Catskill/Delaware Ultraviolet Light Disinfection Facility

Valhalla, NY
New York City Department of Environmental Protection
Malcolm Pirnie/CH2M HILL joint venture
$1.3 Billion

The Catskill/Delaware Ultraviolet Light Disinfection Facility is the largest capacity water treatment plant in the world. The project’s complexity is not only in its technology and construction processes, but in its size and scale. Project components include 10,000 linear feet of stainless steel pipe, more than a mile of field-cement-lined 12-ft-diameter pipes, and the largest UV units ever manufactured. Crews poured 121,000 cubic yards of concrete and installed 1,200 tons of structural steel. At peak construction, more than 800 workers delivered $30 million in construction per month.
One of the most challenging aspects of the project involved commissioning of the facility. From the initial introduction of flow, the facility had to actively manage more than 1 billion gallons of drinking water to NYC on a continual basis. However, the facility’s computerized flow control strategies could not be fully tested and commissioned without first introducing flow into the facility. During this commissioning period, the project team provided personnel on a 24/7 basis for more than a year who were dedicated to coordinating ongoing construction activities and assisting with the operation of the facility’s flow control equipment as it transitioned from manual to full automatic operation.


The scale of the Cat/Del UV project required an enormous amount of construction documentation. To address this, the CM team’s in-house staff developed a customized Construction Management Information System (CMIS) and SOURCE, a database software application that supports quantity data management and daily field reporting. SOURCE captured key information at the point of installation, such as installed quantity data, in a consistent format that supported the contractor’s payment requisitions, document time and material changes, and earned value calculations. The contractor’s detailed estimate breakdown and monthly pay applications were imported into SOURCE to produce one comprehensive database for payment validation purposes.
The Cat/Del UV project was originally designed utilizing standard 2D CADD, which was converted to 3D CADD and provided to the contractors at the recommendation of the CM team. The 3D model was used extensively in the coordination of the four prime contracts as well as to detect “clashes.” The 3D model was also used in developing the Critical Path Method (CPM) schedule though visualization of the project and was later linked to the schedule creating a 4D model of the project. The 4D model was also used to determine site access at different stages of construction and allow trade and inspection staff to visualize upcoming work.

L JV for their excellent execution in the delivery of the CAT/DEL UV Facility. The $1.3 billion construction project was executed in a manner that instilled our confidence in the team itself and in the delivery approaches implemented, all resulting in some of the best delivery performance metrics earned on any major DEP capital construction project. The CM team worked closely with our design, construction and operations staffs, as well as the construction contractors, to deliver this world class project on time and on budget.
The CM team’s leadership, led by Certified Construction Managers, directed the CM’s efforts emphasizing schedule, quality, cost and safety. The CM’s successful implantation of CM delivery methodologies greatly contributed to the success of the project.
The CM team’s performance displayed a consistent high regard for the interests of New York City and their desire to meet the expectations of the project stakeholders. Each member of the team is to be applauded for the results of their efforts as New York City is the proud owner of a new state-of-the-art UV disinfection facility that will serve as a standard for years to come.

Gerard Cox, PE


NYC Department of Environmental Protection, Bureau of Engineering Design and Construction