How much does it cost to replace a septic system?

Septic system replacement or remediation can range from a few thousand to a lot more than a few thousand dollars. Obvious factors include water usage (gallons per day), whether the usage will be steady or intermittent, how many treatment units and septic tanks are required, the destination of the treated effluent (irrigation lines, leachfield, or other), site accessibility, equipment rental, and labor (septic technicians, electricians, private line locators, etc.). Depending on the complexity of the system, a septic design could cost anywhere from a few hundred dollars to a few thousand. It is important to keep in mind that the cheapest bid is just that-cheap-and that there are some things you should seriously reconsider cutting corners on. A healthy percentage of our business is generated from swindlers in the industry who promise customers the world for pennies only to install a system worth exactly that.

What is Onsite Wastewater Treatment?

Cost to replace septic system in Santa Fe: two technicians taking effluent samples from septic tank riser for nitrate testing.

Onsite (or decentralized) wastewater treatment systems are used to treat wastewater from a home or business and return treated wastewater back into the receiving environment.  They are typically referred to as septic systems, because most involve a septic tank for partial treatment.

The most common and traditional septic systems consist of a septic tank that gravity flows to a soil absorption field/leachfield for final treatment and dispersal.  The septic tank allows particulate matter to settle to the bottom of the tank so that large solids do not plug the drain field.  An effluent screen placed in the outlet of the septic tank is used to filter suspended solids out of the effluent.  Final treatment and disposal of the wastewater takes place in the soil adsorption filed.

What is an Advanced Treatment System?

Advanced Treatment means any process of wastewater treatment that removes a greater amount of contaminants than is accomplished through primary treatment.

  • Advanced Treatment may include physical or chemical processes. 
  • Often referred to as:  Advanced Treatment Systems (ATS) or Advanced/Aerobic Treatment Units (ATU’s).
  • ATU’s utilize aeration and manipulation of bacteria in order to biologically treat waste water to higher standards than a conventional primary treatment system

What are secondary and tertiary treatments?

Secondary Treatment means a reduction of the 5-day biochemical oxygen demand (BOD5) and total suspended solids (TSS) concentrations to 30 mg/l and 30 mg/l respectively.

Tertiary Treatment means additional treatment beyond secondary treatment standards, specifically, the reduction in the total nitrogen concentration to levels calculated with the simplified standard loading equation:  Total Nitrogen concentration (in mg/l) = [lot size (in acres) / design flow (in gpd)] x 30,000.

Why do I have an Advanced Treatment Wastewater System?

Two septic tank riser lids.

Advanced Treatment Systems can be used to overcome site limitations that would otherwise prohibit installation of a conventional septic system. Location, space, laws and regulations, soil type, and/or quantity of wastewater being treated limited the ability of a conventional system to properly treat the effluent produced at your location (described above).
Subsequently, they can help to place a system on a smaller lot, a difficult site or you may have one for the purposes of wastewater reuse.

Typical applications of Advanced Treatment Systems include:

  • Small Lots
  • > 500 gpd/acre
  • Shallow Ground Water
  • High Strength Waste
  • Reduction in Setbacks
  • Poor or limited Soil

Section 20 .7.3.605 NMAC provides additional information about the Minimum Required Treatment Levels for Site Conditions.

If this system was elected voluntarily and not required by law (the permit will indicate if this was the case), then perhaps the owner who had it installed simply wished to take advantage of the benefits of effluent re-use landscape irrigation. This would reduce water costs, and allow use to capacity during water restrictions.

Why am I required to have a Maintenance Agreement?

Because ATU’s are more complex, they require a maintenance contract in NM by law for the life of the system and may also require a sampling contract to verify proper functionality. If they are not working properly and treatment is not occurring, then the wastewater could be polluting the watershed. Septic systems are the No. 1 polluter of groundwater in New Mexico!

I am the Buyer/Seller/Real Estate Agent and want to understand why I am required to have a transfer inspection performed by a licensed individual and what the consequences and costs are if the septic system does not pass the inspection.

If you have been maintaining your advanced wastewater treatment system with a licensed provider, it is unlikely that the transfer inspection will yield any big surprises. Water Management Associates, Inc. checks for visible signs of leaks, tank damage, and code violations during regular maintenance. However, sometimes property owners (a hypothetical Seller) have no idea what kind of system is buried in their backyard, let alone that they have been required all along to have had an active maintenance agreement and regular service performed on it! Not only might serious repair be in order, but, according to the same above-referenced regulation, “For advanced treatment systems, at the time of transfer of ownership, the new owner shall submit an amendment of permit updating the ownership change and also provide the department a copy of the valid maintenance and sampling contract in the name of the new owner.” The system will require proof of a maintenance agreement owner moving forward.

NMED Liquid Waste’s webpage delineates the requirements – use this as a check-list!

Do I need to be home when Maintenance is performed on my System?

No. As long as our technicians have access to the system and control panel (are able to turn off electricity running to the system), all work is done outside. Obviously, it is important to secure animals away from the work site, and accommodate for access (it is your responsibility to remove obstructions or hazards from the access points).

Can I maintain the Advanced Wastewater Treatment Unit and System myself?

No. Only an individual who holds both the appropriate licensures and authorization by the manufacturer of the unit to be serviced may perform maintenance. WMA, Inc. is certified to maintain and distribute many brands of advanced wastewater treatment units.

What do I need to do in order to become a licensed Maintenance Provider?

One is required to spend several years as an apprentice under a licensed provider, however, we are always looking for new talent!

Why are these systems so expensive to maintain?

Technician takes sludge measurement of septic tank using dip stick.

Without sufficient understanding of your system, how it enables a work-around in “tough sites” otherwise unable to accommodate septic, and the value of the service, maintenance of an Advanced Wastewater Treatment System can appear costly and unnecessary. It can be especially hard to fork over a few hundred dollars a year when your only frames of reference are conventional septic and city sewer systems.

The most obvious reality is that maintaining septic systems is a risky, laborious, dirty and unpleasant job; we spare no expense when dealing safely with hazardous waste. It is important to us to provide our technicians with the proper tools, equipment, protective outerwear and whatever else will help reduce risk of injury. Equally important is the time and money invested in training our technicians; this is a specialty field, requiring years of experience AND talent before licensure and full mastery can be acquired.

WMA, Inc. technicians generally work in pairs. This allows us to provide you with the added value of two experts, who both have their eyes on your system, and a higher level of efficiency. Our technicians make the work look easy, but it actually takes a lot of field time in order to obtain the level of finesse that translates to not being regularly splashed in the face by or being covered with septic effluent on an hourly basis (you really do NOT want to service your septic system yourself). Senior Partner Ralph Baker Dotson, a envelope pushing innovator in the industry, has spent decades in this business and his invaluable mentorship produces exceptional technicians. The New Mexico Environment Department and the manufacturers of the units hold installers to high standards, and qualification is not taken lightly by them or us.

What happens if I decide not to renew my Maintenance Agreement?

You are required to have a maintenance agreement with a licensed provider for the life of your system. If you decide not to renew your agreement with us, we will notify the Liquid Waste Division of the NMED that we are no longer the R.M.E (Responsible Management Entity)of record for the system.

What are the consequences of not having an active Maintenance Agreement?

You required by law to have an active contract in place. Fines! Shame! Pollution of the environment!

Are you the ONLY providers in the Santa Fe area?

No. Liquid Waste Division of the NMED has a list of licensed providers available upon request.

Are there any advantages in having this type of system?

If you are required to have one, it allows you to have a septic system on your property. They minimize leachfield space, and if reuse irrigation is in place, can cut down on your water bill.

What is an I&M report, and do you have any tools to help me understand it?

An I&M (Inspection & Maintenance) report is required by the NMED as proof of maintenance, as well as to demonstrate the health of your system. As part of our Maintenance Agreement, WMA, Inc. records this data at each maintenance visit, sends you a copy, and submits the original the NMED at the end of the year. We have developed a “How to Read Your I&M” form that can help you to disseminate the data.

Can your company design a re-use system for me that keeps my water bill down and my landscape green?

Yes! We specialize in designing, installing and maintaining for residential and commercial advanced wastewater treatment systems. Modest homes, high-end estates, restaurants, gas stations, and schools represent just some of our customers.

“Onsite Sewage Facilities,” n.d.,
“Liquid Waste Program,” n.d.,