Disinfectant Change In Drinking Water
Change Helps Keep Water Mains Clean
On 9/06/10 the Poughkeepsies’ Water treatment Facility converted our distribution disinfectant from chloramine to free chlorine. This action was taken due to significant corrosion issues causing multiple dirty water complaints that could not be resolved through flushing.
In the unlikely event that the water remains discolored or turbid please contact your local water authority at the numbers listed below:
City of Poughkeepsie, Distribution Operator Jesse Purcell, 451-4111
Town of Poughkeepsie, Distribution Operator Keith Ballard, 462-6535
All other users, Water Treatment Plant Administrator Randy Alstadt, 451-4173 ext. 2003
News Update March 2014
From 2004 through August 2010, chloramines were utilized as the disinfectant to maintain chlorine residual in the distribution system and to minimize disinfectant byproduct formation. Due to unintended consequences and water quality issues in the distribution system with chloramines, the PJWPB decided to return to free chlorine for the distribution system disinfectant in September 2010. With the return to free chlorine disinfection, reduction of chlorinated DBPs at the WTP by the reduction of precursors, such as total organic carbon (TOC), will be required for the PJWB to be in compliance with the Stage 2 DBPR effective October 2013.
In order to determine what additional treatment would be necessary CH2M Hill was contracted to conduct bench scale testing in the summer 2010 (September) and spring of 2011 (May) to assess multiple treatment improvement options, including:
- Enhanced Coagulation with Ferric Chloride, Alum, and Polyaluminum chloride
- Oxidation using chlorine dioxide and ozone
- Organics removal using magnetic ion exchange (MIEX)
These processes were tested alone or in conjunction with one another to assess DBP formation potential at various detention times. Results of that testing, identified that the best solution is to add ozone as an oxidant prior to filtration then followed by biologically activated carbon.
The upgrade will also include upgrading other processes due to age or to increase capacity.
The Upgrade will include the following
- Replace centrifuges, feed pumps, grinder, chemical feed system and sludge trailer
- Add ozone feed system including liquid oxygen storage, ozone contactor and hydrogen peroxide storage and feed system
- Replace filters with sand and granular activated carbon
- Add carbon dioxide storage and feed system for ph reduction
- Cover sedimentation basins
- Add additional polyaluminum chloride storage and feed system
- Replace 4 low lift pumps
Estimated construction cost for this upgrade is $17,250,000. Total project cost including Engineering Services will be $19,500,000.
Construction is scheduled to be substantially completed March 31, 2016.