WE&T Magazine

WET_cover1_March14_90Water Environment & Technology (WE&T) is the premier magazine for the water quality field. WE&T provides information on what professionals demand: cutting-edge technologies, innovative solutions, operations and maintenance, regulatory and legislative impacts, and professional development.

 


March 2014, Vol. 26, No.3

Featured Articles

Cost-effective application of peracetic acid for high-level disinfection

Betancourt feature 2

The City of Largo, Fla., took a new approach to disinfection at its Advanced Wastewater Reclamation Facility (AWWRF) to meet new consent order mandates. The consent order from the Florida Department of Environmental Protection required the city to lower dichlorobromomethane (DCBM) concentrations in its surface water discharge at the facility to below 22 μg/L, the numeric limit in the state of Florida. DCBM is formed when chlorine mixes with organic compounds in final effluent.   

The challenge was to find a cost-effective disinfection alternative to chlorine for an effluent with a low UV transmittance.  

 

Out of sight, out of time

Barraco feature 1

The Trinity River Authority (TRA) Central Regional Wastewater System (CRWS) facility provides wastewater collection and treatment services for 1.2 million people in 20 cities and the Dallas–Fort Worth Airport.   

CRWS has 8 km (5 mi) of in-facility drain lines that collect return flows from all across the facility, with a majority of the flow passing through a 1500- and 1800-mm (60- and 72-in.) pipe to the influent pump stations. When a construction-related exposure of a manhole upstream of the 1500-mm line exposed signs of severe corrosion and the potential to collapse, TRA declared an emergency repair and immediately began the process to locate and approve emergency construction funds. 

 

Special Section: Smart Meters

Special Section This special advertising section discusses the capabilities and uses of on-line instrumentation and smart meters. Hear from manufacturers and users how these tools enable water and wastewater utilities to leverage technology into enhanced treatment, lower costs, faster responses, and more robust customer service. Read More 

 

News

How to slow down the tide

news

Researchers say water rates will continue to increase, but there are things utilities can do to reduce operational costs and rates in the future 

Read more

Coming in the next issue:
WET_cover1_April14_90

Flow control

There are many steps to preventing excess flows from escaping untreated. These range from maintaining collections systems, to making operational changes in pump stations and treatment facilities, to building new storage and treatment facilities at the end of the pipe. Looking closely and objectively at each of these steps can help stem surplus flows. 

Eliminating inflow and infiltration (I/I) can help prevent overflows. One method for making I/I investigations and repairs more effective is to use pump station data to pinpoint unusual increases in flow. Readily available pump station runtime data can prioritize areas for field evaluations and sewer evaluations as well as renewal and replacement projects. The tool also can identify service areas that do not exhibit I/I and therefore can be eliminated from expensive field evaluations. 

Having an operations plan is important. For example, in December 2011, the City of Portland, Ore., completed the last phase of its 20-year combined sewer overflow (CSO) control program. This program includes nine prioritized objectives that establish the basis for a clear decision-making hierarchy for real-time, system-wide operations. Prioritization is critical because the goals for operating the collection system, CSO control, and treatment systems can be in conflict. Operators must know what is most important to achieve when these conflicts arise. 

Even with the best plan in place, sometimes there is just too much water. The Trinity River Authority in Arlington, Texas, faced this situation, and responded by building a nimble treatment and storage facility for wet weather management. The new system increased the utility’s daily average capacity, provided cost savings when compared to conventional expansion and blended flow treatment methods, and increased flexibility in wet weather flow operations. 
   

Also in this issue    

  • Payback in the Outback: Small facilities lacking  preexisting anaerobic digesters make a positive business case for codigestion.   
  • Bubbling trouble. Causes and prevention of anaerobic digester foaming.   
  • Is salt the ‘sleeping dragon’ of wastewater pollutants? With U.S. EPA developing new chloride limit criteria, the water quality field eventually could face significant challenges.