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The consensus in the scientific community, as noted in the recently published National Climate Assessment, points to an escalation in the frequency and intensity of severe weather events due to climate change. Natural disasters can cause serious disruptions to water and wastewater utility operations, as well as destruction and risk to human health. Fortunately, these negative impacts can be...

Aerobic granular sludge (AGS) is a potentially transformative technology based on fast-settling bioparticles that allow for greater hydraulic and mass loading capacities when compared with conventional activated sludge. Under the proper conditions, the technology can support a single sludge capable of nitrogen, phosphorus, and carbon removal. AGS research and full-scale installations employ the...

The City of Wilmington's James A. Loughlin Wastewater Treatment Plant liquid and solids treatment trains are currently being designed for upgrade and expansion to 16-mgd capacity. Class A residuals management alternatives were investigated as a part of the preliminary engineering phase due to concerns over the long-term viability, risks and economics of the current Class B land application...

Port Huron, Michigan began implementation of its CSO control program in 1997. As of 2012, the City had completed over 95% of the total program, with 32 of 33 projects completed or under construction, and with $171 million in expenditures. After considering both end of pipe controls and sewer separation, the City opted for separation. This decision was based on both the lower cost of the separation...

The City of Omaha is in the process of addressing combined sewer overflows (CSOs), as required by the Clean Water Act, U.S. Environmental Protection Agency (EPA) CSO Control Policy of 1994, and the City’s Administrative Consent Order with the Nebraska Department of Environmental Quality (NDEQ), to improve water quality in the Missouri River and Papillion Creek. One of the projects outlined...

Aging infrastructure is plaguing our Nation. The major cost of identifying, maintaining or rehabilitating sewer systems is a daunting reality for our communities. This paper presents one concept of identifying, recording and accounting for each lateral asset across a large metropolitan system. The effort was to account for each sewer lateral, record the condition, and develop an action...

 

Red rock canyons and eroded cliffs such as those found in southern Utah may be pretty to look at but they are also indicative of potential water quality problems. In the Colorado Plateau physiographic region of Utah, two common causes of water quality impairment are warm stream temperatures and Total Dissolved Solids (salt) concentrations. In several cases these impairments can be attributed to...

Limits on whole effluent toxicity (WET) now have been part of the U.S. Environmental Protection Agency's (EPA) National Pollutant Discharge Elimination System (NPDES) for more than a decade. While it is generally agreed that such limits are an important component of efforts to improve the quality of our nation's surface waters, implementation of WET limits in NPDES permits has been controversial...

Green Infrastructure (GI) practices attempt to mitigate the impacts of urbanization through water harvesting, infiltration, evapotranspiration, and reuse on a small-scale. Proponents of GI programs for some time have justified their case based on the potential advantages in cost-effectiveness and wider economic benefits compared to conventional ‘grey’ infrastructure. Today, a growing...

The Accreditation program is currently under development by AWWA. Accreditation will become a voluntary, nation-wide program for all utilities, regardless of size. It is a form of a verification of the application of standards of best practice to deliver high quality services and not an attempt to by-pass the regulatory compliance (it is “above & beyond”). It should result in less...

Improvements in sensor and automation technology in recent years have made it possible to design a system to control the key variable parameters in and around the dewatering process. By continuously analyzing feed conditions and output from the process, an automated optimization system can make necessary proactive adjustments to the internal settings of the dewatering equipment, the polymer dosage...