Cat/Del Crews Carry Out Colossal Coordination
NINE MILLION New York City residents are depending on Welsbach Electric to meet a critical April milestone at the Catskill/Delaware Ultraviolet Disinfection Facility now under construction in Westchester County, north of the city.
The Queens, N.Y.-based electrical contractor is charged with powering up the $1.4-billion New York City Dept. of Environmental Protection (NYCDEP) project. With a capacity of 2 billion gallons per day, the Cat/Del project will be the world’s largest UV facility when fully operational in October 2012 and will deliver 90% of the city’s drinking water.
Welsbach must connect the plant to the local utility in order for crews to begin preliminary testing to meet NYCDEP’s schedule to have half of the facility on line by Aug. 31, 2012. It is the latest deadline on a list of 11 interim milestones—each with liquidated damages—for the tightly scheduled project.
“We do a lot of public work with New York City for the Department of Transportation and other large DEP projects, but this project is something special,” says Kenneth Brouwer, Welsbach vice president of industrial/commercial. “Everyone on the project is bringing his A game, from the owner to the lowest-tiered subcontractor. It brings a level of excellence for all contractors involved.”
Tight Teamwork
Since the groundbreaking in April 2008, crews have steadily churned out high volumes of work at the 63-acre site near Mount Pleasant, N.Y.
To help meet the 59-month schedule, Skanska USA, Whitestone, N.Y., formed the SEW joint venture with Ecco III Enterprises, Yonkers, N.Y., and J.F. White Contracting Co., Framingham, Mass., under a $1.1-billion general contract. Welsbach signed a $107.5-million prime contract, the largest electrical contract ever written by its parent firm, EMCOR Group.
Other prime contracts include a $58.5-million pact for HVAC work and a $20.5-million contract for plumbing work, both won by L.J. Coppola Inc., Thornwood, N.Y. The design team is a joint venture of Hazen and Sawyer, New York City, and CDM, Cambridge, Mass. A joint venture of Malcolm Pirnie, White Plains, N.Y., and CH2M Hill, Englewood, Colo., is performing $82 million in construction management services.
Supersized Structures
The 165,000-sq-ft project includes seven structures, which are sited on rock and mostly made of reinforced concrete. The main UV building has a steel superstructure. A series of underground structures and waterways will tap into an existing concrete uptake shaft to transfer water from the shaft to large holding tanks in the plant. Valves and sluice gates will control the flow of water from the tanks to 56 UV treatment units.
Although the UV facility contains several highly complex systems, Keith Chouinard, Skanska’s vice president of operations, insists that the challenge of delivering Cat/Del is the sheer enormity of the project, as well as its components and fast-paced schedule. “It’s the largest contract that I’ve been involved with,” Chouinard says. “Everything at Cat/Del is supersized.”
Not only are the components large, like the 12-ft-diameter pipes and 19-ft-long, 5.5-ft-wide and 7.5-ft-tall UV units, but there are large quantities throughout the project as well. Upon completion, crews will have placed 10,000 linear ft of steel pipe and field-cement-lined more than a mile of 12-ft-diameter pipe. In addition, crews will have welded 131,000 inches; poured 121,000 cu yd of concrete; and installed 1,200 tons of structural steel, 522 pieces of blast-proof architectural precast and 20,000 sq ft of aluminum grating.
“We had more than 600 critical picks for the project,” Chouinard says. “It wasn’t so much that we had any unique cranes or picks in general. It was the quantity of picks and the fact that everything was big and needed a crane.”
Picks averaged 55,000 lb each, with the largest being 90,000 lb. “On a daily basis, we make two or three picks a day, as just a matter of normal business,” Chouinard says. “Each pick requires a tremendous amount of engineering, including a pick plan and ground study. We also had to coordinate crane access, availability and hook time.”
Additionally, large materials with permit loads are regularly delivered from all over the world. “We’ve got just-in-time delivery from Korea, France, Canada and, in the continental U.S., as close as Rhode Island to as far away as Minnesota and Kansas City,” Chouinard says. “A lot of those permit loads are only allowed to travel at certain times of the day, so that takes a lot of coordination.”
Coordinated Effort
The number of stakeholders on the project makes coordination essential. The design team developed 3D modeling of the project that was a real asset to the contractors, says Mark Hanson, project director for the Malcolm Pirnie/CH2M Hill joint venture. “It helped to coordinate between trades, with scheduling, and even figuring out crane locations and picks,” he says.
Contractors uploaded shop drawings electronically using Constructware software. The design and construction management teams reviewed and returned drawings using the same software, expediting the review period. Likewise, the Malcolm Pirnie/CH2M Hill team used a custom-designed Construction Management Information System developed specifically for NYCDEP to track all project correspondence, change orders, payments, requests for information and permits, Hanson says.
Down (in) the Drain
Water will be fed into the UV facility via Shaft 19, a 1940s-era shaft that conveys water up to grade from aqueducts 400 to 1,200 ft deep. About 1.6 billion gallons pass through Shaft 19 daily, so the SEW venture had to be very sensitive to it while excavating and backfilling 650,000 cu yd of material and blasting 30,000 cu yd of rock.
Currently, SEW is performing work in Shaft 19 on a drain valve that is stuck in the open position. The contractors must either close the valve or put a flange on it and plug a 16-in. pipe, Hanson says. SEW has already completed exploratory dives into the shaft, which required close coordination with NYCDEP operations and periodic shutdowns, Chouinard says.
“Due to the complexity of the work, the contractor is currently building a full-size mock of the dive and platform he will have to construct on the downstream shaft in order to plug the pipe between the uptake and downtake shafts,” Hanson says. “This work has to be completed by May, after which shutdowns of the aqueduct are not possible due to increased water supply demands to the city that come with the warmer weather.”
Workers enclosed the building housing the UV treatment units on Jan. 25, and are set to place all of the units by the middle of March. The emphasis moving forward shifts toward getting the facility powered and ready for “testing, startup, commissioning and turning it all over to the NYCDEP’s Bureau of Water Supply,” Hanson says. “While we can do some preliminary testing prior to this, getting power is the prerequisite to really starting the checkout and testing of the facility.”
Utility Con Edison will deliver power to the site, but Welsbach is tasked with “stepping it down” from two 13.2-kilowatt volt feeds to 5-KW volts, and then to 5-KW points that will accommodate each of the 480-volt UV units, says Scott Brouwer, the electrical contractor’s onsite project manager.
By January, Welsbach’s scope of work was 40% complete, having installed 570,000 ft of galvanized conduit pipe and more than 4.5 million ft of wire required to power the facility’s 56 UV units and standby generation and uninterruptible power supplies.
“[Uninterrupted power supply] will provide a bridge between loss of power and full onset of generator power,” Welsbach’s Kenneth Brouwer says. “It’s this huge, multimillion-dollar system to provide about 30 seconds to the site so there won’t be a disruption to the water supply.”
So far, the team’s extensive coordination efforts have paid off. Hanson says the project is on budget and ahead of schedule.
Still, Chouinard isn’t content to ease up. Now that the project has progressed to the mechanical and electrical phases with more milestones on the horizon, he says it will be a challenge to “keep everyone moving in the same direction and stay focused on the task at hand—the startup phase.”
