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Frequently Asked Questions

Septic Systems

What is a septic system?

A septic system—or on-site sewage facility (OFFS)—is a method of dealing with household wastewater in areas where city sewer is not available. There are many types of OSSFs. Most people use the term “septic system” very generally, which may include all types of on-site sewage facilities. A typical standard septic system consists of a septic tank (to separate the solids from the liquids) and an absorption area where the liquids are treated in the soil before returning to the groundwater supply. Learn more about common septic system types, or watch a septic system animation.

How does my septic system work?

Download a free copy of Understanding and Maintaining Your Septic System to learn how your system works and how to keep it functioning properly. You can also use this interactive septic system animation.

What exactly is a septic tank?

It is a “watertight” container, usually made of concrete and buried somewhere in your yard. The septic tank separates the solids from the liquids. Most of the solids settle in the tank and will need to be removed periodically by hiring a licensed professional to clean the tank. Newer tanks contain a dividing wall, which separates the tank into two compartments. All tanks should have an inlet baffle and outlet baffle to keep the scum and sludge inside the tank. Learn more about standard septic systems.

How do I know what size my tank is?

Septic tanks are sold in a variety of shapes and sizes. The size of tank depends on the number of bedrooms in the home and the square footage of the home. If you do not have accurate records from the installation, we can give you a good estimate of the size over the phone, or measure your tank.

Are all septic tanks the same material?

No. Most septic tanks in the area are made of concrete, but there are some that are made of fiberglass and plastic. Some older tanks may be made of metal.

Why is the interior of my concrete septic tank deteriorating?

Deterioration of the concrete septic tank is typically caused by hydrogen sulfide gas. Most deterioration issues are associated with heavy garbage disposal usage as the rotting food creates hydrogen sulfide. Also, backwash from some water softeners into the septic tank using salt for water treatment can also create hydrogen sulfide. Since it is a gas, the deterioration occurs above the water line in the tank.

Do’s and Don’ts for Septic Systems

DON’T treat the system as city sewer. Economy in the use of water helps prevent overloading of a septic system. Overloading the system could shorten the life of the system and necessitate expensive repairs. Leaky faucets, running commodes and malfunctioning water softeners should be carefully guarded against. Avoid doing all your laundry in one day; surges of water entering the system may hydraulically overload the system and throw off the balance of bacteria.

DON’T flush anything except toilet paper and wastewater. Things that may harm your system include: excessive use of a garbage disposal, grease, too many cleaners, soaps, bleaches, detergents drain cleaners, fabric softener, cigarette butts, diapers, wipes, feminine products, condoms, q-tips, paints, paint thinners, auto grease, antifreeze, unused medicine, automatic toilet cleaners, hair combings, coffee grounds, dental floss, disposable diapers, kitty litter, gauze bandages, paper towels, etc.

DO pump and clean your tank on a regular basis by a registered and licensed septic tank service company and dispose in a manner approved by TCEQ.

DO maintain the area where the septic tank and drainfield are located. For a period of time after installation, the soils will settle. Filling and leveling of the area should be maintained so that rain and surface water will not enter the drainfield and cause flooding. Use good soils for leveling. Grass cover is required over the area of the drainfield and around spray areas for aerobic systems. Keep the vegetation short over the drainfield and around the spray heads. If you have an automatic yard sprinkler, set it for shorter periods of time so that you don’t flood the drainfield or spray area by over watering.

DON’T build any structure over any portion of the system. The structure will prevent access to the system for maintenance, reduce the ability of water to evaporate from the soil and restrict air movement into the soil.

DON’T plant landscaping around the system. Keep vegetation mowed or trimmed around all system components.

DON’T drive heavy equipment over the components of the system. Heavy equipment can crush the components and lead to expensive repairs.

DON’T use additives. Some additives may even harm the system’s operation by liquefying the sludge in the tank and carrying it out into the drainfield, causing system failure. Natural bacteria are present in the wastewater to decompose the waste.

My system is backed up. Do I call a septic company or a plumber?

Although plumbers and septic maintenance providers may seem to deal with the same problems, the truth is these two businesses do not overlap; a plumber does not have the knowledge required to fix septic systems, and we are not equipped to resolve plumbing issues. If you’re experiencing a backup, there are a couple things you can check to help you decide if you need a plumber or a septic maintenance provider:

Septic Tank Cleaning

Why should I have my septic tank cleaned?

Cleaning your septic tank is the key to the life of your septic system. The purpose of the septic tank is to separate the wastewater from the solid waste and allow only the wastewater to enter the soil absorption field. The less frequently the tank is cleaned, the more solids are likely to enter the soil absorption field. When this occurs, your soils and drainfield will clog and lead to system failure. In most instances, the entire system will have to be brought up to current regulations set by the Texas Commission on Environmental Quality (TCEQ) and your local permitting authority, which usually requires an entirely new system.

How often should I pump out my septic tank?

A conventional septic tank should be pumped every 3 to 5 years, depending on the size of the tank and the household wastewater usage. For example: a family of 6 on a 1000-gallon tank will need to pump out the tank more frequently than a family of 3 on a 1000-gallon tank. In Bexar County, the tank is required to be pumped/cleaned at least every five years in order to renew the License to Operate for the system.

Diagram - How often should I have my septic tank pumped?

How do you find the tank?

The tank is usually constructed out of concrete, so we first use a probe and/or a metal detector. If finding the tank is difficult by these methods, an electronic locator can be used at an extra charge. This electronic locator is able to locate the general area of the tank (as long as there is not a blockage from the house plumbing to the tank) if the tank may be close to or under a deck, patio, pool patio, room addition, or if the tank is constructed of plastic. The homeowner may also contact the county to obtain records on the system, which usually includes a layout, although not all layouts are accurate.

Will you have to tear up my yard to find or pump the tank?

No. We use shovels to expose the tank lids. If you have nice grass, we will be careful to place the grass back in a way that it will easily grow with regular watering. If the tank is difficult to find, several holes may be dug. In extreme cases, an excavator may be used to locate or expose the tank and the lids, with your approval.

What can I do to prevent having to dig the next time my tank is pumped?

Risers can be installed on most septic tanks. The riser brings the lid up to the surface of the ground (or can be installed just below the ground or above the ground, depending on your preference).

Will the vacuum truck ruin my lawn?

Our trucks carry 150 feet of hose so that we can easily reach the tank from your driveway or the street. We can bring more hose to your site if requested in advance.

How much will it cost to clean my tank?

It depends on the size of your tank and the amount of gallons collected. Most companies charge by the number of gallons collected due to the cost charge by the treatment plant where the waste is transported to. Other factors may include difficulty locating the tank or lids, the thickness of the sludge, pumping uphill, etc.

Can you pump the tank through the cleanout?

No. Even if a hose could fit down the cleanout, this still would not provide a thorough cleaning. The tank should be pumped from the actual access lid(s) on the tank, which are usually buried 6-12 inches below the surface of the ground. Depending on the age of your system, the tank may have a dividing wall, in which case we will need to gain access to both compartments to thoroughly clean the tank.

Do they pump everything out of the tank?

Some liquids will remain on the bottom of the tank, simply because it is impossible to leave the tank completely dry. Bacteria will remain in liquids and help the supply of bacteria increase as you use the system.

How will I know if my tank is full?

The question should be “How do I know how much sludge is in my tank?” The liquid level in your tank should always be at its normal level, which is at the outlet pipe (unless you are having a backup from the absorption area). So, lets say you have a 1000-gallon tank. The tank will be filled to 1000-gallons, at the level of the outlet pipe. When your tank is cleaned it will be empty. Once you use 1000-gallons (or however many gallons your tank holds to the outlet pipe), the tank will be filled to its normal level. The amount of sludge in the tank then determines when the tank is pumped, not when it is “full.”

My tank was just pumped and now it’s full again. Why?

If you originally pumped the tank because the tank was overfull (meaning the liquid level in the tank is higher than normal, or “backed up”) and it is overfull again, this is sign that your absorption area is not accepting your household usage of wastewater. Lets say you have a 1000-gallon tank. The tank normal liquid level in the tank would be 1000-gallons at the level of the outlet pipe. When your tank is cleaned, the tank will then be empty. Once you use 1000-gallons by flushing the commode, taking showers, doing dishes or laundry, the tank will again be filled to its normal level (typically, this may only take a few days to one week). If you find that the tank is overfull again, this indicates that your absorption area is not accepting your wastewater. Check for dripping faucets, running commodes and malfunctioning water softeners as they could cause the absorption area to flood out. If you find there are none of these, more investigation may be needed to discover the cause of system failure and find a remedy.

Questions to ask when hiring a professional to clean your septic tank

  • Does the company carry general liability insurance?
  • Does the company carry workers compensation insurance?
  • Is the company registered with the TCEQ and SAWS for hauling wastewater?
  • How long has the company been in business and cleaning tanks?
  • What methods are used to locate the tank?
  • Does the price include finding the tank and exposing the lid(s)? Most tanks installed after 1989 will have two lids that require digging to properly clean both compartments of the tank.
  • Does the price include dumping fees?
  • Does the price include any additional time on site due to locating the tank or a tank with very heavy sludge?
  • Are their hoses long enough to reach the tank without driving over your lawn?
  • Do they carry extra lids on the truck in case yours breaks?
  • Do they check the inside of the tank for baffles, walls, cracks, leaks, roots, etc.?
  • Do they pump the tank though the tank lid(s) or the cleanout? Proper cleaning can only be accomplished through the tank lid(s)? • Do they wash out the tank after it is pumped?
  • Will they remind you the next time your tank should be cleaned?
  • Do you have to be there when they clean the tank?
  • Do they accept credit cards?

Installation & Repairs

What determines the type of system you can install?

There are many factors. Most important is the type of soil on your particular property. Slope, restrictive horizons and minimum setback requirements are other factors that are involved. Learn more about common system types here.

Questions to ask when hiring an installer for a new system or repairs

  • Does the company carry general liability insurance?
  • Does the company carry workers compensation insurance?
  • What types of systems do they install?
  • Which aerobic brands to they install?
  • Is there any warranty with the installation? If so, who warranties the system? The designer or the installer?
  • Will the company provide an orientation to go over the system after it is installed?
  • How long has the company been installing the type of system your property requires?
  • How long has the company been in business?
  • Does the installation/repair price include design and permit fees?
  • Will the company obtain required permits prior to installation or repair?
  • Does the installer hold a valid installer license by the TCEQ specifically for your system?
  • Is the installer knowledgeable of the local regulations for your county or entity?
  • Is the company qualified to service the system after installation?

Additives

Should I use additives?

No, additives are not necessary and are not recommended by the TCEQ or EPA. Some additives may even harm the system’s operation by liquefying the sludge in the tank and carrying it out into the drainfield, causing system failure. Natural bacteria are present in the wastewater to decompose the waste.

UMN Additives Fact Sheet

Additive information from the University of Minnesota.

Common System Types

What is an OSSF (On-Site Sewage Facility)?

An On-Site Sewage Facilities (OSSFs, or more commonly “septic systems”) are underground systems used to capture and treat wastewater. OSSFs are most common in rural areas where city sewage systems do not reach.

There are many types of OSSFs, but the three most common are standard septic systems, aerobic systems, and low-pressure dosing systems. Learn more about common septic system types or see an animation of a septic system in action.

What is a Standard Septic System?

A standard wastewater system with soil absorption system is the most cost efficient and common method available to treat residential wastewater. Download a free copy of Understanding and Maintaining Your Septic System.

What is an Aerobic System with Spray Irrigation?

Aerobic units treat wastewater using a scaled-down version of the process used by municipal wastewater treatment systems. They treat wastewater well enough to be used in conjunction with spray systems, which distribute treated wastewater over lawns. Download a free copy of Living with an Aerobic Treatment Unit and Spray Field.

What is an Aerobic System with Drip Irrigation?

A subsurface drip system distributes wastewater to the lawn through a system of tubing installed below the ground surface. Read about the four main components of an Aerobic System with Drip Irrigation.

What is a Low Pressure Dosing System?

A low-pressure dosing system (LPD) treats wastewater then pumps it into the soil several times daily. Of the nonstandard drain fields, it is the least expensive to install and operate. Read about the advantages and disadvantages of a Low Pressure Dosing System.

Aerobic Systems

How does my aerobic system work?

Download a free copy of Living with an Aerobic Treatment Unit and Spray Field to learn more about how aerobic systems work. You can also view this interactive septic system animation.

Why should my aerobic system be checked every four months?

To keep your system functioning properly, regular maintenance is required. If your system isn’t functioning properly, it may create a health hazard. All aerobic systems, no matter how perfectly designed, installed, used, and maintained, will have parts that will need to be replaced. Some are less expensive like diffusers, filters, etc. Some are more expensive items like the pumps, removing the sludge from the tanks, etc. Any aerobic system owner should expect to have parts replaced on their system, just as any vehicle owner should expect to change the oil, replace the tires, and eventually experience more costly repairs. Life cycles to each part of the system will depend how many people are using your system, how much water you use, what items you eat, medicines you may take, chemicals/cleaning products, what you flush down the commode (example: feminine products, condoms, baby wipes, etc.) and regular life cycles for each part, etc.

Some of the items we check during your regularly scheduled maintenance check will need to be repaired or replaced according to their life cycle. These items include (but are not limited to): aerator, aerator filters, filter pad, diffusers, irrigation pump, audio alarm, visual alarm, timer, control panel, electrical circuits, chlorine supply, spray heads, photocell, floats, diaphragm/veins, wires, junction box, lids, and sludge level from the tank(s).

What do I do if my alarm is on?

Don’t panic! It is usually not an emergency. Press the silence button to silence the buzzer. Check the breakers to your system; sometimes short power outages can cause the alarm to activate. If the light stays on or if the buzzer sounds again, call your maintenance provider as soon as possible. Never turn the system off.

Can I use swimming pool chlorine tabs for my aerobic system?

No! Only use calcium hypochlorite tabs that are for the specific use of treating wastewater. You can buy buckets of tablets from our office, Home Depot or Lowe’s. If you are using swimming pool chlorine, make sure you clean out out the chlorinator before adding calcium hypochlorite tabs. Mixing the two different types of chlorine could cause an explosion.

Can I move my spray heads or add more?

Possibly, but any alteration in the spray area may require a repair permit. The system is designed to be installed in specific areas and to spray a specific amount of square footage in order to meet TCEQ and local requirements. Adding spray heads or moving spray heads may not be feasible to meet those requirements. Any alteration of the system by the homeowner, landscaper, or irrigation company will put the system out of compliance and will be at the homeowner’s expense to bring the system back into compliance.

Do’s and Don’ts for Aerobic Systems

DON’T treat the system as city sewer. Economy in the use of water helps prevent overloading of a septic system. Overloading the system could shorten the life of the system and necessitate expensive repairs. Leaky faucets, running commodes and malfunctioning water softeners should be carefully guarded against. Avoid doing all your laundry in one day; surges of water entering the system may hydraulically overload the system and throw off the balance of bacteria.

DON’T flush anything except toilet paper and wastewater. Things that may harm your system include: excessive use of a garbage disposal, grease, too many cleaners, soaps, bleaches, detergents drain cleaners, fabric softener, cigarette butts, diapers, wipes, feminine products, condoms, q-tips, paints, paint thinners, auto grease, antifreeze, unused medicine, automatic toilet cleaners, hair combings, coffee grounds, dental floss, disposable diapers, kitty litter, gauze bandages, paper towels, etc.

DO pump and clean your tank on a regular basis by a registered and licensed septic tank service company and dispose in a manner approved by TCEQ.

DO maintain the area where the septic tank and drainfield are located. For a period of time after installation, the soils will settle. Filling and leveling of the area should be maintained so that rain and surface water will not enter the drainfield and cause flooding. Use good soils for leveling. Grass cover is required over the area of the drainfield and around spray areas for aerobic systems. Keep the vegetation short over the drainfield and around the spray heads. If you have an automatic yard sprinkler, set it for shorter periods of time so that you don’t flood the drainfield or spray area by over watering.

DO check your chlorine once a week to once a month.

DON’T build any structure over any portion of the system. The structure will prevent access to the system for maintenance, reduce the ability of water to evaporate from the soil and restrict air movement into the soil.

DON’T plant landscaping around the system. Keep vegetation mowed or trimmed around all system components.

DON’T drive heavy equipment over the components of the system. Heavy equipment can crush the components and lead to expensive repairs.

DON’T use additives. Some additives may even harm the system’s operation by liquefying the sludge in the tank and carrying it out into the drainfield, causing system failure. Natural bacteria are present in the wastewater to decompose the waste.

How do I unclog my tablet chlorinator?

Using tablets in your aerobic system is critical to its efficient wastewater treatment, but the tabs can become mushy and clog the chlorinator. Fortunately unclogging it is simple:

Inspections

Questions to ask when hiring an inspector for real-estate transactions

  • Is the inspector certified by the National Association of Wastewater Transporters (NAWT)?
  • Does the inspector hold a valid Texas Commission on Environmental Quality (TCEQ) license to install the type of system they are inspecting?
  • Is the inspector knowledgeable about the type of system they are inspecting?
  • Is the inspector knowledgeable of local real-estate inspection requirements for each county and entity?
  • What are the inspection procedures?
  • Does the inspector have different procedures for different types of systems?
  • How does the inspector locate the tank?
  • Does the inspector look inside the tank or pump the tank during the inspection?
  • Does the inspector obtain the records on the system prior to the inspection and provide the records with the report?
  • Will the inspection report be acceptable for your mortgage company?
  • How long has the inspector been in business?
  • What experience does the inspector have with the type of system that is to be inspected?
  • If repairs are recommended, is the inspector knowledgeable about repair requirements in each local area?
  • Will the inspector be able to provide an estimate if repairs are recommended?

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Licensed by the Texas Commission of Envirotnmental Quality (TCEQ)
Certified by the National Association of Wastewater Transporters (NAWT)