Trends Summer 2011 | Page 13

The silver filter (at left) at the Palatka, Florida, wastewater treatment plant provides high-level disinfection of reclaimed wastewater, which is then pumped through purple reuse lines to a holding pond. The biggest segment in the project involved installing 2,100 feet of new 16-inch water main under the Big Pass waterway between Siesta Key and Lido Key islands. The water main was installed using horizontal directional drilling (HDD), greatly reducing the project’s environmental impact. “Big Pass is a very highly traveled waterway in the community, sands are shifting all the time, and currents are very strong through the pass,” Haas said. “Trying to excavate a trench would be a real challenge.” Projects at the other three locations also had unique needs. The Bay Road water main involved installing a major transmission line down a county road to loop the existing City water network between Osprey Avenue and Tangier Terrace. The South Orange Avenue water main used HDD to cross the Hudson Bayou, plus jack and bore casing installation under a busy state highway to minimize traffic disruption. The Orange Avenue project replaced a 10-inch cast iron line that was so corroded its water flow was only equivalent to the capacity of a 4-inch pipe. The Osprey Avenue project replaced a 12-inch asbestos cement water main that had gasket failure problems. Haas said the biggest challenge was getting all the necessary state and local permits. “It took a lot of effort to get everyone to understand what we were doing, why, and how,” he said. “Ayres Associates was able to help us get all the appropriate permitting.” Communities and their engineers work together to make sure the water coming out of the tap is clean and safe. They also work together to manage and treat that water after it’s been used. The City of Palatka in northeast Florida is on the St. Johns River, a major environmental and recreational resource. In recent years, combined effects of stormwater runoff and wastewater treatment plant discharges have raised nitrogen and phosphorus levels in the river, decreasing its water quality. Today, Palatka is on the verge of having zero wastewater discharge into the river. The project started in 2005 with providing reclaimed water to irrigate the municipal golf course. Wastewater treated by the municipal wastewater treatment plant undergoes high-level disinfection by being run through filters. It then is pumped to a 13-million-gallon holding pond built specifically for this purpose at the golf course. Phase 2 was intended to provide reclaimed water to four ball fields within one-third mile of the holding pond. But during project