Colossal Overhaul

N.Y.C. Agency Takes on Slew of Expansion, Repair Projects

by Tom Stabile, Natalie Keith, and Kyla K. Wilson

New York City’s size and complexity as an urban center make it little surprise that its environmental construction and engineering projects are among the largest and most intricate in the region.

The menu of projects runs the gamut from a multiyear, $4 billion overhaul of a major wastewater treatment plant in Brooklyn to emergency repairs to an important dam on one of the city’s Upstate New York reservoirs that helps to supply the millions of gallons of water that the city consumes each day.

And the list is only growing. The current 10-year New York City Department of Environmental Protection capital plan clocks in at $17 billion, which is about double the rate of construction work that the city had been handling only a few years ago, says Alfonso Lopez, deputy commissioner of the department’s bureau of engineering, design, and construction.

“We’re doing the next capital program now, and the number will be significantly more than $17 billion,” he says. “We don’t look at the $17 billion as a blip or a spike. We see it as a new plateau.”

Lopez says the push for new construction is hitting all sectors in his division, from upgrades and additions to the city’s 14 wastewater treatment plants to construction of new drinking water filtration and ultraviolet radiation facilities. Other items are the ongoing construction of the city’s new water tunnel project and the upgrades to dams in the Catskills region.

The new work is responding largely to two pressures. The first is the need to upgrade facilities built in the 1960s and 1970s that are nearing the end of their useful lives in terms of technology, especially in the highly corrosive atmosphere of wastewater treatment. The other is the heightened level of water quality, water treatment, and other standards that the state environmental departments and the federal Environmental Protection Agency are requiring municipalities to meet in their water and sewer systems, particularly in the area of removing nitrogen in effluent flowing from four plants into the East River and Long Island Sound.

“The nitrogen removal program for those four plants will cost about $800 million, but there is another $2.4 billion in related work that we have to do at those sites,” Lopez says.

The upshot is that New York contractors and designers in this sector will be exceptionally busy in the next few years, largely because the city’s environmental department has a management oversight role, but leaves the design, engineering, construction management, and actual construction tasks to the private sector. While Lopez plans to staff up his office of project managers who coordinate these large efforts, the model will not change.

“We don’t do construction management or design, but we manage the consultants who do that work,” Lopez says. “We think there is significant capacity in the marketplace, though we are looking to attract new design consultants that we haven’t work with before.”

Even now, the oversized menu of projects seems surreal in scope:

• Upgrades to 12 of the city’s 14 existing wastewater treatment plants, including the nitrogen retrofits to the Hunts Point, Bowery Bay, Tallmans Island, and Wards Island plants.

• The new $1.24 billion Croton water treatment plant under construction in Van Cortlandt Park in the Bronx. The project, which broke ground in 2004, will treat up to 290 million gallons of water per day upon its completion in 2011.

• The new $570 million Catskill/

Delaware Ultraviolet Light Disinfection Facility under construction in Mount Pleasant, N.Y. The water disinfection plant, slated for completion in 2010, would also have support facilities in nearby Greenburgh. It would disinfect water coming from the Catskills region.

• continuing work on the city’s Water Tunnel No. 3 project, a four-stage, multiyear effort to add needed backup to the city’s first and second water tunnels, which date to 1917 and 1936. Last year, the department’s contractors, including J.F. Shea Construction of Walnut, Calif., Schiavone Construction of Secaucus, N.J., and Frontier-Kemper Constructors of Evansville, Ind., completed excavation of the main section 400 ft to 800 ft below Manhattan, creating 8.5-mi of tunnel in a $1 billion stage. The full No. 3 tunnel project will cost $6 billion upon its completion in 2020, but the next phase of shaft-digging and concrete lining of the main tunnel is taking place in the next few years in an effort to open the most recent segment for use by 2012.

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Fast Fix, Big Rehab for Gilboa Dam               

One of the most technically challenging projects on the department’s roster actually isn’t one of its largest but is among its most urgent. A pair of construction projects to strengthen the Gilboa Dam on the Schoharie Creek in Upstate’s Schoharie County got under way last year with an emergency $24 million stabilization effort that finished in December. It will be followed by a full-scale $300 million reconstruction project in 2008.

The threat of a spring thaw bringing flood conditions to residents downstream of the 20-billion-gallon Schoharie Reservoir was the main impetus of the reconstruction plans for the  2,000-ft-long and 182-ft-high dam. They were drawn up after a 2005 engineering analysis of the system’s dams found that the 1926 Gilboa structure, an earthen embankment and concrete spillway, was no longer adequate to keep back a flood that rose 8 ft above its spillway.

The city decided to take on a four-stage initial project that included installing a debris boom across the reservoir to keep objects off of the dam and installing a 220-ft long by 5.5-ft high notch at the western end of the dam, which lowered the capacity of the basin to relieve water pressure. Both were concluded early last year, along with a third stage to install four large siphons over the dam to increase the amount of water that can be drained.

The four siphons have a capacity of 125 million gallons per day each, and extend over the dam and onto the downstream spillway. Installation of the siphons was complicated by harsh winter weather conditions and the restricted space onsite to store equipment and materials, says Craig Valente, project engineer with D.A. Collins, of Mechanicville, N.Y., the contractor for that task. 

“We had two rain events where we had to shut down completely,” he adds. “That time of year the wind and cold are harsh, but workers just bore down to get the job done.”

The last stage involved installation of 79 anchoring cables through holes drilled into the dam and into solid bedrock beneath. They were then anchored in place and tightened, creating a system that helps hold the dam in place. That task was completed in December, says Dino Kartofilis, district manager for the contractor, Nicholson Construction of Cuddy, Pa.

To gain access to the dam and install the anchors, drill rigs were placed on a 26 by 450 ft working platform. The anchors had 58 strands of steel and were up to 250 ft long.

“The weight, size, and length of the anchors posed a challenge,” Kartofilis says.

The longer-term reconstruction to bring the dam into compliance with modern dam standards is in design. The project will include new water release works that will enable downstream releases to the creek, as well as rehabilitation of the intake structure for the Shandaken Tunnel, which conveys water south from the reservoir to the Esopus Creek and other points downstream.

The effort is well appreciated by local authorities who in the past had not had close relationships with New York City officials managing the water system, says Earl VanWormer, chairman of the Schoharie County Board of Supervisors.

“It took a lot of baby steps and learning and really frank discussions and even some difficulties,” he says. “Now, we’re taking several deep breaths. But we’d like to see the total reconstruction done.”

Large Overhaul at Newtown Creek          

One of the largest projects in the plans is the $4 billion expansion of the Newtown Creek Water Pollution Control Plant in Brooklyn, a facility that treats 205 million gallons of wastewater per day and has remained in operation during a major overhaul that will up its capacity by 105 million gallons and revamp its systems.

The work began in 2001 and is slated to finish before a consent order with the EPA in 2013 to bring it into compliance with federal wastewater regulations. And it involves many of the region’s major civil construction contractors, Lopez says.

“It’s Skanska, Picone, McCullagh, Perini, Silverite, Tully, Pegno and more,” he adds.

The site remains in operation and is hardly welcome to construction, Lopez says. The team must coordinate with nearly two dozen contractors and their associated equipment, deliveries, and crews.

“It’s a very constrained site, even with new property that we acquired, so construction is expensive,” he adds. “You’re trying to operate the plant while you’re rebuilding it, and we’re asking contractors to work on top of each other.”

The slate of tasks includes building 16 new digester tanks and a chlorination disinfection facility, pouring 162,000 cu yd of concrete, excavating 300,000 cu yd of contaminated soil, and installation of various pumps and extensive piping. There will also be extension demolition onsite.