Noboru Togawa

Ph.D Student at the University of Alabama, Ph.D Student at the University of Alabama, expected graduation, spring, 2010expected graduation, spring, 2010

Master in Environmental Engineering at the Master in Environmental Engineering at the University of AlabamaUniversity of Alabama

Academic Back GroundAcademic Back Ground

Work ExprienceWork Exprience

Research / Teaching AssistantResearch / Teaching Assistant Hydraulic Facilities DesignerHydraulic Facilities Designer

HIGH-RATE STORMWATER HIGH-RATE STORMWATER TREATMENT DEVICETREATMENT DEVICE

Noboru TogawaNoboru Togawa

Robert PittRobert Pitt

Department of Civil, Construction, and Environmental EngineeringDepartment of Civil, Construction, and Environmental EngineeringUniversity of AlabamaUniversity of AlabamaTuscaloosa, AL 35487Tuscaloosa, AL 35487

February 2009February 2009

Dept. of Civil, Construction, and Dept. of Civil, Construction, and Environmental EngineeringEnvironmental EngineeringUniversity of Alabama, TuscaloosaUniversity of Alabama, Tuscaloosa

• Dept. founded in 1837 (5Dept. founded in 1837 (5thth oldest in US)oldest in US)

• More than 500 undergraduatesMore than 500 undergraduates• More than 100 graduate studentsMore than 100 graduate students• 21 primary faculty21 primary faculty

• Roughly 5 million in annual Roughly 5 million in annual research expendituresresearch expenditures

OverviewOverviewo Introduction and significance of the researchIntroduction and significance of the researcho HistoryHistoryo Up-FlowUp-FlowTMTM Proto-Type Filter Proto-Type Filtero Location and Size of the FilterLocation and Size of the Filtero Full Scale Up-Flow Filter ComponentsFull Scale Up-Flow Filter Componentso Installation of FilterInstallation of Filtero Treatment Flow rate RequirmentsTreatment Flow rate Requirmentso Controlled Flow TestControlled Flow Test

o SedimentSedimento MethodologyMethodologyo ResultResult

o Future Research SubjectFuture Research Subject

Introduction & SignificanceIntroduction & Significance

Many types of stormwater controls are available, but most Many types of stormwater controls are available, but most are relatively large or insufficient in their treatment are relatively large or insufficient in their treatment capacity.capacity.

Adequate treatment of runoff requires the removal of many Adequate treatment of runoff requires the removal of many types of pollutants as well as large amounts of debris and types of pollutants as well as large amounts of debris and floatable materials, over a wide range of flows.floatable materials, over a wide range of flows.

Traditional downflow filters, which can provide high levels Traditional downflow filters, which can provide high levels of treatment, can quickly clog, reducing their treatment flow of treatment, can quickly clog, reducing their treatment flow rate and overall treatment capacity. They also usually rate and overall treatment capacity. They also usually operate at a low treatment flow rate requiring a large area to operate at a low treatment flow rate requiring a large area to treat substantial portions of the runoff from a site. treat substantial portions of the runoff from a site.

HistoryHistory This stormwater filtration device was developed by This stormwater filtration device was developed by

engineers at the University of Alabama through a engineers at the University of Alabama through a Small Business Innovative Research (SBIR) grant Small Business Innovative Research (SBIR) grant from the U.S. Environmental Protection Agency.from the U.S. Environmental Protection Agency.

Proto-Type Up-Flow FilterProto-Type Up-Flow Filter

Installed to about 0.9ac Installed to about 0.9ac parking lot.parking lot.

About 90% of volume About 90% of volume reduction with 10% bypass.reduction with 10% bypass.

Maximum filtration rates of Maximum filtration rates of about 25 gal/min.about 25 gal/min.

Up-FlowUp-FlowTMTM Proto-Type Filter Proto-Type Filter

Sump can collect the heavy Sump can collect the heavy debrisdebris

Small objects are filtered Small objects are filtered by Screen and Mediaby Screen and Media

During prototype field During prototype field tests, measured:tests, measured: 68-94% sediment 68-94% sediment

removalremoval 70-90% pollutant 70-90% pollutant

reductionreduction

Full Scale Up-Flow Filter ComponentsFull Scale Up-Flow Filter Components

Buoyant trash is captured by flotation in the chamber and retained by the floatables baffle during high-flow bypassing

Coarse solids and debris are removed by sedimentation and settle into the sump Capture of intermediate solids by sedimentation in sump resulting from controlled

discharge rates Neutrally buoyant materials are screened out by the angled screens Fine solids are captured in the filtration media Dissolved pollutants are removed by sorption and ion-exchange in the media

Location and Size of FilterLocation and Size of Filter A 7-foot tall 4-foot diameter standard inlet containing A 7-foot tall 4-foot diameter standard inlet containing

a six module.a six module. Installed at the Riverwalk parking lot near the Bama Installed at the Riverwalk parking lot near the Bama

Belle on the Black Warrior River in Tuscaloosa, Belle on the Black Warrior River in Tuscaloosa, Alabama. Alabama.

Land UseArea (ft2)

Area (acre)

% of Land Use

Parking Area 11,800 0.27 30.5

Other Paved 1,300 0.03 3.4

Side Walks 2,100 0.05 5.4

Entrance Road 10,990 0.25 28. 5

Green Space 12,400 0.29 32.2

Total 38,610 0.89 100.0

Installation of the FilterInstallation of the Filter

Treatment Flow rate RequirementsTreatment Flow rate Requirements

Treatment flow rate requirements for typical southeastern US Treatment flow rate requirements for typical southeastern US conditions (Atlanta, GA), based on continuous simulations conditions (Atlanta, GA), based on continuous simulations

(Pitt and Khambhammettu 2006) (Pitt and Khambhammettu 2006)

The 100 gal/min for the test site is expected to treat about 90 percent of the annual flow for a typical rain year, with about 10 percent of the annual flow bypassing filtration.

Controlled Flow TestControlled Flow Test The water flow rate was measured by measuring The water flow rate was measured by measuring

the time needed to fill a measured volume as well the time needed to fill a measured volume as well as by the flow sensor.as by the flow sensor.

Controlled Test SedimentsControlled Test Sediments The test sediment in the stormwater stimulant used a The test sediment in the stormwater stimulant used a

mixture Sil-Co-Sil 250, Sil-Co-Sil 106 (both from U.S. mixture Sil-Co-Sil 250, Sil-Co-Sil 106 (both from U.S. Silica Co.), and coarse and fine concrete sands. The Silica Co.), and coarse and fine concrete sands. The mixture was made by mixing the four components with mixture was made by mixing the four components with different ratios to obtain a relatively even particle size different ratios to obtain a relatively even particle size distribution representing the complete range from distribution representing the complete range from about 20 to 2,000μm. about 20 to 2,000μm.

Sediment mixture was manually and consistently added to the influent water over the 30 minute test period.

Test Methodology for Controlled TestTest Methodology for Controlled Test

Flow rate measured averages of 24gal/min, Flow rate measured averages of 24gal/min, 50gal/min & 100gal/min.50gal/min & 100gal/min.

Each experiment conducted over 30 minutes.Each experiment conducted over 30 minutes. River water is used as the “inflow” water.River water is used as the “inflow” water. Effluent samples collected using a dipper grab Effluent samples collected using a dipper grab

sampler every 1 minute.sampler every 1 minute. During these tests, four different influent During these tests, four different influent

sediment concentrations were tested: 50 mg/L, sediment concentrations were tested: 50 mg/L, 100 mg/L, 250 mg/L, and 500 mg/L.100 mg/L, 250 mg/L, and 500 mg/L.

Initial Controlled Test ResultInitial Controlled Test Result

Controlled tests can measure the filter Controlled tests can measure the filter behavior under known conditions. Mixtures of behavior under known conditions. Mixtures of ground silica available from U.S.Silica Co. ground silica available from U.S.Silica Co. were used for these initial tests, reflecting filter were used for these initial tests, reflecting filter performance for a variety of particle sizes. performance for a variety of particle sizes.

Result SummaryResult Summary25 gallon/min Flow Rate and 100 mg/L Concentration

Particle Size (μm)

Average Influent Concentration

(mg/L)

Average Effluent Concentration

(mg/L)

Average Reduction

(%)

< 0.45 220 160 27

0.45 to 3 5.2 1.1 78

3 to 12 19 11 38

12 to 30 26 8.3 68

30 to 120 16 1.3 92

120 to 1180 28 0.18 99

> 1180 5.7 0 100

sum >0.45 μm 99 21.9 78

Result Summary cont.Result Summary cont.25 gallon/min Flow Rate and 500 mg/L Concentration

Particle Size (μm)

Average Influent Concentration

(mg/L)

Average Effluent

Concentration (mg/L)

Average Reduction

(%)

< 0.45 240 120 49

0.45 to 3 26 3.2 88

3 to 12 92 32 65

12 to 30 130 28 79

30 to 120 81 3.9 95

120 to 1180 142 0.55 100

> 1180 30 0 100

sum >0.45 μm 500 67.7 86

Future Research SubjectFuture Research Subject Additional controlled flow tests are being Additional controlled flow tests are being

conducted using different flow rates and with conducted using different flow rates and with different mediadifferent media

Pollutant removal will be measured during Pollutant removal will be measured during actual storm eventsactual storm events

AcknowledgementsAcknowledgements

My advisor Dr. Robert PittMy advisor Dr. Robert Pitt

Funding provided by:Funding provided by: Hydro International, Portland, MEHydro International, Portland, ME Graduate Student Research Graduate Student Research

Program, AL Commission Program, AL Commission

on Higher Educationon Higher Education Small Business Innovative Small Business Innovative

Research program, US EPAResearch program, US EPA

References Describing Earlier TestsReferences Describing Earlier Tests Pitt, R. and Khambhammettu, U. (2006). Pitt, R. and Khambhammettu, U. (2006). Field Verification Report for the Up-Field Verification Report for the Up-

FloFloTMTM Filter Filter.. Small Business Innovative Research, Phase 2 (SBIR2) Report Small Business Innovative Research, Phase 2 (SBIR2) Report. U.S. . U.S. Environmental Protection Agency, Edison, NJ. 275 pages. March 2006.Environmental Protection Agency, Edison, NJ. 275 pages. March 2006.

Pitt, R., R. Andoh, S.E. Clark. “Laboratory and field tests of the Up-FloPitt, R., R. Andoh, S.E. Clark. “Laboratory and field tests of the Up-FloTMTM Filter,” Filter,” 1111thth International Conference in Urban Drainage International Conference in Urban Drainage, Edinburgh, Scotland, August , Edinburgh, Scotland, August 31 to Sept. 5, 2008.31 to Sept. 5, 2008.

Khambhammettu, U., S.E. Clark, R. Pitt. “Protocols for quantifying solids Khambhammettu, U., S.E. Clark, R. Pitt. “Protocols for quantifying solids removal performance during controlled testing of manufactured treatment removal performance during controlled testing of manufactured treatment devices.” Presented at the devices.” Presented at the World Environmental and Water Resources World Environmental and Water Resources Congress 2007Congress 2007. ASCE/EWRI, Tampa, FL, May 15 – 19, 2007.. ASCE/EWRI, Tampa, FL, May 15 – 19, 2007.

Pratap, M.R., U. Khambhammettu, S.E. Clark, R. Pitt. “Stormwater polishing: Pratap, M.R., U. Khambhammettu, S.E. Clark, R. Pitt. “Stormwater polishing: Upflow vs. downflow filters.” Presented at the Upflow vs. downflow filters.” Presented at the World Environmental and World Environmental and Water Resources Congress 2007Water Resources Congress 2007. ASCE/EWRI, Tampa, FL, May 15 – 19, 2007.. ASCE/EWRI, Tampa, FL, May 15 – 19, 2007.

Andoh, R., R. Pitt, and L. Glennon. “Upflow filtration system for stormwater Andoh, R., R. Pitt, and L. Glennon. “Upflow filtration system for stormwater treatment.” Presented at the treatment.” Presented at the 2007 South Pacific Stormwater Conference2007 South Pacific Stormwater Conference. New . New Zealand Water and Waste Association. Auckland, New Zealand May 16 – 18, Zealand Water and Waste Association. Auckland, New Zealand May 16 – 18, 2006.2006.

Thank youThank you