Fitzpatrick, James

James Fitzpatrick is a speaker at WEFTEC 2026.

Titles from this speaker

Better Pathogen Removal by EHRT than Activated Sludge Alone

Abstract

Multiyear, side-by-side, full-scale studies at the Bay View Water Reclamation Plant in Toledo, Ohio demonstrate that leading-edge, non-biological enhanced high-rate treatment (EHRT) technologies provide equal or better reduction of pathogens and pollutants of concern from peak wet-weather flows as conventional activated sludge treatment. In particular, the EHRT train demonstrated statistically higher reductions of Campylobacter, Cryptosporidium and Giardia than the parallel activated sludge train. In many cases, such as densely populated urban areas, wet-weather flow capacity expansions with EHRT technologies are significantly less costly and more resilient than other alternatives. Wastewater, stormwater and water reclamation utilities should continue to consider EHRT alternatives as they develop and implement plans to control wet-weather flows and manage water quality.

SpeakerFitzpatrick, James

Presentation time

10:30:00

10:50:00

Session time

10:30:00

11:30:00

SessionKilling Me Softly: Disinfection for Pathogen Control

Session number522

TopicDisinfection and Public Health, Research and Innovation, Water Reuse and Reclamation

Author(s)

K. GordonJ. FitzpatrickR. IvesJ.B. RoseJ. FitzpatrickC. McGibbeny

Author(s)K. Gordon1; J. Fitzpatrick1; R. Ives2; J.B. Rose3; J. Fitzpatrick1; C. McGibbeny4;

Author affiliation(s)Black & Veatch, MO1; Michigan State University, MI2; Michigan State University3; City of Toledo Div of Water Reclamation, OH4

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2020

DOI10.2175/193864718825157533

Volume / Issue

Content sourceWEFTEC

Word count10

Description: Early Adopters Prove Resiliency of Auxiliary Treatment Strategy and Effectiveness of...

Early Adopters Prove Resiliency of Auxiliary Treatment Strategy and Effectiveness of Latest Generation of Multi-Purpose Filtration

Abstract

BACKGROUND
Many utilities face increasing challenges from (A) high wet-weather flows and (B) stringent effluent limits. Some also aspire to (C) decarbonize and increase resource recovery. Filtration was previously considered feasible only for tertiary polishing (B); however, filter technologies have evolved to address (A) and (C). These can improve performance and resiliency as POTWs mitigate climate change, aging infrastructure, and growing populations. Previous generation pile cloth filters have successfully helped solve (A) and (B) for over 10 years (Fitzpatrick et al, 2018). Adaptations emerging for (C) enhance the capture of influent carbonaceous materials to recover bioenergy, bioplastics feedstock, or other renewable resources and lower downstream energy demands (Hengel-Prom et al, 2022). Several facilities in the US and UK have operated primary filters since circa 2017, more are being installed/designed, and dozens have piloted successfully. The latest generation technologies further increase the viability of multi-purpose applications.

Regulatory policies on (A) vary nationwide and around the world. Within the United States Eighth Circuit Court's jurisdiction, USEPA honors the Court's 2013 decision upholding blending and auxiliary enhanced high-rate treatment (EHRT) technologies, such as pile cloth filters (Iowa League of Cities v EPA). Utilities outside the Eighth Circuit have regulatory precedence for case-by-case permitting, such as USEPA's 1994 CSO Control Policy and NPDES permits for other EHRT facilities outside of the Eighth Circuit. Efforts continue for consistent federal policy that more clearly allows pile cloth filters and other EHRT technologies for auxiliary wet-weather treatment nationwide.

METHODS AND RESULTS
Little Rock Water Reclamation Authority (LRWRA) and Johnson County Wastewater (JCW) successfully overcame these challenges, inside and outside the Eighth Circuit, respectively. Both utilities began operating multi-purpose pile cloth filter facilities in 2021 following comprehensive evaluations, applied research, onsite piloting, design, value engineering and construction. The alternatives evaluations included triple-bottom-line assessments, reference facility visits, and onsite piloting of leading EHRT technologies (Szerwinski et al, 2023).

JCW saved $200M in construction costs with a multi-purpose filtration strategy compared to wet-weather flow storage and equalization. Design and CMAR collaboration saved an additional $40M in construction costs through 60% design value engineering for wet-weather treatment and nutrient removal. The multi-purpose filters are part of improvements that achieve annual average nutrient goals of TP<0.5mg/L and TN<10mg/L at an average design flow rate of 19mgd with peak wet-weather capacity up to 172mgd. A 115mgd AquaStorm MegaDisk filter facility provides direct filtration of coarse-screened influent during peak wet-weather flow events and is also used during normal flow conditions to enhance capture of phosphorus-bearing solids. This system is the largest capacity dual-purpose pile cloth disk filter facility in the US. Monitoring data demonstrate that the multi-purpose filter consistently achieves TSS < 5mg/L during normal conditions and < 20mg/L during peak wet-weather conditions.

LRWRA realized similar advantages as JCW at their Adams Field WRF. Improvements include (1) nitrification and denitrification retrofits and clarifier upgrades to the existing 36mgd activated sludge process and (2) new 58mgd multi-purpose filter, 94mgd UV disinfection expansion, and 94mgd effluent pump station. The filters used for auxiliary parallel wet-weather treatment are also used for effluent polishing during normal flows to improve effluent quality and downstream UV performance and O&M. The stormiest month was March 2023, when four wet-weather events required auxiliary treatment for 16 of 31 days. Effluent TSS and BOD remained at or below 10mg/L.

CONCLUSIONS AND RELEVANCE
Results from JCW and LRWRA agree favorably with reference facilities at over 40 POTWs nationwide and over 100 worldwide operating a variety of EHRT technologies for over 30 years. These data show that pile cloth filters and other EHRT technologies are consistently able to provide 'non-biological secondary treatment' of wet-weather flows, further supporting the US Eighth Circuit Court's 2013 decision and 2021 clarification upholding EHRT applications to wet-weather blending practices for both combined and separate sewer systems. Both facilities co-thicken and anaerobically digest carbon-bearing solids captured by the filters, thus these facilities' operations also add to the knowledgebase for emerging enhanced primary treatment applications aimed at increasing decarbonization and resource recovery.

This paper was presented at WEFTEC 2025, held September 27-October 1, 2025 in Chicago, Illinois.

Presentation time

15:30:00

16:00:00

Session time

15:30:00

17:00:00

SessionResiliency and Effectiveness of Wet Weather Flow Management and Treatment

Session locationMcCormick Place, Chicago, Illinois, USA

TopicLiquid Stream Treatment Technology - Preliminary, Primary, and Wet Weather Treatment

Author(s)

Fitzpatrick, James, Gupta, Vedansh, Hengel-Prom, Christine, Kadava, Anjana, Kerr, Tracy, Szerwinski, Alexander, Thompson, John, White, Nathan

Author(s)J. Fitzpatrick1, V. Gupta2, C. Hengel-Prom1, A. Kadava3, T. Kerr4, A. Szerwinski3, J. Thompson4, N. White1

Author affiliation(s)Black & Veatch1, Aqua Aerobic Systems Inc2, Johnson County Wastewater3, Little Rock Water Reclamation Authority4

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Sep 2025

DOI10.2175/193864718825160078

Volume / Issue

Content sourceWEFTEC

Word count17

Description: Improve Secondary Clarifier Performance with "Secret" Design...

Improve Secondary Clarifier Performance with "Secret" Design Resurrected from Yesteryear

Abstract

A clarifier inlet design conceived in the 1970s significantly improves hydrodynamic performance compared to most contemporary inlet and internal baffle configurations. This inlet design has improved operations and performance of peripheral-drive clarifiers in Great Britain and Germany since about 2005. The 1250-MLD (330-mgd) O’Brien Water Reclamation Plant (WRP) in Chicago, Illinois; the 470-MLD (124-mgd) Bolivar Wastewater Treatment Plant (WWTP) in Adelaide, Australia; and the 136-MLD (36-mgd) Adams Field Water Reclamation Facility (WRF) in Little Rock, Arkansas are among the first of a growing number of facilities to successfully adapt the design to center-column cage-driven mechanisms. Design considerations, operational benefits, and demonstration data from three-dimensional computational fluid dynamics (3-D CFD) modeling and full-scale field testing are discussed.

SpeakerFitzpatrick, James

Presentation time

13:00:00

13:20:00

Session time

13:00:00

14:00:00

SessionSettle Down! Case Studies of Secondary Clarifier Improvements

Session number604

TopicFacility Operations and Maintenance, Municipal Wastewater Treatment Design

Author(s)

J.L. BarnardL. DowningJ. FitzpatrickJ. FitzpatrickJ. ThompsonJ. TurnbullA. Kaufman

Author(s)J.L. Barnard1; L. Downing2; J. Fitzpatrick3; J. Fitzpatrick3; J. Thompson4; J. Turnbull5; A. Kaufman6;

Author affiliation(s)Black & Veatch, KS1; Black & Veatch, WI2; Black & Veatch, MO3; Little Rock Water Reclamation Authority, AR4; Black & Veatch, Surrey5; Hawkins-Weir Engineers, Inc., AR6

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2020

DOI10.2175/193864718825157569

Volume / Issue

Content sourceWEFTEC

Word count11

Pioneering Decarbonization and Resiliency with Pile Cloth Media Filtration

Abstract

[b]INTRODUCTION[/b] Wastewater utilities are facing increasing pressure from tighter nutrient regulations, more frequent extreme wet-weather events, rising energy costs, and limited site footprints, while also pursuing greater resource recovery and energy neutrality. Over the past 15 years, pile cloth media filtration (PCMF) has emerged as an effective alternative or complementary technology to conventional solutions for many of these issues. Initially developed for tertiary polishing, PCMF has demonstrated greater than 80% TSS removal and 45–65% BOD removal, while enabling carbon diversion, energy savings, and capacity expansion within a compact footprint. Today, early adopters are using PCMF for advanced primary treatment, dual-use wet- and dry-weather operation, and dedicated auxiliary wet-weather flow management. Figure 1 illustrates a typical layout of a PCMF replacing or supplementing primary clarifiers and managing peak wet weather flows with high-effluent quality. This presentation will showcase three full-scale WRRFs using PCMF in the following [b]innovative roles beyond traditional tertiary treatment[/b]: •Primary filtration, replacing conventional primary clarifiers; •Dual-use systems, providing treatment for both dry-weather flows and peak wet-weather events; and •Stormwater Adaptive Filtration Equipment (SAFE) system, managing peak stormwater/wet-weather flows in parallel with a biological treatment train. We will share data from these case studies and insights into the operation and performance of PCMF, highlighting how the technology enhances plant capacity, resiliency, and overall sustainability. [b]CASE STUDIES[/b] [b]Case Study 1: Cave Creek WRP (Phoenix, AZ) – Primary Filtration Ahead of MBR[/b] Increasing water demand, drought and climate uncertainty have driven the City of Phoenix to invest in Advanced Water Purification (AWP) and reuse to establish a sustainable, locally controlled water source to supplement its reliance on surface water from the Colorado, Salt, and Verde Rivers. As part of this effort, Phoenix is rehabilitating the Cave Creek Water Reclamation Plant (CCWRP), which was idled in 2008 due to a slowdown in projected demand. The upgraded CCWRP will initially produce Class A+ reclaimed water for non-potable reuse and groundwater recharge, with plans to deliver purified drinking water to more than 25,000 homes by 2028 (Harris, 2025). Key upgrades include installation of PCMF for advanced primary filtration (Figure 2), conversion of the BNR basin to a membrane bioreactor (MBR), and replacement of existing filters with reverse osmosis (RO) and UV advanced oxidation. Use of PCMF significantly reduces total suspended solids (TSS) and organic loading to the MBR, lowering aeration energy demand by an estimated 25%. The PCMF also eliminates the need for separate fine screening and is projected to increase biogas production by approximately 25%. Delivered through a CMAR approach with an estimated cost of $300 million, the project represents the first direct potable reuse (DPR) facility in Phoenix and only the second in Arizona. [b]Case Study 2: Adams Field WRF (Little Rock, AR) – Dual-use Filtration[/b] The Little Rock Water Reclamation Authority (LRWRA) began operating major improvements at its Adams Field WRF in 2021. Improvements included retrofits to the existing 36-MGD activated sludge process, construction of a 58-MGD PCMF multi-purpose filtration facility (Figure 3), expansion of UV disinfection, and new effluent pumping capacity. The multi-purpose filters provide high-rate auxiliary treatment during storm events and effluent polishing during dry-weather conditions. Data from March 2023 where the plant was in auxiliary treatment mode for 16 days of the month is shown in Figure 4 along with plant performance data. This dual-use strategy avoided expansion of the wet-weather equalization basin from 13 MG to 26 MG, saving more than $10 million in capital costs. The project was approved through an NPDES permit renewal with no objections from the USEPA, demonstrating regulatory acceptance of integrated, flexible treatment solutions (Fitzpatrick et al, 2018). [b]Case Study 3: Morro Bay, CA – SAFE Application[/b] The City of Morro Bay replaced its vulnerable coastal WWTP with a new advanced treatment facility to address flood risk and long-term water reliability. A design-build approach led to selection of a BNR-MBR process operating in parallel with a PCMF-based SAFE system for peak wet-weather flow management. Rather than constructing a 5-MG flow equalization basin, peak flows are directly treated through the SAFE system for marine discharge. This approach reduced the size of the BNR-MBR system by 30%, eliminated the equalization basin, and resulted in more than $7 million in construction savings. The facility is now the first MBR plant in California permitted for indirect potable reuse (Black & Veatch, 2025). [b]RELEVANCE[/b] These case studies demonstrate how PCMF has transitioned from a niche tertiary technology to a flexible platform capable of addressing multiple treatment objectives within a compact footprint. As utilities face increasing regulatory, climate, and financial pressures, technologies that provide primary treatment, wet-weather resiliency, and dual-use application offer significant value. The projects highlight how PCMF can support advanced water reuse, reduce capital costs, and enhance operational flexibility.

This paper was presented at WEFTEC 2026 in New Orleans, Louisiana.

Presentation time

08:30:00

09:00:00

Session time

8:30:00

10:00:00

SessionAdvanced Primary Treatment Pathways: High-rate Filtration and Sludge Process Integration

Session locationErnest N. Morial Convention Center

TopicFacility Operations and Maintenance, Municipal Wastewater Treatment Design

Author(s)

Gupta, Vedansh, Fitzpatrick, James, Mally, Andy, Bevington, Erick

Author(s)V. Gupta1, J. Fitzpatrick2, A. Mally2, E. Bevington2

Author affiliation(s)Aqua Aerobic Systems Inc, 1Black & Veatch, 2Black & Veatch Corporation (HQ), 2Black & Veatch, 2

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Sep 2026

DOI10.2175/193864718825160397

Volume / Issue

Content sourceWEFTEC

Word count10

Description: Two Years Operating World's Largest Capacity Facility of Latest Generation...

Two Years Operating World's Largest Capacity Facility of Latest Generation Wet-weather Disk Filters

Abstract

The recently expanded and upgraded Tomahawk Creek WWTF continues JCW’s success eliminating wet-weather overflows and complying with new nutrient limits. After comprehensive evaluations of source control, equalization, conveyance, and treatment alternatives, JCW implemented an auxiliary treatment strategy with dual-purpose filters as the most resilient, sustainable, and cost-effective alternative. This strategy initially saved JCW $200M in construction costs compared to storage and equalization alternatives. Design collaboration with a construction manager at risk (CMAR) saved another $40M in construction costs through value engineering studies at the 60% design stage that optimized site usage and technologies for auxiliary treatment and biological nutrient removal. The renewed WWTF started operating dualpurpose pile cloth disk filters in 2021 for tertiary treatment of flows up to 216 ML/d (57 mgd) and auxiliary treatment of wet-weather flows up to 435 ML/d (115 mgd) for a total peak flow capacity of 651 ML/d (172 mgd).

Renewal of the Tomahawk Creek Wastewater Treatment Facility is a major milestone in Johnson County Wastewater's Integrated Plan to identify, assess, and prioritize infrastructure initiatives and investments. Among its innovations, the updated facility uses an auxiliary treatment strategy with dual-purpose pile cloth disk filters that polishes effluent and cost-effectively treats peak wet-weather flows up to 651 ML/d (172 mgd) for year-round benefits to local streamways.

SpeakerFitzpatrick, James

Presentation time

16:00:00

16:30:00

Session time

15:30:00

17:00:00

SessionThinking Outside the Basin: Auxiliary Wet Weather Treatment

Session locationRoom S504a - Level 5

TopicIntermediate Level, Municipal Wastewater Treatment Design, Wet Weather

Author(s)

Fitzpatrick, Jim

Author(s)J. Fitzpatrick 1; A. Szerwinski 2 ; J. Dyson 3; G. Miller 4; A. Ruther 5; N. White 6; A. Szerwinski 2; J. Fitzpatrick 1;

Author affiliation(s)Black & Veatch 1; Johnson County Wastewater 2 ; Aqua-Aerobics 3; Black & Veatch 4; Black & Veatch 5; Black & Veatch 6; Johnson County Wastewater 2; Black & Veatch 1;

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2023

DOI10.2175/193864718825159050

Volume / Issue

Content sourceWEFTEC

Word count14