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Unique Water Reuse Path in Tallahassee

Sondra W. Lee, P.E. President, FWEA

Across Florida there are a variety of water concerns, and thus, different methods of managing water resources, including how reclaimed water is utilized. The City of Tallahassee area seems to stand out from most of Florida’s larger cities when it comes to reuse. With an abundance of annual rainfall and accessibility to the Floridian aquifer, Tallahassee has avoided the water scarcity that other parts of the state are concerned with. This has led Tallahassee down a different path when it comes to water reuse.

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Pioneers in Reclaimed Water

Tallahassee began experimenting with effluent irrigation in 1966 on 16 acres of land located at the current Thomas P. Smith Water Reclamation Facility (TPSWRF) site. It’s believed that only the Penn State University project has a longer history of scientific investigation regarding the effects of treated wastewater effluent on crops, soils, and groundwater.

Over the years the Southwest Sprayfield, which uses treated or reclaimed water for effluent spray irrigation, was expanded, eventually reaching 121 acres. In 1971 Dr. Allen Overman, professor with the department of agricultural engineering at the University of Florida, began work on an project with the U.S. Environmental Protection Agency (EPA) at the city’s sprayfield, which investigated nutrient uptake by forage crops, effects of effluent irrigation on groundwater quality, plant/soil/nutrient interactions, cation transport, and phosphorous removal. The EPA issued its report titled, “Wastewater Irrigation at Tallahassee, Florida,” (EPA-600/2-79-151) in August 1979.

Following this study, the city implemented a full-scale irrigation operation. In 1981 the city completed work on the first phase of a sprayfield in the southeast area of Tallahassee, along with holding ponds, a pumping station, and an 8-mile-long force main at a total cost of $9,711,895. Because the sprayfield was considered “innovative technology,” a federal grant was received covering 85 percent of the cost.

The city continued to expand the Southeast Farm reuse irrigation areas so that, by 1984, the city stopped all surface water discharges, sending effluent only to the two sprayfields, becoming one of the first sites to beneficially reuse 100 percent of its water. The last expansion at Southeast Farm was completed in 1999, with a total of 2,160 acres under irrigation providing capacity for 26.3 million gallons per day (mgpd).

Award-Winning Reuse Facility

With Tallahassee’s early work in reuse, the Southeast Farm has won a few prestigious awards: S Outstanding Infrastructure Award from American City and County magazine in 1994 S First Place for the Most Effective and Innovative Reclamation and Reuse Program from EPA, Region IV, in 1995

Public Access Reuse Facility Comes to Tallahassee

In 2004 Tallahassee began to design and construct a small public access reuse facility near a new subdivision on the southeast boundary of the city. The facility delivers reclaimed water to a nearby golf course, state office complexes, and school grounds. Due to the cost of implementation, operation, and maintenance, the city was not interested in providing service to individual residences. Although sized to handle 1.2 mgpd, with plenty of room to double the capacity if needed, average annual flows have remained less than 0.7 mgpd since it was put into service in 2008.

Tallahassee Holds Course

Years later, not much has changed with the city’s reuse distribution system path. It would have been cost-prohibitive to supply reclaimed water throughout areas that were already developed. Then, since the sprayfield provided plenty of affordable distribution of effluent, the city’s infrastructure was expanded without including distribution piping for reclaimed water. There were, however, a few other factors that kept Tallahassee from changing direction.

Abundant Rainfall

The amount of rain in the area is one factor in the city’s decision to not heavily pursue a widespread distribution of reclaimed water.

Tallahassee receives approximately 60 inches of rain each year, providing a good source for the potable drinking water supply and a significant amount of water needed for landscaping purposes.

Beneficial Geography

The geography of the area also plays a factor in Tallahassee’s reuse course. The Southwest Sprayfield and the Southeast Farm are located south of the Cody Escarpment, the approximate location of an ancient shoreline. Clay layers were eroded away by wave action, creating areas that are incredibly sandy, providing intense recharge of surface water to the Floridan aquifer system. Also, the local geography has allowed easy access to the Floridian aquifer, contributing to an abundant water supply for Tallahassee.

Nutrient Runoff Concerns on providing reclaimed water to larger, but fewer, entities, as opposed to residential use. In fact, the city added language to the code of general ordinances stating that residential areas are not included as part of the allowable users for reclaimed water.

Another factor is the concern of some water industry professionals that stormwater runoff from users that overspray their irrigation of reclaimed water could negatively affect local water bodies by delivering too many nutrients. This may have been a valid issue prior to the facility upgrade that began in 2009 when total nitrogen levels were above 14 mg/L.

The Path Ahead

Tallahassee is still successfully operating the small reuse facility and the two sprayfields. Wastewater flows from the city’s collection system have remained very consistent for many years, so the city has not had to expand facilities since the 1990s, and capacity is expected to be adequate until beyond 2050.

The city is actually in a fortunate position to still have plenty of time to develop a plan on how to accommodate future flow increases. Some conceptual plans exist that will be further developed over the next few years to expand methods of using reclaimed water.

Although Tallahassee does not have an expansive, citywide, public access reuse distribution system like the rest of the state, the current reuse system is serving the city and the surrounding community well. S

Patrick “Murf” Murphy President, FWPCOA

eah, that’s me—an April fool!

Two months after writing my column about opposing House Bill 23, Water and Wastewater Facility Operators, as written, I was still concerned that gratuitous reciprocity was going to be given to any licensed operator that has not first demonstrated the training and experience acceptable to the Florida Department of Environmental Protection (FDEP) and passed a Florida operator licensing exam. In the column I posed comments and questions about parts of the bill, and solicited feedback from anyone reading the article.

I heard from six operators; each agreed with opposing the reciprocity section as it was written and a couple of them really wanted first-responder status. The bill did pass.

Two months after reaching out to the Florida House of Representatives and the Water Quality, Supply, and Treatment Subcommittee, the Hon. Yvonne Hayes Hinson was the only one who responded to me. I was very appreciative that she took the time to make that effort and I felt a little better about banging the drum.

If Ignorance is Bliss, Then Why Ain’t I Happy?

Being ignorant that I could have been at the meeting to discuss the bill and voice my

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