Last year, the Washington Suburban Sanitary Commission celebrated its centennial—a milestone that marks the utility’s long experience in water and wastewater and illustrates the daunting challenge it faces to maintain a large inventory of aging infrastructure. WSSC has grown to be the eighth-largest U.S. water and wastewater utility, serving approximately 1.8 million residents in Montgomery and Prince George’s counties in the Maryland suburbs of Washington, D.C. Its system covers nearly 1,000 square miles and includes 5,768 miles of fresh-water pipeline and 5,578 miles of sewer pipeline.

Among WSSC’s greatest challenges is the pressing need to repair, replace or rehabilitate aging pipelines. More than one-third of its water mains are more than 50 years old, effectively at or near the end of their expected life spans. In recent years, WSSC has drawn on decades of experience and a desire to pursue forward-looking solutions to aggressively address infrastructure issues. In light of its efforts, ENR MidAtlantic has named the Washington Suburban Sanitary Commission its Owner of the Year.

WSSC管道建筑部负责人约翰·米切尔（John Mitchell）说，过去，该公用事业通常采取了保守的方法，但它越来越多地采用创新，以发展更好，更快，更便宜的方法和方法。从历史上看，需要更换管道的决定是基于年龄，土壤状况和工作历史等因素。如今，WSSC使用各种技术来更准确地确定需要更换的管道。“我们必须变得聪明，”米切尔说。“有了我们的烟斗，我们就无力出去替换可能拥有更多寿命的管道。”

To help monitor its prestressed concrete cylinder pipe (PCCP), WSSC began installing an acoustic fiber optic cable (AFO) system in large diameter PCCP more than a decade ago. The cables float inside pipes and monitor for acoustic “pings” that indicate breaks in the pipes’ reinforcing-steel wires. WSSC has 145 miles of PCCP, ranging from 36 in. to 96 in. in diameter. As of 2018, 102 miles of the pipe were monitored with AFO—making it the longest AFO monitoring system in the country, according to WSSC. The monitoring system includes other technologies, such as Pipe Diver, a long-distance, free-swimming condition assessment tool that can be used while pipelines are in service.

WSSC reports that between 2010 and 2018 the monitoring system, which cost $21 million to install, identified 20 damaged pipes. By allowing crews to make proactive repairs rather than expensive emergency fixes, the utility estimates that the effort resulted in a cost saving of $42 million. In addition, inspections showed that about 95% of the monitored pipes were in “like-new” condition. Less than 2% required immediate rehabilitation or replacement, according to Pure Technologies, the system provider.

随着WSSC增强其监控工作，它也开始加强其水主置换计划。到2012财政年度，WSSC每年将替换50多英里的水主要。该计划在2017财年以65英里的管道置换达到顶峰。

Mitchell says that in recent years, the program was able to focus on the “low-hanging fruit” in identifying its replacement needs. The remaining pipes, particularly those with smaller diameters, are more challenging to monitor. He says, “We will back off on our mileage in the next few years to about 25 miles per year, while we explore new technologies to assess the condition of pipe—and then we will start to ramp up again.”

作为其水主置换程序的一部分，WSSC还开始指定镀锌延性铁管，以通过更好地控制腐蚀来帮助延长管道的寿命。欧洲涂有锌的管道已经在欧洲使用了数十年，但在过去十年中仅由美国主要公用事业安装。

WSSC also specifies that its pipes must be wrapped in V-Bio enhanced polyethylene encasement for an additional external layer of corrosion control. WSSC expects that pipes specified with the two materials will last at least 100 years, compared with conventional iron ductile pipe’s expectancy of 50-plus years. WSSC claims that it is the first utility in the U.S. to specify a combination of the two materials.

Given the pipes’ unusual nature, Dan Hamilton, construction manager in WSSC’s pipeline construction division, says that sourcing pipes and getting them delivered just in time on projects was initially a challenge. “Contractors were supplying materials at first, but now we’re at the point of supplying most of the pipe on our own directly through our relationships with manufacturers,” he says.

工程公司Gannett Fleming的高级项目经理Dennis Funk说，近年来，他看到WSSC在管理其资产的方式方面变得更加进步。Funk说：“他们在跳入之前对自己的工作进行了很多思考，但是我发现它们对不同的想法和方法非常开放。”

加尼建筑中部大西洋地区副总裁史蒂夫·福特（Steve Ford）表示，自从他的公司开始为公用事业公司做大型项目以来，他已经看到了WSSC Evolve。新利18备用网址福特说：“当时和今天，可以说他们的期望很高。”“不同之处在于，当我们开始使用时，它们更加僵化，不太开放。他们现在并没有快速改变，但是当他们实施创新时，重点是资产管理，并确保他们投入的资产将持续很长时间。”

Garney is one of 10 companies that are in a WSSC indefinite delivery/indefinite quantity contract pool, which the utility typically uses for smaller projects. It turns to traditional design-bid-build delivery for larger pipeline projects. Ford says that Garney and other companies look forward to seeing WSSC use more alternative-delivery methods in coming years.

全心全意地Grojean WSSC设施设计和construction division leader, says the unit has let a few projects under a construction manager at-risk method. It is currently testing a range of design-build projects, including one valued at $220 million and one of $5 million.

Hamilton says the pipeline division will review the results of the facilities division’s alternative-delivery pilot projects and determine how they could be applied to pipeline work.

展望未来，WSSC正在针对创新的其他机会。将近一年的时间，它鼓励员工集思广益，研究和确定该公用事业在未来几年可以实施的新想法。WSSC将在5月举行“创新日”，员工可以提出建议。