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Under Pressure! Texas Water Tank Project JACK INNIS, CONTRIBUTING EDITOR PHOTOS BY RALEIGH WHITEHEAD A few months after the Texas War for Independence ended, two brothers formed a new town in the southeast part of the state. Houston is "handsome and beautifully elevated, salubri- ous and well watered," gushed the August 30, 1836, edition of the Telegraph and Texas Register. Water was plentiful back then. Early settlers simply dug wells or paid haulers seventy-five cents for 30-gallon (113.6L) barrels, delivery included. ), one of the most complex water systems in the nation. To slake the thirsts of approximately 2.8 million customers, the City of Houston Public Works and Engineering Department pumps, on average, 400 million gallons (1,514,164,713.6L) of water per day. That's enough to fill the Reliant Astrodome four times over. That's also a mighty tall order, especially during the most intense one-year drought since Texas began recordkeeping in 1895. Today, Houston relies on a 7,000-mile-long (11,265.43km) pipeline structure that stretches across four counties and 600 square miles (1,553.99km2 UNDER PRESSURE! Houston's sprawling pipeline system can't work without water storage and treatment facilities. So when corrosion sidelined a five-million-gallon (18,927,058.9L) tank in the summer of 2011, the coatings crew at Houston-based Blastco knew they'd be under pressure to get the job finished on time. Sure, the city could tempo- rarily reconfigure the water system to work without the tank, but any delay in getting it back online in the middle of the drought-stricken summer could result in a whole bunch of parched cowpokes. In addition to a new coating system inside and out, the five-million- gallon (18,927,058.9L) tank required comprehensive remediation that included replacing steel known to be in poor condition, upgrad- ing the tank's cathodic protection system, and installing new monitors and alarms. The tank's exterior would be sand-blasted to achieve NACE No. 3/SSPC-SP6 Commercial Blast Cleaning with a 2.5-mil (63.5 microns) anchor profile. The blast would ready the tank for installation of a Carboline coating system compris- ing a Carboguard Zinc 11 base coat, Carboguard 893 intermediate coat, and Carbothane 134HG topcoat. The interior would receive a NACE No. 2/SSPC-SP10 Near White Metal Blast with a 3-mil The Blastco crew used an ARS Super Unit self-contained mobile blast and vacuum rig to prep the tank's exterior. The unit recycles spent abrasives, generating ten 45-gallon (170.34L) drums of waste for the entire 80,000-square-foot (7,432.24m2 LEFT ) project. 54 CoatingsPro J July 2012