Steel Pipe Project Extends Award-winning Tradition
The Central Regional Wastewater System (CRWS) in Texas is no stranger when it comes to receiving industry awards for wastewater treatment excellence. A recipient of the prestigious Water Environment Federation Outstanding Achievement in Water Quality Improvement Award, CRWS has also been recognized by the Environmental Protection Agency Region 6, the Texas Commission on Environmental Quality, and the Water Environment Association of Texas.
Located approximately three miles south of Dallas, CRWS is a four-time National Championship Winner of the Water Environment Federation Operations Challenge Competition and has earned multiple platinum, gold and silver awards from the National Association of Clean Water Agencies.
Earlier this year, the CRWS continued its winning ways when a new Influent Pump Station (IPS) was voted Steel Water Pipe Project of the Year for 2013 by the Steel Tank Institute / Steel Plate Fabricators Association.
Using selection criteria such as uniqueness, design, engineering, and aesthetics, the award was presented in March to Mid America Pipe Fabrication & Supply Co., Inc., of Scammon, Kansas. The fabricator supplied the CRWS with more than 1,300 linear feet of various-sized steel piping that originated at the plant’s six new pumps, passing through two separate vaults, and tying into existing forced mains.
Over the past decade, the CRWS has invested more than $750 million in infrastructure improvements as part of its long-term strategy for wastewater flow management. Owned by the Trinity River Authority in Dallas, Texas, the CRWS achieved a significant milestone in 2013 when it became one of the first sanitary sewer systems in the country to have treated and discharged 1 trillion gallons of wastewater during its 55 years of operation.
In an article marking the occasion, the CRWS newsletter, inTRA, reported that 1 trillion gallons would submerge Dallas and Tarrant counties in Texas in nearly three feet of water. Distributed across one square mile, that volume of water would be more than 4,795 feet deep.
In comments reported by inTRA, CRWS Project Manager Bill Tatum observed, “Back in 1959, CRWS was designed to treat 30 million gallons per day as a trickling filter, oxidation wastewater facility. Today the plant can treat monthly average flows of 162 million gallons per day.”
With more than 200 miles of collection system pipeline, the CRWS is committed to meeting its infrastructure needs while keeping costs reasonable for more than 1.2 million customers. For its new influent pump station, the CRWS realized significant cost savings by allowing the pipe fabricator to apply a 100 percent solids, ceramic epoxy lining specifically designed by Tnemec for steel and ductile iron pipe and fittings in severe wastewater applications.
Series 431 Perma-Shield® PL was approved for the IPS based on performance data and lower cost compared to another manufacturer’s field-applied lining system that was part of the original specification, according to Rick Penner of Midwest Coating Consultants, Inc. “The field application was going to cost three or four times more than we were proposing,” Penner explained.
“Cost was definitely a factor in switching products,” recalled Dean Gravett, project manager for Mid America Pipe Fabrication & Supply. “We had met with Rick Penner to see if he had a solution for the application and he suggested Series 431, which we were able to get approved. It was definitely a cost savings for everyone.”
Penner worked closely with coating consultant John Barry of The Barry Group, LLC, in Frisco, Texas, to provide the technical support and performance data requested by Gravett and the IPS project’s engineers.
Among the testing data provided were results based on ASTM G210-13 Standard Practice for Operating the Severe Wastewater Analysis Testing (S.W.A.T.) Apparatus, as well as ASTM standard tests for abrasion, adhesion, chemical immersion, salt spray and water absorption, among others. At the conclusion of all of these tests, the Series 431 lining displayed no visible cracking, blistering, or loss of adhesion.
Penner credited Gravett and the coating applicators at Mid America Pipe Fabrication for their excellent internal quality standards and adherence to manufacturer recommendations. Citing the distinctive green color of Series 431, Penner noted, “All of the parties involved that have seen the lining after application, in the shop and in the field, were truly impressed with the look and consistency of the end result.”
Prior to being shipped to the jobsite in Dallas, the interior surface of the pipes was prepared according to SSPC-SP5/NACE No. 1 White Metal Blast Cleaning with a minimum 3.0 mil profile. The lining was spray-applied at 40 to 50 mils dry film thickness (DFT) using plural component equipment.
“Our applicators loved it,” Gravett acknowledged. “It applied easily and provided a nice finish. We’ve used it on a couple other projects and are happy with its performance.”
Gravett cited Penner and Barry for their technical knowledge and support throughout the IPS project, which was completed in August 2013.
“Without their help, this project could have been a lot more difficult,” Gravett added. “Rick bent over backwards to help us out and to make sure we were giving the customer the best product possible.”