Opportunity
Located between East Newark and Jersey City, the town of Kearny is named after the Civil War general Phil Kearny. General Winfield Scott, Kearny’s commanding officer, called him "the bravest man I ever knew.”
The Kearny Municipal Utilities Authority, created in 1988, is responsible for the collection of wastewater and stormwater from portions of the Meadowlands and from the South Kearny section of the town. South Kearny, sometimes called Kearny Point, occupies a peninsula formed by the Hackensack and Passaic Rivers. Once described as “a maze of warehouses, truck depots, distribution centers, train tracks and power lines,” it is accessible from an off ramp that allows drivers to exit from the middle of the Pulaski Skyway.
The South Kearny Pump Station, with a capacity of 17.5 million gallons per day (MGD), accepts combined sanitary and stormwater flow. Much of the equipment had reached the end of its useful life (15 to 20 years). Increasing stormwater flows also exceeded the facility’s capacity during extreme weather events. The pump station’s wet well routinely surcharged during high-flow events, causing increased maintenance.
The pump station did not have a functional grit removal system, which led to grit deposits at the treatment plant. As a result, the existing parshall flume used for metering flows to the Passaic Valley Sewerage Commission (PVSC) was inaccurate, impacting the calculation of service charges.
Solution
In 2004, the KMUA retained Mott MacDonald as prime consultant to provide engineering services for the rehabilitation of the Kearny Point Pump Station. The proposed work included restoring the building structure and the process equipment to a fully functional and efficient operation.
As prime consultant, Mott MacDonald provided design for process, structural, architectural, electrical, instrumentation, and HVAC services. We provided shop drawing review, onsite observation, and overall construction administration.
Our design team modified the existing wet-well channels to accommodate redundant chain and flight grit removal equipment, grit sumps, grit pumps, and motorized sluice and slide gates with controls to regulate flow into the pump station and individual channels.
A new 18-inch parshall flume was installed so that the full range of flows could be measured accurately. A temporary bypass pumping system with flow metering was designed to allow the construction of the new facilities.
A new pile-supported masonry building with odor control equipment was constructed to enclose an existing traveling-rake bar screen. Based on evaluations of remaining useful life, the existing dry-pit submersible pumps and standby generator were retained and integrated with the modified facility.
Outcome
Safety
No accidents or injuries were experienced during project construction. During design development, Mott MacDonald worked with KMUA’s operations staff to identify measures to improve safety during routine maintenance.
New monorail systems with electric hoists were installed, allowing operators to remove equipment and pumps from a dry well three stories below grade without the need for temporary rigging. A mechanical bar screen formerly located outdoors was enclosed, prevented the formation of ice that creates dangerous operating conditions for workers who remove screenings on a daily basis.
Quality
The upgraded facility has operated reliably since 2007, in contrast to a past history of frequent downtime for equipment maintenance and frequent wet-well flooding. Accurate flow metering was achieved, a major concern of the receiving wastewater treatment plant.
Mott MacDonald's design for the rehabilitation of the Kearny Point grit removal system restored the pump station’s pretreatment capability, allowing the owner to avoid penalties from the receiving treatment plant. New electrical service and distribution equipment increased the reliability of all pump station equipment, especially during power outages.
New automatic pump controls increased the ease of operation and reduced the need for daily attention from operators. Architectural improvements greatly improved the appearance of the station.
Schedule
Faced with a consent order from the PVSC, KMUA tasked Mott MacDonald to prepare a basis of design and preliminary design documents within 60 days. By meeting this deadline, we enabled KMUA to negotiate a schedule modification that allowed KMUA to participate in the State Revolving Fund. This saved KMUA more than $1 million in financing costs for the project. KMUA received beneficial use of the facility within the original contract time period.