By Cassie McClure and Suzanne Michaels
There’s no easy way around a simple fact: what goes down our drains does not have the most pleasant smell. It’s a challenge that Las Cruces Utilities (LCU) manages daily at the Jacob Hands Wastewater Treatment Facility (JHWWTF). That’s where 3-billion gallons of the community’s wastewater – flowing from every sink, shower, washing machine, tub, and toilet in our community – is transformed into clear, clean effluent that is released back into the Rio Grande. One of the most effective tools in pulling the smell out of wastewater is a totally natural biofilter, a green and cost-effective system in place at JHWWTF since 2009. LCU uses organic materials recycled from area industries: pecan shells, mulched wood chips, and Class A+ biosolid compost produced at the facility. They work together to “quell the smell.”
“We want to make sure that the nearby community doesn’t work and live in an area with waste smells,” said Lorenzo Martinez, JHWWTF Plant manager. The smell technically is hydrogen sulfide, a gaseous byproduct of wastewater.
The facility has an intricate process to suck up the smells that could hit noses in the area. Raw influent (everything that flows through the City’s sewage lines) arrives at the facility and goes through mechanical bar screens, a grit washer, and a grit remover to remove both large and small debris. Then, biofilters come into play.
Three biofilters of various sizes and depths are located strategically in different areas on the JHWWTF campus. When the wastewater reaches the Equalization Basin, atmospheric gases are removed by large fans and forced through large pipes for underground injection and filtration through the mix of mulch, shells, and compost.
The organic material of the biofilter is filled to the brim with naturally-occurring microorganisms. These microscopic, helpful critters absorb and dissipate the hydrogen sulfide; but they need to be cared for, kind of like houseplants. Here it’s on a very large scale; maintaining a 50 to 60 percent moisture level is critical at all times. And, it’s another green opportunity! The water used to keep the biofilter moist is not fresh water, it’s, JHWWTF’s plant process water. The plant’s treated effluent is used throughout the facility for operation and maintenance purposes.
“In the sewers, the industry standard for controlling odors is by adding chemicals. But at JHWWTF the biofilters absorb smells without chemicals,” explained Martinez. “Here we can work with nature, tend to the biofilters, quell the smells, and in the long run save our customers money.”
You can reach Las Cruces Utilities at 528-3500 from 8 a.m. - 5 p.m. Monday through Friday. Las Cruces Utilities provides GAS – WATER – WASTEWATER – SOLID WASTE services to approximately 100,000 Las Cruces residents and businesses.
PHOTO 1: Plant Manager, Lorenzo Martinez, surveys the reclaimed water sprinklers doing their job keeping moisture at 50% to 60% of biofilter at the JHWWTF.