New nutrient removal research presented at microbiology conference

28 May 2013

The American Society of Microbiology’s 113th general meeting was held on May 18-21 in Denver, Colo., showcasing the research of leading microbiologists from around the globe.

Researching nutrient removal in a study called the "Molecular Gene Probe" method, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) featured Dr. Geeta Rijal, MWRD supervising environmental microbiologist, who presented her research of the dynamics of ammonia oxidizing bacteria and nitrite oxidizing bacteria, which play an important role in the removal of nitrogen from the wastewater treatment process.

"There are nutrient-removing bacteria naturally growing in our wastewater system," said Dr. Rijal. "With a proper molecular identification method, we can help to evaluate their abundance and nutrient removal potential."

Water quality is being impaired all over the world due to excessive nutrients from agricultural runoff and wastewater. Nitrogen and phosphorus cause algae blooms, which in turn deplete oxygen in the water and make the water environment inhospitable for aquatic life. The Gulf of Mexico suffers from a "dead zone" due to low oxygen, also known as hypoxia, at the mouth of the Mississippi River.

Nationwide, regulations are starting to strengthen with regards to nutrient limits; as a result, Illinois water utilities are facing billions in costs to meet increasing demands to enhance treatment processes, improve infrastructure, and address sewer overflows. The estimated cost for all Illinois plants to implement Phosphorus removal ranges between $570 million to almost $3 billion.

In April, the American Academy of Environmental Engineers (AAEE) and Scientists Certification Board nominated Dr. Rijal as the Board Certified Environmental Scientist in the Environmental Microbiology Specialty. Dr. Rijal was invited to attend the Excellence in Environmental Engineering and Science Conference at the National Press Club in Washington, D.C., on April 25 and received the recognition from the past AAEE President, Dr. Cecil Lue-Hing, former MWRD Director of Monitoring and Research. Nancy Helen Sutley, who leads the White House Council on Environmental Quality, served as the conference’s keynote speaker.

"The issue of the Gulf hypoxia is a national concern," said Commissioner Patrick D. Thompson, chairman of the MWRD Monitoring and Research Committee. "I commend Dr. Rijal and her colleagues at the MWRD for their research efforts in developing a potential solution that will have long-term benefits."