Water treatment plant improvements

The facility is a 20 million gallons a day (76Ml/d) conventional filtration plant, including: a raw water pumping station and intake on the Susquehanna River; chemical feed building housing alum, chlorine dioxide, sodium chlorite, powder-activated carbon, acid, caustic and polymer; four flocculation/sedimentation basins; and 10 rapid sand filters, chlorination, corrosion control and fluoridation.

The site contains separate office and maintenance facilities for water treatment and water distribution, and sewer collection operations for the City.

The improvement program provided upgrades to the treatment plant to comply with current and proposed drinking water regulations to improve the reliability of the process, and to address the rehabilitation needs of a 40-year-old facility.

The project also included major upgrade and expansion of the office/maintenance space and Information Technology improvements to link the communication and maintenance between common staff across two City departments, including a water and sewer system-wide SCADA system. Other plant improvements are listed below.

• Chemical feed systems replacement
• Conversion from chlorine gas to sodium hypochlorite
• A silo for powder-activated carbon storage and feed
• Exterior masonry and roof replacement of all buildings
• Expansion of residuals pumping capacity
• HVAC replacement for all buildings
• Structural improvements to process tanks
• Replacement of major electrical components
• Replacement of raw, finished water and backwash pumping systems

GHD's services included: evaluation, design, bidding, construction engineering, permitting, bench-scale treatment studies, SCADA and PLC programming, computerised maintenance management, and computerised operations and maintenance manuals.  A detailed construction sequence was developed and communicated to the contractor to allow continuous production during the upgrade even while major process systems were being interrupted. The upgrade was completed without impact to the city's supply needs and met all water quality standards.

The water plant improvements provided USD15.5 million in upgrades and the project is the largest single public works project undertaken by the City. The project benefits include: a considerable reduction in power consumption due to higher-efficiency pumping equipment and the availability of distribution system storage information through SCADA to time pumping for off-peak electrical demand periods; a reduction in chemical costs due to online analyzer control and flow pacing; and, a significant improvement in process reliability. In fact, the plant was able to maintain production and meet all drinking water quality standards during the worst flood of record on the Susquehanna River.

The project, funded through the New York State Revolving Loan Fund, received the Environmental Project of The Year Award from the New York State American Public Works Association.