Water Community Consulting that Delivers Beyond the Ordinary

We are the team you can turn to when you face a critical, unusual, or difficult challenge and may not even know where to start

Our team of engineers, data professionals, economists and communication strategists is dedicated to finding solutions to complex issues for which no well-defined solution may currently exist. We never sell canned answers; we take a scientific approach to developing solutions that meet our clients' unique needs.

Corona's Assistance in the Response to Naegleria fowleri Occurrence in Drinking Water

In 1962 the Center for Disease Control (CDC) began keeping records of human illness caused by the naturally occurring free-living amoeba Naegleria fowleri, which has often been called the brain eating amoeba.  N. foweri received its notoriety due to the rare and often fatal infection of the brain known as primary amoebic menigoencephalitis (PAM).  The majority of PAM cases have been traced to human emersion in natural water bodies, such as lakes or rivers, or from water parks, however in the fall of 2011 the death of a 51-year-old woman and 20-year-old man in Louisiana were linked to PAM caused by the use of tap water in neti pots for sinus irrigation.  Upon further investigation N. fowleri was found in the neti pots and in the plumbing of the homes, which are in two geographically separate parts of the state, DeSoto Parish and St. Bernard Parish. Two years later, in September of 2013, a child in St. Bernard Parish died from PAM, and water from the home also tested positive for N. fowleri. In the fall of 2013, the treated water from DeSoto Parish and St. Bernard Parish tested positive for the parasite. In response to finding N. fowleri in the water systems, the Louisiana Department of Health and Hospitals (LDHH) issued an emergency rule on Nov. 7, 2013 requiring that all water systems in the state maintain a residual disinfectant level of 0.5 mg/L, and increase their number of routine sampling sites by 25%. A 0.5 mg/L level has been shown to control N. fowleri in Australia where it was first identified in drinking water systems in the 1970s.

Corona led the State of Louisiana’s technical response to the N. fowleri deaths from drinking water in 2013, including organizing and facilitating the international science advisory workgroup engaging CDC, USEPA, and academic experts; developing N. fowleri laboratory capacity and methods collaboratively with CDC and other experts; and coordinating the 2-year statewide N. fowleri sampling effort in raw and treated water locations.  Corona also assisted water utilities that experienced and addressed positive N. fowleri detections through sampling plans, regulatory coordination, nitrification control plans, and capital and operational improvements to maintain effective disinfectant residual concentrations.

Dr. Chad Seidel, Corona Environmental Consulting (L); John Williams, District Engineer, Louisiana Department of Health (M); and Dr. Jimmy Guidry, Louisiana State Health Officer (R) at St. Bernard Parish community meeting following positive N. fowleri detection in water distribution system on July 28, 2015.
Louisiana Department of Health Monitoring Plan Portal

EPA Approves Denver Water’s Request for Alternative Treatment Technique for National Primary Drinking Water Lead and Copper Regulations

Corona Environmental Consulting assisted Denver Water in obtaining this first-of-its-kind EPA approved variance by analyzing data, creating models, and performing experimental research that substantiated Denver Water’s approach to achieving Lead and Copper Rule compliance.  Denver Water began implementing the Lead Reduction Program (LRP) in 2020.  The LRP is a lead management strategy that directly addresses the source of the lead with accelerated lead service line replacements, while simultaneously avoiding the long-term watershed impacts of orthophosphate addition.  To address lead concerns while the lead service lines are being replaced, Denver Water is providing filters certified to remove lead to all customers with known or suspected lead service lines.  To address long-term control of lead from other sources, Denver Water is increasing pH and alkalinity.  The Corona team modeled the system-wide lead concentrations of LRP conditions versus orthophosphate (designated as Optimal Corrosion Control Treatment) to demonstrate equivalency between the approaches.  The Equivalency Model will be used in the future to determine regulatory compliance and the success of the LRP.  CEC also assisted Denver Water in experimental design and analysis of their lead pilot rack, coupon testing, and lead filter testing. Additionally, CEC developed a data-driven model to help identify lead service lines in the system and estimate the total number of lead service lines, as well as many other Tech Memos to support the variance.

For more information, visit Denver Water’s LRPP information site.

We are here to help your utility prepare for the Lead and Copper Rule Revision (LCRR)

Drs. Sheldon Masters, Tim Bartrand and Chad Seidel explored implications of the proposed LCRR trigger level in an upcoming Journal American Water Works Association article. We have been given permission by the American Water Works Association (AWWA) to post this article, which will appear in the November edition of the Journal AWWA.

Click on Water Glass to Access Journal Article