June 2010, Vol. 22, No.6

Taming the Wild West

UV disinfection guidance for potable water could provide the foundation of a much needed validation protocol for wastewater applications 

Feature 1 art Bryan Townsend, Gary Hunter, Christian Bokermann, Ronnie Bemus, and David Morgan

The varied approaches currently used by manufacturers for the design of ultraviolet (UV) disinfection systems for wastewater applications have resulted in an environment not unlike the “Wild West.” Techniques used for sizing and operating UV reactors range from mathematically derived intensity and flow distribution models to biodosimetry- based validation testing in accordance with a variety of standardized and nonstandardized protocols. Therefore, comparing and evaluating UV system designs by various manufacturers can be a difficult process marred by uncertainty.

In addition, many concepts that are vital to proper validation testing and application of biodosimetry results can be overlooked or misunderstood. As a result, a system can be underdesigned or overdesigned and hindered by inefficient operating strategies. Read full article (login required) 


The Cloud is Coming

What water and wastewater utilities need to know about social media 

feature 2 art Irwin N. Jankovic and Myron Olstein

The rapid growth of cloud computing and the pervasive spread of Web 2.0 social networking tools — Twitter, blogs, texting, and the like — are changing the business and personal communications landscapes at local and global levels. Customers are resetting their expectations for responsive customer service from ground-based timeframes measured in days to electronic response times measured in minutes, if not seconds. In parallel, many of these social networking tools offer businesses new and cost-effective ways to reach their customers and stakeholders for a wide range of value-added business purposes. Read full article (login required)


Operations Forum Features

A Rocky Problem

Mining industry supplies answers to grit-pumping problem 

Feature 3 art Sheldon Lipke, Jay Lovelass, JP Fortin, John Bolcar, and Bridget

The Passaic Valley Sewerage Commissioners (PVSC; Newark, N.J.) faced a rocky problem: A host of design, operation, and maintenance challenges plagued the 37-year-old headworks at its wastewater treatment facility. One challenge — pumping grit from closely spaced grit channels — proved particularly resistant to solutions used in the wastewater field, despite some innovative approaches. Unwilling to give up on the project, PVSC looked for help in the mining industry. Using the knowledge and experience of a trade that pumps rock slurries hundreds of miles, PVSC found its solution. Read full article (login required) 


Keys to Smart Bypass Pumping Design Criteria 

Feature 4 art Harrison Steed

When working to rehabilitate medium and large-diameter collection lines, ensuring adequate bypass pumping is essential. But, to date, no commonly accepted standard for sewer bypass design criteria has been developed. The level of detail provided in the design documents can vary significantly from one engineer to another.

While limiting liability is an important part of what an engineer does, a designer can take proactive steps on projects requiring bypass pumping to help save the owner money and make projects more successful. Read full article (login required) 


Disinfection Dos and Don'ts

A primer on the safe and effective handling of chemicals 

Feature 5 art Gerald F. Connell, Hari Kapalavai, Leonard Casson, and Gary Hunter

The goal of wastewater disinfection is to kill or inactivate waterborne fecal and pathogenic bacteria and viruses, and ultimately to protect public health. An important and often overlooked aspect of the disinfection process is the storage, conveyance, and safe and secure handling of disinfectant chemicals.

When using such chemicals as chlorine gas, bulk sodium hypochlorite, chlorine dioxide, or dechlorination chemicals, it makes good sense to review the best practices for their safe use. Read full article (login required)

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