Septic Tech for “Unbuildable” Lots

New septic technology could help reduce pollution, save water, and qualify homes for LEED points. It could also let you build on otherwise unbuildable lots.

Dave Hopper has been in the septic installation business since the late 1980s and rarely sees anything new that qualifies as a game-changer.  That was until last year when his company, H&M Construction in Walton, Ky., was asked to install a new type of system from Cincinnati-based NextGen Septic. He has since installed about a dozen of these systems and now offers them to builder customers where the project warrants.

Although his customers end up paying an installed cost about twice that of a conventional septic, none of them complain because it lets them build on lots they could not build on otherwise.  “The system basically sells itself,” he says.

Problem Solver

The NextGen system consists of a stainless-steel treatment unit placed on top of a two-chamber septic tank.  The unit is small enough to fit between the tank’s two risers.

Rather than flowing to a leach field, effluent from the septic tank is pumped through the NextGen unit, where biomedia remove nitrogen, phosphorus, viruses, bacteria and other organic contaminants.  Hopper says the unit’s output is clean enough to be discharged into the environment or for use in landscape watering.  “It’s cleaner than any system we have ever seen,” he says.

In fact, NextGen claims that the unit’s output exceeds the standards used for wastewater treatment plants.  It removes up to 99% of nitrogen and phosphorous from the effluent, the main causes of algae blooms and other water pollution issues.

It also eliminates the need for a leach field.  “That makes it a great solution for a lot with poor soil conditions, as well as one that’s too small for a leach field or whose topography won’t accommodate one,” says Hopper.

Hopper isn’t the only contractor who sees these advantages.  NextGen president and inventor Rakesh Govind, who is also a professor of chemical engineering at the University of Cincinnati, says that it has been installed in 37 homes since earning state certification from Kentucky and Ohio.

Water Saver

Govind believes that decentralized treatment technologies like his make a lot more sense from an environmental standpoint than even the most effective municipal treatment plants.  That’s because the output from most municipal plants ends up in the ocean, which does nothing to replenish local groundwater.  “This has led to declining ground water levels worldwide,” he points out.

But despite the case this makes for local water recycling, current on-site technologies often do more harm than good.  For instance, conventional leach fields clog over time, sending pollutants into aquifers, lakes and estuaries.  “There are more than two million failed leach fields in the U.S.,” says Govind.  “I’ve seen ponds in subdivisions with algae blooms created by this discharge.”

The technology also has water conservation potential.  The discharge is clean enough to be pumped to a graywater plumbing loop for use in flushing toilets and watering lawns, two of the biggest water loads in a typical home.  (Toilets alone account for 40% of most homes’ water use.)  That would make it less environmentally damaging to build in places where water is scarce, like the desert Southwest.  The reduction in water use can also help earn the home LEED points.

The system has two pumps that obviously use electricity, but combining it with a solar panel will ensure that treatment continues even during power outages.

At this point, the NextGen system requires state-by-state approval as an alternative septic.  However, it’s undergoing tests at a National Sanitation Foundation lab, a process that takes about six months.  Govind expects to earn certification by September, which would make it a recognized system in most of the country.

This article was reprinted with permission from The Energy & Environmental Building Alliance (EEBA). To read more articles like this, check out the EEBA blog here.