Why the Change? 

The Hannibal Board of Public Works has been in violation of federal drinking water standards since 2012, and has been sending public notices to customers quarterly since the violation began.  The violation is related to disinfection byproducts (DBPs). 

In 2011, the HBPW hired a consultant to put together a list of options for us to choose that would meet the new federal standards.  Of these options, the HBPW Board approved the use of Chloramines as the new water disinfection procedure, and construction began at the Water Treatment Plant in early 2015. 

Letters were sent to our larger industrial users prior to the conversion, and mail inserts were sent to all HBPW water users. 

The HBPW Water Treatment Plant is currently undergoing several improvements.  Check out the Hannibal Board of Public Works Facebook or YouTube pages for pictures and video of the construction process! 


What Are Chloramines? 

Chloramines are a mixture of chlorine and a small amount of ammonia.  While obviously toxic at high levels, neither poses health concerns to humans at the levels used for drinking water disinfection.  Click HERE for additional information regarding Chloramines. 

There are some within the community that have shown concern with the use of Chloramines for water disinfection.  From the extensive research the HBPW and it's hired consultants have done, as well as the research done by the United States Environmental Protection Agency, the HBPW agreed that the use of chloramines was the best option for disinfection.  The use of Chloramines has become one of the most common forms of water disinfection in the United States.  Chloramines, the monochloramine form in particular, has been used as a disinfectant since the 1930's. 

Because the chloramine residual is more stable and lasts longer than free chlorine, it provides better protection against backerial regrowth in systems with large storage tanks or piping systems, buildings taller than 10 stories, and dead-end water mains.  One case study done by the National Center for Infectious Diseases stated that, "Increasing use of monochloramine in water supplies throughout the United States may reduce Legionella transmission and incidence of Legionnaires' disease" (Read the full article HERE, or visit www.cdc.gov/eid). 

In 2000, the American Water Works Association published a similiar journal article that studied hospitals where outbreaks of Legionnaires' disease occured.  They found that hopsitals supplied with drinking water containing free chlorine were 10.2x more likely to have reported an outbreak of Legionnaires' disease than hospitals that used water with monochloramines.  Read the full article HERE

Additional Information

Press Release send August 28, 2015

Letter from HBPW Director of Operations

Letter to the Editor - Hannibal Courier Post sent November 16, 2015

MoDNR Response Letter sent November 23, 2015

GAC Memo presented to HBPW Board February 16, 2016


April 5, 2017

On April 4, 2017, the citizens of Hannibal voted to remove the use of ammonia as part of the city’s disinfection system by a vote of 1,259 to 894.  The proposition called for the Hannibal Code of Ordinances to be amended to include the ordinance prohibiting the use of ammonia in the public drinking water system within 90 days of approval by City Council. 

The HBPW Board has solicited a proposal from Black & Veatch Engineers to begin the process of studies, reports, and designs required to eliminate the use of ammonia in our drinking water.   The proposal is currently being written. 

April 19, 2017

The HBPW Board solicited a proposal from Black & Veatch Engineers to begin the process of studies, reports, and designs required to eliminate the use of ammonia in the drinking water.  This is the Board’s first action item required to come into compliance with the results of the Proposition 1 referendum on April 4, 2017.  During the April 18th board meeting, the HBPW Board received the first draft proposal from Black & Veatch.  The Board will review the proposal and convene next month for a special board meeting to discuss changes. 

Read the memo from Bob Stevenson to the HBPW Board HERE. 

May 9, 2017

The HBPW Board held a special meeting on Monday, May 8, 2017 to discuss and approve the Chloramine Replacement Alternative Evaluation proposal submitted by Black & Veatch Engineers.  Several changes were made to the first draft proposal given to the HBPW Board members last month, and the final document was approved. Read the approved proposal HERE

Part of B&V's scope of work will help identify target treatment goals for the 90 day referendum period, as well as long term target goals and objectives for the project, while remaining compliant to all regulatory requirements.  It is the HBPW's responsibility to remain compliant with both the City referendum and current drinking water standards throughout the entirety of the project.