All toilets and most showerheads today meet the federal water-efficiency standards, but not all of these products perform satisfactorily. With toilets and showerheads, we include products that meet or exceed WaterSense standards, which includes performance requirements—although we go beyond WaterSense where there are issues not adequately addressed by the program. We also look for other products that conserve potable water, such as rainwater catchment and graywater recovery and reuse systems.
BioBarrier Membrane Bioreactor System
Alternative wastewater disposal systems reduce groundwater pollution by decomposing organic wastes or removing nutrients more effectively. Hand dryers reduce water and paper towel use, alternative treatments for cooling tower water reduce chemical use, and carpet tile allows modular replacement of worn areas. In screening products for this area, we focus on quantifiable environmental benefits and strong performance records.
BioBarrier is a decentralized wastewater treatment system that can process combined household wastewater, including blackwater, into non-potable water clean enough to be reused onsite, even indoors, as part of a graywater reuse system. BioBarrier was the first system to meet the ANSI/NSF Standard 350 for Onsite Residential and Commercial Water Reuse Treatment Systems. BioBarrier consists of a two-compartment septic tank, a membrane bioreactor (MBR), MBR cartridge, a blower, a pump, and controls. The BioBarrier MBR system is certified NSF 350 for its units treating 500, 1,000, and 1,500 gallons per day (gpd). The company offers HSMBR (High-Strength MBR) systems for commercial buildings and small communities that can treat up to 9,000 gpd. Note these units require both blowers and pumps, so energy consumption has to be weighed against the benefits of water reuse and treatment.
The most appropriate wastewater treatment solution will depend on characteristics of the site and effluent. Both centralized (municipal wastewater treatment systems) and onsite systems are used, and there are big differences among products and systems within those categories. Primarily onsite systems are covered here, though some of these may be used in centralized municipal facilities.
A properly designed, installed, and maintained onsite system can do at least as well with nutrient removal as a centralized (municipal) system while providing groundwater recharge. However, conventional onsite wastewater treatment systems—septic tanks and leach fields—typically introduce the nutrients in the wastewater (nitrogen and phosphorous) directly into the groundwater, causing aquifer an surface-water contamination. Failed onsite septic systems are the cause of many water-quality problems.
Various alternative systems provide some nutrient removal, but may cost more up-front, use more energy for pumps and aerators, and have increased maintenance requirements. Some plastic-matrix products incorporate recycled content. A well-designed system will use the least intensive option capable of providing effective treatment and nutrient removal for the site.
For more information the National Onsite Wastewater Recycling Association (NOWRA) and 2002 US EPA Onsite Wastewater Treatment Systems Manual, are good places to turn. The National Environmental Services Center (NESC) staffs a hotline for questions on onsite systems.
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