Case Studies

UV System Key to Future Expansions at Indiana WWTP

When Plainfield, Ind., needed to double its permitted capacity from 2 million gal per day (mgd) to 4 mgd at its South wastewater treatment plant, it faced a dilemma. Plainfield is on the southwest edge of Indianapolis and part of one of the fastest growing counties in Indiana, with growth projections extending well into the future. Like most treatment plants, space is at a premium there, and compact design was needed not only for the current expansion—including the addition of a post-aeration structure—but also to preserve as much room as possible for projected future expansions.

Recharging With Reuse

The 55.5-million-gal-per-day (mgd) Southern Regional Wastewater Treatment Plant (SRWWTP) in Hollywood, Fla., treats wastewater from Hollywood and six neighboring municipalities in the southern region of Broward County. Florida’s outfall rule requires the city to begin a process to largely eliminate the use of its ocean outfall and implement 20.4 mgd of additional reuse water on an annual basis.

Florida County Aims for Full Usage of Reclaimed Water

In 2016, Hillsborough County Public Utilities initiated the first direct potable reuse pilot project in Florida. In its efforts to utilize 100% of its reclaimed water, the progressive utility created a successful program to effectively suspend surface water discharges.

Healing the Hudson

The Hudson River, in the Capital District of Albany, N.Y., is a popular recreational area for boating, swimming and fishing. Unfortunately, combined sewer overflows following storm events and snow melt from sewer systems dating back to the 1800s were causing increased fecal coliform counts, which, in turn, resulted in health alerts and limited access to the river.

Clear and Healthy

The Georgia Aquarium, located in the heart of Atlanta, opened its doors in 2005 as the world’s largest aquarium, with 100,000 freshwater and saltwater aquatic residents in 10 million gal of water. The aquarium houses more than 60 exhibits spread over six distinct galleries, with each gallery corresponding to a specific environment and theme.


Rapidly Resuming Recreation

The communities serviced by the Rensselaer County Sewer District, collectively known as the Albany Pool, have combined sewer systems (CSS) that bring storm water, sewage and industrial wastewater directly to the wastewater treatment facility. When a storm or snowmelt results in exceeded capacity, local waterways become contaminated, resulting in a significant environmental challenge—especially in a community where recreational swimming, boating and fishing are popular in warmer months.

CalPOP Culture

The American Canyon (Calif.) Wastewater Treatment Plant (WWTP) began operation in October 2002 with then-state-of-the-art secondary treatment that featured one of the nation’s first uses of tandem membrane bioreactor/UV disinfection in the process chain. As with many other early membrane bioreactor treatment plants, this facility had a number of design deficiencies, which became apparent over time as the equipment aged, the utility’s customer base expanded and more stringent environmental regulations were enacted.


Retrofit for the Future

A $250 million capital program by the Metropolitan Water District of Salt Lake & Sandy (MWDSLS) has equipped the wholesale water utility to produce improved water quality and to meet projected demand through and beyond 2025.


By 2025, Salt Lake City expects to gain additional 100,000 residents, and the City of Sandy expects to gain 30,000. The accelerating growth of the MWDSLS customer agencies, along with the need for system reliability and redundancy, spurred the proactive capital improvements.

Disinfection in the Desert

Located north of Phoenix, Lake Pleasant Regional Park serves as a large outdoor recreational hub for Arizona residents. The lake itself, the second largest reservoir in Arizona, is a place where people boat and swim, and it serves as a water resource for the 400,000 households within the municipal boundaries of Peoria.


Rio Grande Reclamation

The Rio Grande River and the two major aquifers in the El Paso, Texas, area had been dried up for decades when El Paso Water Utilities (EPWU) developed the Fred Hervey Water Reclamation Plant—the nation’s first full-scale wastewater reclamation plant to use tertiary treatment to restore wastewater to national and state potable water standards.


Teutonic Treatment

Infraserv Hoechst is a leading company for operating large-scale industrial and chemical production complexes. It is a complete service provider offering services such as purchasing, engineering and facility management, and it has a full supply of products such as compressed air, steam, cooling water, purified water, technical gases and energy.

Pulp Ozonation

SNIACE S.A. is a pulp mill located in Torrelavegas, Spain (near Santander), with an annual production capacity of 66,000 tons of dissolving pulp from Eucalyptus. Forty percent of the pulp is used in its own viscose plant, and the remaining 60% is sold to the market.

SNIACE’s cellulose is used to make various products, such as viscose fibers for the textile industry; acetate for the chemical industry; sanitary towels, insulators and cellulose film for industrial applications; and cloths and sponges for household use.

Reuse & Renewal

With diminished rainfall, a depleted aquifer basin, near-empty recharge ponds and an earthquake-vulnerable aqueduct system, the Santa Clara Valley Water District (SCVWD) in San Jose, Calif., required additional water supplies to maintain regional economic vitality for its growing community.


In the Ozone

Enactment of the Long Term 2 Enhanced Surface Water Treatment Rule and the Stage 2 Disinfectant and Disinfection Byproduct Rule (D/DBPR) will require both large and small drinking water utilities to reduce total organic carbon (TOC), cryptosporidium, and disinfection byproducts (DBPs) in the treated drinking water distributed to the public. Ozonation has helped prepare a North Carolina Water Treatment Plant (WTP) to comply with these federal drinking water regulations and overcome long-standing taste and odor problems of its raw water drawn from the B.

Getting Off the Ground

Clovis is a city with a population of around 97,000 in Fresno County, Calif. The city is 6.5 miles northeast of downtown Fresno. Until the early 1970s, groundwater was the sole water source for the residents of Clovis. Well water was used for irrigation and industrial use, as well as drinking water. As the population grew in Fresno County, ground water levels dropped and wells began drying up. To meet the growing water needs, the city of Fresno decided to recycle water being processed at its wastewater treatment facilities.


Hope for the Future

The city of Carmel, Ind., located north of Indianapolis, owns and operates Carmel Wastewater Treatment Plant (WWTP), which treats sanitary waste from Carmel, Clay Waste District and Westfield Utilities. When the plant became unable to meet the growing demands of the 70,000-person population area, the city decided to increase Carmel WWTP’s capacity to meet current and future water treatment demands.


A New Taste

Prairie du Sac, a village of 3,400 located in south central Wisconsin, began its journey to UV disinfection when it was selected as one of 14 communities in the state to participate in a $2.3-million, U.S. Environmental Protection Agency (EPA)-funded study focusing on the role of drinking water in childhood illnesses. The Marshfield Clinic Research Foundation in Marshfield, Wisc., conducted the Wisconsin Water and Health Trial for Enteric Risk.

Cheaper Is Not Always Better

Summerville, Ga., a small city in the northwestern part of the state and the seat of Chattanooga County, built its 2-mgd wastewater treatment plant in 1967. It was designed to handle the flow from a developing municipal collection system that now serves 1,860 connections.

Project Background