The City of Martinsville, Virginia, owns and operates a 6.2-mile-long gravity interceptor constructed of 36-inch and 42-inch corrugated metal pipe (CMP) and reinforced concrete pipe (RCP), which was installed in 1963. The interceptor was inspected utilizing multisensory technology, revealing severe defects from corrosion and overburden stresses created by industrial and commercial activities. One collapse of more than 80 percent required immediate implementation of an emergency pumping plan and execution of a highly complex repair.

Finding a Creative Funding Solution

After assessing the damage and brainstorming possible solutions, we assisted the city in mitigating risks associated with the 80 percent collapse and developed a comprehensive strategy to rehabilitate 4.2 miles of this interceptor. With our initial estimates between $40 million and $50 million, it was recognized that the potential financial impact to the city’s customers would be overwhelming without implementation of a more cost effective strategy. Additionally, a highly effective funding strategy had to be developed. Working with the city, a creative project delivery plan utilizing construction phasing and an alternate bidding method was implemented to ensure competitive pricing. A seamless funding strategy composed of grants and a low interest loan was developed. This strategy worked and resulted in all rehabilitation work being completed at a cost less than $25 million.

The project phases consisted of developing four contracts.

• Contract I: Emergency replacement of a 750 linear feet of collapsed CMP with highly complex site conditions.
• Contract II: Installation of 5,200 linear feet of parallel gravity sewer.
• Contract III: Alternatives selection of sewer rehabilitation methods, including replacing in place, cured-in-place pipe (CIPP) liner or parallel sewer installation. This contract incorporated flexibility in how rehabilitation methods could be selected by the contractor to develop the most cost effective project.
• Contract IV: Repair collapsed sewer and CIPP lining on an industrial site.

Contracts I-III were funded through the Virginia Department of Environmental Quality’s Revolving Loan Fund (DEQ RLF) program while Contract IV was primarily funded by a grant through the Economic Development Association (EDA).

Serving the Community Despite Challenges

Currently, Contracts I and II are complete while Contracts III and IV are in construction with expected completion in the latter part of 2018. As happens during most projects, we encountered a number of challenges throughout the project, some more unique than others. These challenges included significant infiltration, heavy sediment and debris deposits within the existing interceptor, bypass system malfunctions, unmarked utilities, vandalism, fire, freezing temperatures, instability of slopes and river embankments and resistive property owners. Even under this somewhat unusual set of circumstances, we are proud to be working with the City of Martinsville to deliver a project that will serve community members for decades to come.