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40 • OCTOBER 2009 • FLORIDA WATER RESOURCES JOURNAL

Aco-funding agreement between theSouthwest FloridaWaterManagementDistrict and Tampa BayWater was ex-

ecuted in May 2007 to define a program formeeting the future water supply needs of theTampa Bay area. This agreement establishedthe Configuration II program and a co-fund-ing commitment of $116 million by the watermanagement district.

By implementing the Configuration IIprogram, which includes expansion of exist-ing water supply facilities and construction ofnew facilities, Tampa BayWater will be able tointegrate, manage, and enhance the surfacewater supply source, ensuring that the agencywill be able to meet increased demandsthrough 2019. The expanded system will con-tinue to be drought resistant with use of theexisting 15-billion-gallon Regional Reservoir.Neither the original configuration nor the ex-pansion can be made drought proof, however,due to the naturally occurring climatic cyclesof rainfall and deficit in west-central Florida.

There are 10 projects included in this pro-gram (Figure 1), divided among two cate-gories: the four System Interconnects and thesix Surface Water System Expansion projects.This article will focus on the six SurfaceWaterSystem Expansion projects.

Existing facilities to be expanded are theTampa Bypass Canal Pump Station, the Re-gional SurfaceWater Treatment Plant, the Fa-cility Site Repump Station, and the HighService Pump Station. New facilities includethe Off-stream Reservoir Pump Station and

Tampa Bay Water’s Surface Water System Expansion

Amanda Rice and Nicole Thomas

Amanda Rice, P.E., is a senior manager forconstruction with Tampa Bay Water, a re-gional agency created by interlocal agree-ment to provide wholesale water to severalcounties and cities in the Tampa Bay area.Nicole Thomas, P.E., is a facilities managerwith Tampa Bay Water. Both work in theagency’s Clearwater office. This article waspresented as a technical paper at theFlorida Section AWWA Fall Conference inDecember 2008.

Figure 1:Configuration IIProgram Projects

Continued on page 42

Figure 2: Tampa Bypass Canal PumpStation


the South-Central Hillsborough IntertieBooster Pump Station. In addition, a pipelinesurge protection program has been includedto support the increased capacities and pres-sures associated with the program. Over 100air valve assemblies will be added or modified.

The benefit of the expansion is that theaverage production from the treatment plantis expected to increase from 55million gallons

per day (mgd) to 84 mgd during average rain-fall years.

All the Surface Water System Expansionprojects are underway, and as of August 2009, allare in the bidding phase or under construction.For each project,with the exception of the treat-ment plant expansion,TampaBayWater is usingthe traditional design-bid-build procurementprocess. The treatment plant expansion is usinga design-build/open book process with the ex-

isting operating company as the design-buildcontractor.The SurfaceWater SystemExpansionprojects are expected to cost nearly $200million,and per the co-funding agreement, all the proj-ects must be completed by December 2011.

Tampa Bypass CanalPump Station Expansion

The Tampa Bypass Canal Pump Station

Figure 3: Aerial View, Tampa Bypass Canal Pump Station Expansion Site

Figure 4: Coffer Cell Sheet PilingInstallation for the Tampa Bypass CanalPump Station Expansion

Figure 5: System Operating Curves for the Expanded Tampa Bypass Canal Pump Station

Continued from page 40

(Figure 2) is used to withdraw raw surfacewater from the Tampa Bypass Canal and is lo-cated in Hillsborough County. The existing fa-cility became operational in 2002.

The original water-use permit issued bythe water management district allowed vari-able withdrawals based on the flow rate in thecanal and the Hillsborough River on the pre-vious day, with amaximumwithdrawal rate of259 mgd. The existing facility was installedwith a maximum withdrawal capacity of 138mgd, currently accomplished with four single-stage 30.4-inch impeller vertical can pumpsdriven by 600-horsepower (hp) motors. Allfour motors are constant speed.

The current expansion project will in-crease the maximum withdrawal capacity tothe water-use permit limit of 259 mgd fromthe Lower Pool, the Middle Pool, or a combi-nation of the two. In 2007, the SouthwestWater Management District issued a renewedwater use permit for the facilitythat retained the maximum with-drawal limit, but altered the crite-ria for withdrawal quantities to bebased on minimum water level el-evations in the Lower and MiddlePools. The full scope of the TampaBypass Canal Pump Station ex-pansion project includes the fol-lowing elements:� New pump building� New electrical building� One 1750 kW/4160 V standby

generator (pre-purchased)� One above-ground fuel storage tank (pre-

purchased)� Four new vertical turbine pumps with 800-

hp motors� Four new variable frequency drives� Modification of four existing pumps and

motors, including new 800-hp motors� Suction and discharge headermodifications� Four additional intake screens

Figure 3 shows an aerial view of the con-struction site. The new pump and electricalbuildings are being constructed next to the ex-isting buildings in a mirror-image configura-tion. The auxiliary power facilities will belocated between the two pump buildings andare sized to provide 66mgd of capacity. Figure4 shows 65-foot sections of sheet piling beinginstalled to form the coffer cell that will sur-round the four new pump cans.

Several alternatives for the expansion

were examined. The selected alternative in-volves modifying the four existing pumps toincrease the impeller size from 30.4 to 32.74inches and adding four matching pumps, for atotal of eight pumps with 800-hp drive mo-tors.

Figure 5 shows the pump and systemcurves for the expanded facility. It can be seenthat the 259-mgd goal is met at 110 feet ofhead. Actual production will depend on sys-tem conditions, including water elevation inthe raw water storage tanks at the treatmentplant site. The production range, dependingon hydraulic conditions, is 243 to 277 mgd.

The design engineer for the Tampa By-pass Canal Pump Station Expansion project isMWH. Advertisement of the constructioncontract for the project occurred in June 2008.Bids were supplied by six contractors and wereopened publicly in July 2008.

The Tampa BayWater Board of Directorsawarded the construction contract to EncoreConstruction on August 18, 2008, in theamount of $16,960,000. Notice-to-proceedwas issued on September 2, 2008. Substantialand final completion are scheduled for Janu-ary 2011 and May 2011, respectively.

High ServicePump Station Expansion

The High Service Pump Station (Figure6) is located at Tampa Bay Water’s RegionalFacilities Site in Hillsborough County. The fa-cility includes three 7.5-million-gallon storagetanks where treated surface water and desali-nated water are blended before being pumpedinto Tampa Bay Water’s Regional System fordelivery to the member governments. The ca-pacity of the existing facility is 120 mgd.

The pump station currently consists offive horizontal split-case centrifugal pumps

FLORIDA WATER RESOURCES JOURNAL • OCTOBER 2009 • 43

Figure 6: High Service Pump Station

Figure 7: High Service PumpStation Operational Modes


with 2,000-hp motors. Four of the five pumpshave variable frequency drives. The expandedfacility will have a capacity of 135 mgd. Thescope of the High Service Pump Station ex-pansion project includes the following ele-ments:� New horizontal split-case pump in position

six with 2,000-hp motor and variable fre-quency drive

� New variable frequency drive to operate ex-isting pump in position five

� One 2500 kW/13.2 kV standby generatorand one 300 kW/480 V standby generator(pre-purchased), in addition to existing2250 kW unit

� Two above-ground fuel storage tanks (pre-purchased)

� Large diameter yard piping to bring freechlorine effluent from SurfaceWater Treat-ment Plant and Desalination Plant to com-mon point for new ammonia dosing station

� New chlorine storage, feed and dosing fa-cilities

� Modified ammonia storage, feed and dos-ing facilitiesThere are two possible modes of opera-

tion for the High Service Pump Station thatcan be seen in Figure 7. The current mode ofoperation is the “bypass”mode in which waterfrom the High Service Pump Station bypassesthe Cypress Creek Pump Station in PascoCounty. In this mode, both pump stations op-erate in a pressure-controlled scenario.

When the system expansions are com-plete, Tampa BayWater plans to operate in the“re-pump” mode in which water from theHigh Service Pump Station will be deliveredto a ground storage tank, and then will feedthe suction side of the Cypress Creek PumpStation. In this mode, the High Service PumpStation will be operated in a flow-controlledscenario and the Cypress Creek Pump Stationwill be operated in a pressure-controlled sce-nario.

Advantages of the re-pump scenario in-clude power costs savings and increased op-erational reliability because of the hydraulicdisconnection between the two large pumpstations. Set-point conflicts are a concern, es-pecially given the higher flows associatedwith the expansions and the large membergovernment deliveries that can occur fromthe transmission main between the twopump stations.

Tampa Bay Water must retain the abilityto operate in either bypass or re-pump modeto best manage planned and unplanned facil-

Figure 8: Expanded High Service Pump Station SystemOperating Curves for Bypass Mode

Figure 9: Expanded High Service Pump Station SystemOperating Curves for Repump Mode

Figure 10: Repump Station




ity outages.As such, alternatives were analyzedthat included both operational scenarios.

The selected alternative involves retro-fitting existing Unit 5 with a variable frequencydrive and adding a sixth pump with a variablefrequency drive.Adding the variable drives al-lows better service on the lower system curves.

Figure 8 indicates a production of 135mgd at 400 feet of head can be expected underaverage system conditions while operating inbypass mode. Figure 9 indicates a productionof 160mgd at 360 feet of head can be expectedunder average system conditions while oper-ating in re-pump mode.

The design engineer for the High ServicePump Station Expansion project is MWH.Construction was combined under a commonconstruction contract with the Repump Sta-tion Expansion project, which is described inthe following section of this article. The re-sulting contract is called the Regional Facili-ties Site Expansions.

Advertisement of the construction con-tract occurred in June 2008. Bids were sup-plied by three contractors and opened publiclyin July 2008.

The Tampa BayWater Board of Directorsawarded the construction contract to EncoreConstruction on August 18, 2008, in theamount of $15,100,000. The portion of thatamount associated with the High ServicePump Station Expansion is $8,155,600. No-tice-to-proceed was issued on September 2,2008. Substantial and final completion arescheduled for May 2010 and August 2010, re-spectively.

Repump Station Expansion

The Repump Station (Figure 10) is alsolocated in Hillsborough County at Tampa BayWater’s Regional Facilities Site. Quantitieswithdrawn from the Tampa Bypass CanalPump Station that are in excess of the influentrequired for the Surface Water TreatmentPlant are sent to Storage Tank No. 2 next to theRepump Station.

Water from Storage Tank No. 2 is drawninto the suction side of the Repump Stationand transferred to the 15-billion gallon Re-gional Reservoir located in southeastern Hills-borough County. Raw surface water from theRegional Reservoir is then available during dryconditions to feed the Surface Water Treat-ment Plant.

The current maximum capacity of theRepump Station is between 119 and 140 mgd,depending on the water elevation in the Re-gional Reservoir and whether or not the AlafiaRiver Pump Station is operating. Currently,the Repump Station consists of four 1,750-hpvertical turbine pumps with variable fre-


Figure 13: Off-streamReservoir Pump Station

Figure 12: System Operating Curves for the Expanded Repump Station

Figure 11: Repump Facility Operational Schematic

quency drives. Figure 11 shows a schematic ofthe Repump Station and the system in which itoperates.

Expansion of the Repump Station willallow transfer of higher flow rates to the Re-gional Reservoir, in conjunction with theSouth-Central Hillsborough Intertie BoosterPump Station (described below). The scope ofthe Repump Station expansion project in-cludes the following elements:� Two new vertical turbine pumps with

2,000-hp motors and variable frequencydrives

� Storage Tank No. 2 influent piping andvalve modifications

� Storage Tank No. 1 flow control and valvemodifications

� Reservoir return line flow control and by-pass pipingThemodifications will allow the two stor-

age tanks to be operated in series for flowsfrom the Tampa Bypass Canal or the RegionalReservoir. This will provide additional flexi-bility and amore uniform influent water qual-ity for the treatment plant.

The expanded Repump Station will oper-ate in series with the South-Central Hillsbor-ough Intertie Booster Pump Station. Figure 12shows the system/operational curves with theexpanded flow from the Repump Stationbeing boosted by the South-Central Hillsbor-ough Intertie Booster Pump Station. Opera-tion of the six three-stage vertical turbinepumps at 100-percent speed achieves a capac-ity of 180 mgd at 275 feet of head.

As described above, construction of theRepump Station Expansion is included in thesame contract as the High Service Pump Sta-tion Expansion. The design engineer for thisproject is also MWH. The component of thecontract amount associated with the RepumpStation Expansion is $6,944,400. The contrac-tual completion dates are the same as those forthe High Service Pump Station.

Off-StreamReservoir Pump Station

The Off-stream Reservoir Pump Station(Figure 13) will be a new facility that pumpsraw water from the Regional Reservoir to theSurface Water Treatment Plant. This new sta-tion will be located approximately 700 feetwest of the existing reservoir embankment.

The Off-stream Reservoir Pump Stationwill have the ability to send raw water to theSurface Water Treatment Plant as a stand-



Figure 14: Options for Delivering Water from the Reservoir to the Surface WaterTreatment Plant

Figure 15: South-Central Hillsborough Intertie Booster Pump Station

Figure 16: Regional Surface WaterTreatment Plant


alone facility, or it could be operated in serieswith the South-Central Hillsborough IntertieBooster Pump Station. Figure 14 shows theoptions for delivering water from the reservoirto the Surface Water Treatment Plant at vari-ous Reservoir depths and required flows.

The Off-stream Reservoir Pump Stationwill have four 400-hp vertical turbine pumpswith variable frequency drives. The pumpswill be mounted in pump suction cans be-cause the ground elevation at its location isapproximately 15 feet higher than the mini-mum hydraulic grade in the raw water trans-mission pipeline. The pump suction cans willextend as much as 30 to 35 feet below existinggrade. The full scope of the Offstream Reser-voir Pump Station includes the following ele-ments:

� Electrical building� Four vertical turbine pumps with 400-hp

motors� Four variable frequency drives� Piping and valve connections to existing 84-

inch transmission mainThe design engineer for the Off-stream

Reservoir Pump Station project is CDM. Ad-vertisement for the construction contract forthe project occurred in August 2009. Bids werescheduled to be opened in September 2009,and award of the construction contract by theTampa BayWater Board of Directors is sched-uled for October 19.

The engineer’s cost estimate for con-struction is $10.5 million. The constructioncompletion date for this project is scheduledfor mid-2011.

South-Central HillsboroughIntertie Booster Pump Station

The South-Central Hillsborough IntertieBooster Pump Station (Figure 15) will be anew facility that is intended to operate in serieswith the Facility Site Repump Station to trans-mit raw water to the reservoir. In addition, thestation will operate in series with the Off-Stream Reservoir Pump Station to increaseflows from the reservoir to the Surface WaterTreatment Plant (See Figure 14).

The project will include two 3,000-hphorizontal split case pumps with variable fre-quency drives. The station also includes aground storage tank that functions as a “feedtank” to supply water to the suction side of the


Figure 17:Existing Surface Water

Treatment Plant Schematic


pumps in the event of a sudden drop in suc-tion pressure. The full scope of the South-Cen-tral Hillsborough Intertie Booster PumpStation includes the following elements:� Pump building� Electrical building� 330,000 gallon ground storage tank� Two horizontal split-case pumps with

3,000-hp motors� Two variable frequency drives� Piping and valve connections to existing 72-

inch transmission mainThe design engineer is CDM, and the bid-

ding and construction schedule is the same asfor the Off-stream Reservoir Pump Station.The engineer’s estimate for construction is$12.6 million.

Regional SurfaceWaterTreatment Plant

The Surface Water Treatment Plant (Fig-

ures 16 and 17) treats raw water from theTampa Bypass Canal and Alafia River, as wellas raw water stored in the Regional Reservoir.The plant is being expanded through a“design-build construction manager at-risk” contractwithVeoliaWater NorthAmerica - South LLC.

Veolia, formerly US Filter, was the origi-nal constructor and has been the operator ofthe treatment plant since the project’s incep-tion. An amendment to Veolia’s existing con-tract was executed in April 2007 to cover theexpansion. Under the amendment, Veolia isdesigning, permitting, and constructing theexpansion and will continue to operate theplant.

The current plant has a rated capacity of72 mgd. The expanded plant will be able toproduce 99 mgd on a daily basis and will havea rated capacity of 120 mgd.

The Regional Surface Water TreatmentPlant expansion project includes two newcomplete treatment trains with capacities sim-ilar to the existing two trains. The following

facilities are being added:� Two sets of high-rate flocculation/sedimen-

tation/settling basins� Two ozone contactors� Six dual media filters with sand and granu-

lar activated carbon� Gravity thickener� Two backwash water clarifier units� Segregated clearwell to augment the exist-

ing smaller clearwell� Chlorine contact chamber and increased

transfer pumping capacity� Two belt filter presses and belt filter press

building for solids handling� Replacement of existing effluent line with a

larger diameter line� Auxiliary power for half of the treatment

trains (capacity of 66 mgd)� Expansion of existing chemical feed systems

The guaranteed maximum price pro-vided by Veolia for the expansion is$126,764,728.An owners allowance of $7 mil-lion was also approved, bringing the projectbudget to $133,764,728.

Construction costs are being paid basedon competitive procurement and an openbook approach. The major construction andequipment packages were required to be bidto ensure market competitive pricing for themajority of the overall project costs. The pri-mary installation contractor is Brasfield &Gorrie. This project is currently under con-struction (Figure 18) with anticipated startupby July 2010, and acceptance testing comple-tion by the end of December 2010.

Supply Increase

Because use of the surface water supplysystem is so dependent on stream flows andclimatic conditions, the Regional SurfaceWater Treatment Plant is not expected to op-erate at capacity at all times. As an example,the plant has a current rated capacity of 72mgd, but it produced an average of 42 mgd inwater year 2008 and is on track to produce andaverage of 33 mgd in water year 2009.

The lower production is 2009 is caused byextreme drought conditions and reservoir op-erational constraints that caused the plant to becompletely down frommid-March through theend of May. Up to 45 mgd of plant productionis budgeted for water year 2010. Once the Sur-face Water System Expansion is complete, andall components are operational, average pro-duction from the treatment plant is expected tobe 84 mgd during average rainfall years. ��


Figure 18: Surface Water TreatmentPlant Expansion Construction

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