When it comes to making carpet cleaning greener and more sustainable, cleaning professionals typically think of using environmentally preferable cleaning chemicals and implementing systems that ensure carpets dry quickly, minimizing or eliminating the possibility of mold, mildew, and bacteria growth. However, there is another aspect of carpet cleaning that can also have a big impact on the environment: the wastewater generated by carpet cleaning.
Most of today’s portable extractors used to clean homes and office buildings release approximately 1 to 1.5 gallons of water per minute. Typically, it takes about one hour to clean the carpets in an average-sized home, meaning 90-plus gallons of water are used. If a carpet cleaner services five or six homes a day, that amounts to approximately 500-plus gallons of water per day. Much of that water is disposed of as wastewater.
Carpet cleaning technicians often proudly show the customer how soiled this wastewater is as a way of demonstrating how effective the cleaning has been. But the technician and the customer are often unaware of just how contaminated that wastewater actually is. It often contains the following contaminants:
- Sand, bodily wastes (human and animal), gums, resins, petroleum, and carbon from automotive exhaust
- Highly alkaline chemicals and chemical enzymes (both used in the cleaning process)
- High levels of volatile organic compounds (VOCs)
- Disinfectants (sometimes used in the cleaning process)
- High concentrations of sodium bicarbonate, sodium citrate, sodium phosphate, and/or sodium silicate (often found in carpet cleaning chemicals)
- Dyes, polymers, bleaches, a variety of solvents, esters, and forms of butyl (which dissolve or remove soils and brighten carpets)
In large concentrations, all of these ingredients are potentially toxic. They can be harmful to humans and can negatively affect the lives of insects and aquatic life if they are released into waterways without proper treatment. In some cases, they can even eventually get into the food chain. While many of these ingredients have been removed from green-certified carpet cleaning chemicals, some are still present in reduced amounts.
When we are reminded of just how many millions of gallons of water are used each day for carpet cleaning, the amount of potentially harmful soils and chemicals discharged in wastewater is considerable.
Dealing with Wastewater
Under the umbrella of the Clean Water Act of 1972, federal, state, and local government agencies have created a number of regulations dealing with how to properly dispose of wastewater—including water from carpet cleaning and other industries. These regulations generally forbid releasing wastewater into local waterways, creeks, rivers, or storm sewers. Many also forbid a practice known as “indirect” discharge. This refers to disposing of wastewater on land where it can eventually damage vegetation and soak into groundwater and wetlands.