass tanks). Your contractor should be able to tell you if or not your current septic tank can still be saved.

Before septic tank repairs actually begin, your contractor will likely determine the cause (or causes) of the cracking. If it’s because of some persistent issue, then cracks will likely recur down the line. In which case, your septic contractor might recommend to move the tank or address the ongoing cause, if at all still possible, so no cracks will develop after repairs have been done.

Septic tank systems are designed to last many decades – with proper maintenance and routine inspection practices, that is. Regular inspection and periodic pumping are huge steps to ensuring the stability, functionality and safety of your dedicated on-site sewage treatment system.

Why You Should Repair a Cracked Septic Tank

Cracks in a septic tank, small though they are, potentially pose a danger to the entire system. Over time, these tiny cracks may aggravate and

  • Allow sewage to leak out of the tank and into your physical surroundings. Aside from this being unsanitary, this exposes everyone in the property to health risks.
  • Allow groundwater to seep into the tank. High liquid levels inside a septic tank may overwhelm the whole septic system, possibly resulting in gurgling, unpleasant odors, soggy patches in the yard, slow drains and flushes, among other more troublesome sewage issues.
  • Release bacteria, toxic sewer gases, viruses, and other contaminants to the surface and nearby groundwater sources. The hazards from a faulty septic tank are not just contained within your property’s boundaries and can endanger a significant number of outsiders, as well. 

Furthermore, cracks in the septic tank lid itself can be a major problem and should be addressed just as promptly since this is a health and safety hazard, as well. Cracked septic tank lids can further weaken to a point where it will not be able to withstand even moderate weight and end up collapsing. Small children and pets would be in danger to suddenly fall into the tank should the tank lid become compromised like this.

If the damage of your concrete septic tank is far too severe to repair, you might be advised to have your septic tank relocated and get a new drain field installed. Over-saturated soils and an ill-advised septic tank location are valid reasons to have an entirely new septic system installed in a new area in your property.

Signs of Septic Tank Failure

A crack in your septic tank can allow groundwater to seep inside your tank just as it can cause wastewater to leak out into an area other than the drain field. The signs you might notice will depend on the location and size of the crack (or cracks). Note, though, that some of the warning signs of a cracked septic tank may relate to other problems within the septic system. Primary indications of a troubled septic tank include:

Foul odor.  The stench of sewer gases or sewer water can come from a septic tank lid that’s simply out of position or worse, damaged. Gaseous odor can be noticed over a period of days if there is a crack, hole, or deterioration anywhere in the septic tank’s structure. The foul odor will be strongest near the tank location, where the drainfield is, or it may be coming from your neighbor’s tank if it is close enough. Note here that the foul smells may also be coming from your drainfield. Where the smells are strongest would be your typical first clue as to where the damage is, exactly.

Lush vegetation. Lush vegetation is not always a good sign of healthy surroundings. Especially if what you see is just a patch (or patches) of “greener” grass or plants that are different from the rest of your yard. This can be an indication of a leaking septic tank. It is also possible that your system is overflowing somewhere or that a pipe near the septic tank has cracked or come loose.

Extra-soggy yard. If the yard is overly soggy, especially in spots near the septic tank, it is possible that there is leakage. Note here that overly-soggy areas may develop around the tank (due to a clogged tank filter) or drainfield (also due to clogging in the field itself) areas.  

Puddles of standing water. Characteristically, soil tends to compact over time when exposed to wet conditions. If a septic tank has a leak, the water from the leak may cause the surrounding soil to settle and drop down, especially if this area was back-filled loosely after the tank was placed during installation. When the soil around the tank settles and drops down some, it allows surface water from the rains (or sprinkler systems) to puddle or stand.

Backed-up toilets or sinks. Slow draining or flushing can be a warning that the septic tank is damaged. Tree roots may have blocked or damaged the tank’s inlet or outlet lines. It is likewise possible that a baffle may have collapsed or created a blockage and is causing the drainfield to fail. These are possible explanations for sewage back-ups into your home or building.

Remember, though, that foul odor or soggy patches may not be caused by a cracked or damaged (therefore, leaking) septic tank per se. It is possible that the leak is coming from a damaged sewer line or faulty trench. If your toilets and sinks are slow to flush and drain, it helps to video the sewer line first. Before pumping and inspection of the septic tank, some experts recommend having the sewer line coming from the facility to the tank videoed. This will confirm if the line is cracked, clogged, offset or collapsed. In other words, it is ideal to seek the assistance of a septic system professional in accurately diagnosing the source of such warning signs.

A failing septic system is the primary cause of untreated sewage being released and transported to where sewage should never be. Sewage may come to the ground’s surface or to back up into your home or building. Sewage can also find its way into groundwater, surface water, or nearby marine water without us ever seeing it. Untreated sewage carries with it pathogens and other hazardous contaminants. Exposure to which can cause infections among people and animals. It can also cause contamination of water sources and make them unsafe for drinking, swimming, and agricultural uses.

With almost a quarter of US households relying on septic systems, the Environmental Protection Agency has written up policies and regulations that ensure the protection of the environment. Properties situated on or in proximity to wetlands can have an extensive effect on groundwater resources, so it’s crucial that owners of such properties maintain a healthy environmental footprint. Environmental compliance regulations and penalties vary across jurisdictions, so it’s always important to be educated on these and be able to take immediate corrective action when necessary.

The Cost of Repairing a Septic Tank

If you run into a serious problem with your septic tank, of course one of the first things that come to mind might be the cost of repairs. For any type of professional septic tank repair, the national average range in cost is between $850 and $1,500, but this will vary from one state to another.

Repairing a septic tank can be a complex task depending on various factors, with materials and labor being the main elements. If your septic tank was installed on a slope instead of flat land, this likely increases the cost of the overall project. Likewise, if the ground in your area is frozen due to prevailing climates or temperatures. The harder the ground is, the more time, equipment, and expertise will be needed to accomplish the job. In other words, as the repairs become intensive and require more work, like making an excavation in a large ground area, the cost will escalate proportionately.

When problems with your septic tank and/or system arise, it is always best to bring in professionals who are skilled with the repairs that are required. Your trusted septic service provider should be able to provide you with an accurate estimate, project plan, and equipment. This way, everyone’s time and money are efficiently utilized.

The Cost of Replacing a Septic Tank

Now, if your septic tank has developed severe cracks, it might be necessary to install a new tank. In this case, the old tank is decommissioned first. Doing so could involve busting up the concrete and burying it. A steel or fiberglass tank may be crushed and then buried. A new tank is then installed in a different location.

Typically, a standard-sized septic tank is one that can hold 1,000 gallons (or 4,000 liters) of wastewater and the price ranges from $500 to $700. Down the line, the tank type and size you opt for will determine the costs for its installation, inspection, and maintenance. You can expect that the average septic tank to have a lifespan of about 15 years. This is if it’s been maintained adequately and periodically. So yes, you will eventually have to replace your septic tank at some point, whether it be from damage or with age. The cost of replacing your septic tank will depend on the type of system you have installed. The average septic system replacement can range anywhere from $6,000 to $50,000. 

The national average cost for septic tank installation ranges between $3,000 and $9,000. As a reference, the cost to install a typical 1,000-gallon tank, used for a 3-bedroom home, can range anywhere from $2,000 to $5,000, inclusive of the tank cost, which can be anywhere from $600 to $1,000.  Before the actual installation of the septic tank, you are, however, required to secure a permit from your local health department. Permit fees usually amount to around $300.

To be able to determine the cost of installing a septic system, contact your trusted septic professional for consultation and project estimate. Right up there on the top line items in project cost is the septic tank. Below are quick reference guides based on tank size and tank type:

Property Size to Tank Size: A quick guide

Tank Size (in Gallons) Size of House or Establishment Tank Cost
1,000 3 bedrooms $600 to $1,000
1,200 5-6 bedrooms $1,200 to $1,600
2,000 small building (about 14 occupants) $1,800 to $2,300
3,000 large building (>14 occupants) $2,900 to $3,900

Tank Type: A quick guide

Tank Type Cost
Concrete $750 to $2,000
Fiberglass $1,600 to $2,000
Plastic $850 to $1,900

The construction material of the septic tank determines the number and type of installation equipment needed and how much piping is required to connect to and from the tank, your facility, and your drainfield. The minimum septic tank installation charges are somewhere around $2,000 or more.

Life Spans of Septic Tanks

Whether you are in the process of determining what kind of septic tank to install with your septic system or if you are actually repairing your existing septic tank, it’s important to read up on the characteristics of the different kinds of sept tanks available. Each option, or course, will have its unique advantages and disadvantages. Knowing these should be essential in ensuring that you make the best decision when installing, repairing, or replacing your septic tank.

Concrete septic tanks are vulnerable to cracking, corrosion, or even separation. Septic tanks made of concrete are typically quite durable and can last over several decades, but cracks can develop much sooner when low quality concrete mix was used in fabricating the tank, further aggravated by poor system maintenance. The trouble with this is effluent can easily seep out of the concrete septic tank through these cracks. Likewise, groundwater can seep into the tank. Blockage within the tank caused by excess in contents can cause your septic system to back up and cause trouble in your home or building. Concrete septic tanks require regular, periodic inspection and maintenance.

Steel septic tanks. Surprisingly enough, metal septic tanks are the least durable and least popular among all the options. Steel septic tanks are designed to last a maximum of 20 to 25 years. This is because steel septic tanks are susceptible to rust corrosion even before the 25-year lifespan is reached. Similarly, the steel septic tank cover can rust through and deteriorate, posing a serious physical hazard of caving in with even just the moderate weight pressure. If what you have or what you’re considering is a steel septic tank, remember that the steel covers that come with it will have to be replaced periodically. These covers can be replaced without having to replace the whole tank. Steel septic tanks, likewise, require regular and periodic manual inspection and maintenance. Also, you will need to pay close attention to a steel septic tank’s baffles (entry and exit points) as these tend to corrode first.

Plastic or fiberglass septic tanks are primarily water-resistant and thus not susceptible to rust, corrosion, and cracking, unlike its steel and concrete counterparts. Nevertheless, septic tanks made of fiberglass or plastic will have its own weaknesses to watch out for. Low levels of effluent is a possible indication that a plug at the base of the tank has been dislodged. Septic tank plugs need to be inspected regularly even when effluent levels are normal. Make it a point to inspect septic tank plugs during routine pumping or maintenance checks. It may happen, too, that the actual action of pumping may dislodge one or some of the plugs. And plastic or fiberglass septic tanks are more resistant to natural elements and processes within the tank, the lightweight plastic or fiberglass material of construction makes it prone to structural damage. Expertise is required during the installation of plastic or fiberglass tanks to avoid any damages to it. If you opt for a septic tank made of fiberglass or plastic, the ground right above where you intend to bury it should be carefully considered. It is important never drive any vehicles or operate heavy machinery over where the tank is buried. The light material can also cause a plastic septic tank to shift in the ground, especially in wet soil conditions. Also, fiberglass or plastic septic tanks could rise out of the ground, breaking pipes as they move.

The crucial takeaway here is that, regardless of the septic tank make that you decide to go with, you need to periodically have your septic tank inspected and maintained in order to identify potential problems before they escalate to health and physical hazards all around.

Once your septic tank has had cracks, you should have it inspected more frequently than before. Perhaps annually – even when it’s not yet due for the regular pump-out. It goes without saying that sewage leaking onto your property’s grounds can be a real health hazard, with children and pets as the most vulnerable. Your septic tank is the heart of your on-site dedicated sewage treatment system. It takes a well-maintained septic tank to effectively process effluent and safely distribute this to the drainfield.  It is critical to maintaining a septic tank’s pro-biotic environment because beneficial bacteria play a vital role in breaking down the sludge and scum layers. A crack in your septic tank can be the inception of failure of your entire septic system, allowing contaminants to be released to your environment. We surmise that this is NOT the environmental footprint any responsible property owner would want to impart onto their communities.

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