Underground Construction Association of the Society of Mechanical Engineers
Narragansett Bay Commission
Narragansett Bay Commission Combined Sewer Overflow Abatement Program

The Underground Construction Association of the Society of Mechanical Engineers (UCA of SME) chose the Narragansett Bay Commission for its 2009 Project of the Year Award. The Louis Berger Group, Inc. (Berger) was the Program Manager/Lead Design Manager (PM) for developing a comprehensive combined sewer overflow (CSO) abatement program. The program focused on the cities of Providence, Pawtucket, and Central Falls, Rhode Island, NBC CSO service area.

Berger completed a comprehensive Combined Sewer Overflow (CSO) Facilities Plan in 1993, which was approved by Rhode Island Department of Environmental Management (RIDEM) in 1994. In 1994, after submission of the plan, USEPA promulgated a new CSO policy that focused on water quality benefits and allowed either a "presumptive" approach or a "demonstration" approach to development of CSO control plans. NBC and LBG initiated a CSO Reassessment to take advantage of this change in policy.

During the reevaluation process, Berger examined and formulated 16 new system alternatives. These alternatives along with the originally proposed plan were evaluated using cost, environmental impacts, operational concerns and water quality improvements based on model data from design storm data. A stakeholder’s process was used to ensure widespread public involvement. The recommended plan consists of a combination of technologies resulting in a cost reduction of approximately $170 million.

Phase I of the plan was a 16,000 feet long, 26 foot I.D. deep rock tunnel, with a 50MGD pump station at tunnel depth. There were seven drop shafts with connecting surface structures conveying flow to the tunnel, and a number of regulator modifications to enhance system operation.

Berger divided the program into eleven construction contracts and was responsible for developing the bid packages and managing the bid process. Construction on the first contract started in May 2001; the final contract was completed in June 2007. Berger also provided total program management of the construction process, to include construction oversight, and assisted the NBC on all administrative aspects of the program.

The Underground Construction Association of the Society of Mechanical Engineers Project of the Year Award recognizes an individual or a group that has shown insight and understanding of underground construction in a significant project, which may include a practice, developing concepts, theories or technologies to overcome unusual problems within a project.


Related Projects

Narragansett Bay Combined Sewer Overflow Abatement Program | Providence, RI, US

More than 20 years ago, the Narragansett Bay Commission retained Louis Berger to develop a combined sewer overflow abatement plan. Experts at Louis Berger have served as an extension of the commission staff in managing all aspects of the abatement program.    More >