The Village of Waterbury (Vt.) Wastewater Treatment Plant (WWTP) is located on the Winooski River floodplain, which poses challenges from significant flooding during the spring runoff and storm seasons to strong algal blooms in late spring. During algal blooms, the plant encounters bright green lagoon effluent that is high in total suspended solids (TSS), resulting in treatment upsets and inconsistent permit compliance. The system is part of a sensitive mountain watershed that discharges into Lake Champlain.
A new ballasted biological treatment process helped the Allenstown, N.H. Wastewater Treatment Plant expand capacity in response to orders from state regulators who had placed a moratorium on new sewer hookups.
The lower cost of the new process enabled the plant to make the improvements in the first place, because ratepayers had voted down previous bonding proposals to expand the facility. The new technology also allows the plant to achieve complete nitrification.
Economic development has its price, and sometimes it calls for major upgrades to a community’s wastewater treatment facilities.
That was the case in Fort Dodge, Iowa. Expansion of new Cargill and CJ Bio America plants in the nearby Iowa Crossroads of Global Innovation industrial park—resulting in 300 new jobs—has required additional capacity and biochemical oxygen demand (BOD) and total Kjeldahl nitrogen (TKN) removal capabilities at the Fort Dodge Water Pollution Control Facility (FDWPCF).
Sturbridge, Mass., has historically suffered from periodic blooms of filamentous bacteria that have caused bulking in the secondary clarifiers of their three activated sludge package plants. The elevated clarifier solids loadings during high flow events have often caused excessive backwash cycle times of their sand filter, and occasional diversion of excess flow to a neighboring publicly owned treatment works.
A medical device manufacturer in the United States wanted to expand production capacity without exceeding discharge limits that could result in crippling financial penalties. A city mandate of 10% reduction in water consumption for industrial users challenged the plant’s desire to expand, as water discharged from its operations was already rapidly approaching discharge limits. Additionally, it wished to drastically reduce its raw water requirements and waste disposal cost of operation.
The Duckwall Pooley Fruit Co. is one of the largest fruit packagers in the Hood River Valley in Oregon, packing approximately 1.8 million bushels of pears annually. To improve its operations and lower its costs, the company implemented new measures to optimize the rinse water usage in the pear packaging line. After packaging the fruit, collected water is chlorinated for disinfection and treated with coconut shell based activated carbon for residual chlorine removal.
Facing aging infrastructure and more stringent drinking water regulations, the city of Pauls Valley, Okla. undertook a rigorous pilot testing program to establish design parameters for a new water treatment plant which would achieve compliance for turbidity, pathogen and organic removal.
The Concord Department of Public Works serves the needs of approximately 16,000 residents and local businesses. Prior to 2007, the town of Concord, Mass., operated under a National Pollutant Discharge Elimination System (NPDES) permit that allowed an interim seasonal phosphorus limit of 0.75 mg/L. But after the Massachusetts Department of Environmental Protection and the U.S.
A U.S. medical device manufacturer wanted to expand production capacity without exceeding discharge limits that could result in crippling financial penalties. It also wanted to drastically reduce raw water requirements and waste disposal costs. The plant was producing a 375-gal-per-minute (gpm) waste stream containing organic and inorganic manufacturing byproducts.
The town of Grand Junction, Iowa, uses a groundwater source to provide water to 850 people. The water quality from a 365-ft-deep well is generally good, with iron concentrations of about 0.3 mg/L and hardness of about 273 mg/L. In the early 1930s, the town installed a vertical pressure filtration system with a softener to treat the water. The filter media, however, eventually became completely clogged and stopped operating properly. Water quality became poor, and there were issues with maintenance of the distribution system. It was difficult to find parts to repair the equipment.
The city of Elkton, Md., located near the head of the Chesapeake Bay, was recently required to meet new stringent wastewater effluent discharge regulations to protect aquatic life in the bay. The city’s wastewater treatment plant was using fine bubble air diffusers, which did not provide consistent nitrification and sufficient denitrification to meet the new requirements.
Finding a Solution
The village of Bald Head Island is a picturesque community off the mouth of the Cape Fear River in coastal North Carolina with no cars and access only by ferry from the mainland. The village treats groundwater from a semi-confined aquifer via 16 production wells at depths from 55 to 65 ft below the surface. The well water is piped to a 200-gal-per-minute (gpm) water treatment facility where it is treated to remove dissolved contaminates using two reverse osmosis (RO) treatment units that produce 140 gpm at 70% recovery.
More than a decade after going online as the largest low-pressure membrane system in the world, the first in Wisconsin and the first direct membrane filtration process on Lake Michigan, the Kenosha Water Utility’s (KWU) 22-million-gal-per-day (mgd) microfiltration membrane plant can claim satisfaction as an early adopter of new technology. Hundreds of visitors from around the world have toured the facility.