Maintenance Contracts

Ongoing maintenance contracts are required for all systems that use secondary treatment.

As the property owner or homeowner, it is your responsibility to have a valid maintenance contract in force at all times.

New aerobic systems come with a two (2) year manufacturer service contract included in the purchase price. At the end of two years you may renew with your current provider or seek another licensed maintenance provider.

Subsequent contracts must be renewed 30 days prior to expiration of the current contract. Failure to hold or renew your contract can result in legal action against the property owner as allowed by law. These are statutory fines that are mandated by state law. A copy of the current contract is required to be on file with the permitting authority.

Maintenance contracts must be provided by a licensed maintenance provider. In addition the maintenance provider must be state registered.

The Fort Bend County Local Order for On-Site Sewage Facilities prohibits property owners/homeowners from performing this task on their own property, unless the property owner/homeowner is a certified maintenance provider for that aerobic treatment unit and holds the required State licenses. Fort Bend County requires a property owner to contract with a certified maintenance provider to perform the required maintenance testing and reporting every 4 months.

The Maintenance Contract shall, at a minimum:

  • List the items that are covered by the contract
  • Specify the time frame in which the maintenance company will visit the property in response to a complaint by the property owner regarding the operation of the system
  • Specify the name of the individual employed by the maintenance company who is certified by the manufacturer of the system
  • Identify the frequency of routine maintenance and the frequency of the required testing and reporting
  • Identify who is responsible for maintaining the disinfection unit

What’s not covered?

In all cases, read your contract thoroughly. Unless identified in your contract, the service provider is not responsible for:

  • Pumping or cleaning tanks
  • Maintaining the disinfection unit
  • Replacing broken spray heads
  • Damage from power failures
  • Homeowner misuse
  • Catastrophes beyond the control of the manufacturer


The maintenance provider is responsible for fulfilling the requirements of the maintenance contract.

At a minimum the maintenance provider shall:

  • Inspect components of the system and note whether or not every component is working during each site visit;
    • If an item is inoperative, the property owner must have the item repaired.
      Note: There may be a cost for the repairs if the item is not covered under warranty.
  • Install a maintenance tag, or some other form of identification, on the system at the beginning of each maintenance contract. This tag shall either be punched or marked at the time of each visit to provide the owner with a record of the visit.
  • Test the system as required for chlorine residual, Biochemical Oxygen Demand, and Total Suspended Solids.
  • Submit a report to the permitting authority and owner at least once every four months. All test results and maintenance reports shall be sent to the permitting authority within 14 days after the test is performed.
  • Respond to owner complaints.

Note: All establishments holding a Fort Bend County Food Establishment Permit and receiving secondary treatment shall be visited and maintained monthly by a certified maintenance provider. A chlorine residual or fecal coliform test shall be made at each site visit where disinfection is required. One BOD and TSS Grab Sample test shall be conducted per year

Annual Maintenance Contract Renewal Fee

  • After expiration of the initial two (2) year maintenance contract, each on-site sewage facility (ATU or other system requiring routine maintenance) must submit a renewing contract with an Annual Maintenance Contract Renewal Fee.
  • Contracts will not be accepted without the renewal fee and must be paid at the time of submittal. Contracts for more than one year {Example: 2+} must pay the annual fee for each year of the contract.
  • The current OSSF permit number must be identified on all contracts.
  • Contracts and fee will not be accepted by fax or mail.
  • There are no credits, refunds or substitutions for this fee. Contracts that are cancelled will require a new contract and another fee to be paid when submitted.
  • Any renewing contract without the fee will be denied and returned.

What to Expect at a Typical Service Visit

The first service visit should be scheduled or arranged between the service provider and homeowner. This visit should include discussing issues, such as:

  • User's manual
  • Manufacturer's recommendations for the unit
  • The system design
  • A walk thorough of your system
  • I information about what to do in case of emergency, any special instructions, issuing keys, etc… For seasonal properties, homeowners will need to know how to shut the system down in the off-season and start it again when needed.
  • Types of disinfecting units used


Wastewater that is sprayed onto the surface must first be disinfected to remove disease causing microorganisms. As the property owner/ homeowner, it is your responsibility to maintain chlorine residual of at least 0.1 mg/l at all times of operation. Failure to maintain a chlorine residual in your system can be a public health hazard and can result in legal action against the property owner as allowed by law.

The most common forms of disinfecting units for aerobic spray are Tablet Chlorination or Liquid Chlorination. If you are unsure of what type of chlorination your system has, ask your installer or service provider.

Liquid Chlorine


  • Chlorine bleach can be purchased in several chlorine concentrations but, it is vital that you use a product that is labeled (registered with the U.S. Environmental Protection Agency) for disinfecting wastewater. Use only non-scented type Chlorine bleach
  • Make sure your chlorinator contains chlorine at all times of operation.
  • If you are unsure about your chlorinator, ask your installer or service provider to demonstrate how to check and refill your chlorinator

Chlorination process


Aerobic Systems Do's and Don'ts

  • Maintain the contract service arrangement offered by the manufacturer after the initial two-year period has expired. It is extremely important that aerobic systems receive regular maintenance. The Law requires it.
  • Monitor and maintain chlorine in your disinfection unit at all times.
  • Call a service professional or your maintenance provider whenever you experience problems with your system, whenever the alarm is activated, or whenever there are any signs of system failure.
  • Use only licensed septic installers to conduct any repairs or modifications of your septic system. Always obtain a permit for any modification, expansion or alteration to your system.
  • Keep detailed records about your aerobic system, including a map of where it is, and general information, such as model name, capacity, state license, date installed, contract service agreement, records of service visits, and maintenance performed. Become familiar with how your own particular system operates, and the way it looks, sounds, and smells when it is working correctly. This way, you may be able to identify problems before they become serious and alert your service provider to anything unusual.
  • Conserve water to avoid overloading the system. Be sure to repair any leaky faucets or toilets.
  • Divert other sources of water, like roof drains, house footing drains, and sump pumps away from the aerobic system.
  • Keep your system accessible for inspections and pumping, yet protected from unauthorized entrance. If access to your system is locked, make sure that your service contractor has a key.


  • Do not tamper with or readjust your systems components.
  • Don't allow anyone to drive over or park on any part of the system.
  • Don't make or allow unauthorized repairs or changes to your aerobic system without obtaining the required permits.
  • Don't use your toilet or kitchen sink as a trash can by pouring harmful chemicals down the drain. Harsh chemicals can kill the beneficial bacteria that treat your wastewater.
  • Don't use a garbage disposal without checking with your local regulatory agency to make sure that your aerobic system can accommodate this additional waste.
  • Don't attempt to clean or perform maintenance on any sealed aerobic unit components.
  • NEVER use swimming pool chlorine in your Aerobic System.
  • Never build a food crop garden in contact with your septic disposal area.

Do Not Flush:

  • Coffee Grounds
  • Kitty Litter
  • Cigarette Butts
  • Dental Floss
  • Sanitary Napkins
  • Condoms
  • Fat, Grease, or Oil
  • Disposable Diapers
  • Tampons
  • Gauze
  • Paper Towels
  • Paints
  • Varnishes
  • Thinners
  • Waste Oils
  • Pesticides
  • Photographic Solutions
  • Bandages

Warning Signs of Aerobic System Problems

  • Alarms or lights going off
  • Any changes in the system's normal operating sound
  • Any changes in the normal color of the wastewater in the aeration on chamber (for example if the color is grayish brown rather than chocolate brown this can sometimes indicate problems)
  • Excessive solids, foam, or scum in the unit
  • Plumbing backups
  • Sewage odors in the house or yard


The maintenance company must be certified to maintain your particular brand of system. (Brand names are usually placed on the control box or inspection lid of your system).A Complimentary List of Certified Maintenance Providers (brand specific) can be mailed, faxed, or obtained at our office. Fort Bend County does not endorse or recommend any individual or company on this list, it is provided only as a courtesy to our citizens.

You can also visit the Texas Commission on Environmental Quality (TCEQ) web site for a list of Certified Maintenance Providers. The web address for the TCEQ is

  • At the top of the page will be DOWNLOAD A LIST OF REGISTERED MAINTENANCE PROVIDERS IN YOUR AREA, select this link

The list of Approved, Registered Providers should appear. There should be a column for Maintenance Company, Maintenance Provider, and Manufacturer. Scroll down to Fort Bend.

Under the Manufacturer column find the BRAND of OSSF that was installed on your property. The company or individual that is Certified by that Manufacturer can provide maintenance on your OSSF.

If the BRAND of OSSF is not listed under Fort Bend County, you can SEARCH surrounding counties.

If any questions should arise while you search for a Maintenance Provider, feel free to call the Environmental Health Department, and we will assist you as best we can.

For more Information on Aerobics:

National Small Flows Clearinghouse (NSFC): The National Small Flows Clearinghouse (NSFC), which specializes in on-site technology, operation, maintenance, regulations, management, finance, and education, has a variety of free and low-cost products available. NSFC can be reached at (800) 624-8301.

NSF International (formerly the National Sanitation Foundation): NSF International is a private, nonprofit organization devoted to research, education, service, and training that tests and publishes standards for products relating to public health and the environment. For more information, you may contact NSF at (800) NSF-MARK.