Distributed Sewers are being described by our bureaucracies and agencies as the next generation sewer innovation. However, many questions remain unanswered, and you are urged to be extremely careful about accepting this “sewer” option. Our review of publicly available literature and our own research indicates that distributed sewers are essentially an “advanced” septic system managed by a city or county. The claim being made is that if a utility installs it in your yard, and the utility takes full responsibility for operating it and maintaining it, it is a sewer. Although, this option is still in the pilot program testing phase, it’s low cost and designation as a sewer makes it very attractive to municipalities under a BMAP mandate to convert septic systems to sewer. Distributed batch processing solutions still put nutrients like nitrogen into ground water. They have a drainfield. They have numerous electro-mechanical parts.
The following is a list of concerns and unanswered questions you should be aware of. Use it to help you guide your city and yourself to adopt a proper strategy for your home:
What does it mean when they tell you it works in power outages? Unlike traditional sewers that move waste away from the home, waste treated by these multi-chambered systems stays on your property. An onsite sewer keeps the drainfield in place and uses the drainfield to disperse treated liquid effluent. If you are replacing a conventional septic system because the drainfield has failed, this will add to the cost of the installation. You must still have a drainfield. The claim is that in a power outage, the system will revert to gravity and empty into the drainfield just like a conventional septic system. Since distributed systems rely on power to move waste through chambers to purify waste and remove nutrients, operating any advanced system without power is likely to send untreated mixture of solids and water into the drainfield causing clogging and failure in as little as 48 hours. It is unclear if the utility is financially and functionally responsible for the drainfield and its repair or the homeowner.
Do distributed sewers have the same life expectancy as sewers? All advanced systems wear out at rates faster than sewers or a conventional septic systems. When devices contain electro-mechanical components, the life span is typically 10 years or less, assuming parts continue to be available for maintenance. While cities may receive grants (either Federal or State) to install sewers, the next round of replacements may fall totally on the homeowners. Gravity sewers last the life of the home, they are just a plastic pipe. Conventional septic systems last approximately 20 years. The life span of any other solution is limited by its complexity and the quality of components. There is no data available on the longevity of distributed sewers based on advanced septic systems. Always look for simple solutions.
Who controls your rates? All utilities must request approvals for rate hikes to the Public Service Commission and provide detail on what the rate hike will be used for. This is meant to protect homeowners. In the case of distributed sewer systems, the monthly fee to manage and repair them is often publicized as a fixed low fee, but it is unclear if the Public Service Commission is involved at all. Homeowners must be crystal clear in their understanding of how rates are set, what they cover and what they don’t cover. Utility sewer rates may apply on top of a maintenance fee or replacement parts. Complex devices require constant maintenance and periodic replacement. However, a model for long-term management, technical staffing requirements, and risk assessment has not been developed for large scale, neighborhood-wide installations of these systems. Therefore, costs are not predictable.
If the utility owns the system, who owns the property on which it sits? Traditional sewers are installed on municipal right of ways such as your street or the boulevard between the sidewalks and the street. Everything else is your property. In order to be called a sewer, the utility must be able to provide service on their end on a 24-7 basis. It stands to reason therefore, that a distributed sewer system creates an easement, a takeover of property rights. With that easement comes a loss of personal privacy since service technicians can come on your premises any time; and most importantly, future repairs or replacements can disrupt you anytime. Technicians could be independent subcontractors, not subject to the normal background checks of our counties or cities. This third-party relationship makes the assignments of responsibility much more difficult. Question who will service your unit.
Is there a Wi-Fi or Cellular Phone connection to the utility? Some complex distributed sewer systems rely on a programmable logic controller and the use of either a Wi-Fi or cellular connection to manage the dosing (batch) operation of the system or to trigger a repair call. The homeowner is relieved of the system management burden. That seems like a good idea, at first pass. In today’s connected world, you must keep in mind that every connection to a home network increases the risk of personal intrusion and data security professionals will tell you nothing is secure. We recommend that you insist any manufacturer provide their own cellular connectivity rather than sharing yours. However, cellular connections can be just as unreliable in large major weather events. Cell towers can become overloaded with communications, and you can find yourself losing connectivity with the utility.
The final point: Understand what a change in wastewater management will do to the value of your home or business. Studies show that the wrong choice will lower your property value. Studies show the right choice can maximize your property value. Contact a realtor and ask questions. They can help guide your choices. Since they are called Sewers, your concerns should also consider:
- Whether a system reverting to an unpowered discharge during a power outage is considered a spill and must be reported.
- Are there other EPA and regulatory requirements for sewers that may now apply to your advanced septic system?
- Are you liable for fines? EPA, for example, can issue fines for 1,000 gallons or more of raw or even partially treated sewage into any waterway or aquifer.