Water management

South Central projects treat, heat & transport water, wastewater

By James Gordon

Several, multimillion dollar water facility projects that dot the South Central region are inching closer toward projected completion dates.

The projects profiled here represent the full spectrum of construction of water- and wastewater-related infrastructure. They're projects that flow water to and from locations, heat and cool the water distributed around new locations and treat used water.

New development not only created a need for some of these projects, it also set up hurdles toward their completion, as was the case with a 14-mi. transmission line built to serve Bentonville and Bella Vista, Ark.

In the case of the new biosolids treatment plant in Nashville, Tenn., the difficulty arose from blending a new facility into an older community with a distinctive style of architecture.

Bentonville Water Transmission Line Extension, Bentonville, Ark. The city of Bentonville contracted Garney Construction of Kansas City, Mo., to lay 75,000 ft. of 48-in. concrete pipe to connect the Beaver Water Plant in Lowell, Ark., to a connection point in the Bentonville water system.

Project manager Tony Kempf said the $15.1 million contract is a run-of-the-mill job for Garney, which has completed several other similar projects in northwest Arkansas.

Britt Vance, Bentonville's utilities director, said the line extension was necessary to meet the growing needs of a booming area. Based on current projections, the line should be enough to serve Bentonville and Bella Vista for the next 20 years.

Ironically, the same growth in the area that created a need for the project has also spawned a hurdle toward its completion. Since the plans were drawn up by USI Arkansas, an engineering firm in Springdale, Ark., new roads were built or slated to be built intersecting with the 14-mi. path of the extension line.

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So Garney has had to go in before the roads were built to lay steel casing in the ground under which the new roads would soon run. In cases where the roads were already built, Garney subcontracted a company to bore under the new roads.

In spite of these impediments, Kempf said the project is expected to be completed on time in March.

District Energy Plant No. 1, Auburn, Ala. Robins & Morton Group of Birmingham, Ala., recently completed the $13 million District Energy Plant for Auburn University. The project was the construction of a new central energy plant to provide hot and chilled water for heating and cooling new buildings on campus.

Robins & Morton was contracted to manage the project exclusive of the direct costs of construction of the facility, much like a consultant or an architect. The three other contract packages - general, mechanical and electric - were contracted directly with the university.

The new energy plant, unlike the other few on the campus, has a medium-temperature hot water system, which boils water at about 240 degrees. Auburn also has plans to remove the steam facilities from its existing buildings, thus moving the entire campus to a medium-temperature hot water system.

Eric Eitzen, Robins & Morton's estimator for the project, said most of the costs of the project went to pay for the mechanical and electrical costs of building and hooking up the heavy boiling and chilling equipment.

Eitzen said the job took more than a year and was officially completed this summer. However, he said there are a few punch list items Robins & Morton are still working on.

Central Wastewater Biosolids Plant, Nashville, Tenn. Archer-Western Contractors Ltd. of Atlanta broke ground in November 2005 on a $117 million biosolids management facility for Metro Water Services in Nashville.

The existing metro solids facility, near the end of its usefulness, was long a source of unpleasant odor for the surrounding community. But the new facility will turn solid waste into a pellet fertilizing product and eliminate the odor problem, said Archer-Western project manager Kelley Hadley.

The scope of the project included the addition of five 2.5 million gallon digesters, four 65-ft. diameter dissolved air-flotation thickeners and a 50,000-sq.-ft. biosolids heat drying facility.

Hadley said the biggest design problem presented by the project was integrating the development of the facility into the distinct character of the community. Local architecture firm Barge, Wagner, Sumner & Cannon Inc. designed the facility with architecture and building materials similar to other buildings in the area.

The designs also included a biking and walking trail dotted with trees running adjacent to the site.

The new biosolids facility will receive peak flows of up to eight million gallons per day of co-mingled solids. The facility is scheduled to startup in June. Archer-Western predicts the project will be completely finished by June 2008.

Westside Wastewater Treatment Plant , Fayetteville, Ark. The $59.9 million Westside Wastewater Treatment Plant project is unusual because it is a new wastewater treatment operation "from the ground up," said Tom Marcum, project manager with Brasfield & Gorrie of Birmingham, Ala.

"There was nothing there," he said. "The transmission lines coming into the plant are being constructed as we speak." The plant consists of 27 structures that will consume 30,000 cu. yds. of concrete, which Brasfield & Gorrie is placing.

Among the structures are an operations building, inlet facilities, four biological units, four final clarifying tanks, storage units, and the tanks, holders and filters that are used to treat wastewater.

They will be connected by more than 13,000 ft. of iron pipe that is 6 to 60 in. in diameter, Marcum said. About 3,000 tons of reinforcing steel will be needed.

The final clarifying tanks, about 110 ft. in diameter, will have 15-in.-thick walls, he said. The oval-shaped biological tanks are about the size of a football field, built in a series that runs together.

The plant, which will use an ultraviolet disinfection system, will remove all the water from the waste, leaving solids that will be hauled off.

O.B. Curtis Water Treatment Plant Expansion, Ridgeland, Miss. Brasfield & Gorrie began a $42.7 million expansion at the O.B. Curtis Water Treatment Plant in April on the Ridgeland water treatment plant it originally built in 1989.

Fortunately, the owner - the city of Jackson - expected the expansion.

"When we built the original job, a lot of the work we did there was made to accommodate or facilitate this type of an upgrade," said Brasfield & Gorrie project manager Scott Sheumaker.

The addition of a submerged membrane filtration system will double the plant's capacity to 50 million gallons per day.

Brasfield & Gorrie will also make modifications to the plant's existing deep-bed filter system. The job includes enclosing the high-service pump station, constructing a block building with a structural steel frame and adding another enclosed high service pump station.

The project, not a particularly large concrete job for a treatment plant, will include about 16,400 cu. yds. of concrete. There will be plenty of new piping, however. The job calls for about 2 mi. of ductile iron yard pipe and 8.5 mi. of small-diameter pipe.

The plant will also get more than 70 new pumps of various sizes, some with as much as 800 hp.

The project is a joint venture with Dixon Interior Finishings of Jackson, Miss., and will be completed in December.