The water supply for this city in the mid-west was sourced from wells with very high levels of hardness, sulfate and moderate levels of nitrate. Wigen supplied RO systems at two of the City’s WTPs to follow the existing greensand gravity filters for Fe and Mn removal, to improve the quality of water distributed to the City’s customers. Each RO system includes concentrate recovery RO units that allow recoveries of 80 – 90%.

TREATMENT SYSTEM INFORMATION:
Site 1:
-Maximum Permeate Flow: 1,580 gpm 
-Array: Skids 1 & 2: 20:10, 6M, Skid 3: 12:6M 

Site 2:
-Maximum Permeate Flow: 1,060 gpm 
-Array: Skids 1 & 2: 12:6, 6M, Skid 3: 8:6M

While looking into treatment options for meeting the new arsenic standard, this small community began also looking into technologies that could soften the well water as well as reduce sulfate and ammonia levels. When reverse osmosis was chosen as the best option to meet all treatment goals, Wigen was selected to provide the RO system.

TREATMENT SYSTEM INFORMATION:
Maximum Permeate Flow: 540 gpm
Array: 8:6:4, 6M

This City had an ageing package clarification/filtration system that had difficulty meeting the State filtered water turbidity limit of 0.3 NTU. The City decided to replace the existing plant with a 2 MGD universal ultrafiltration system provided by Wigen. The plant is located in a park in the Salt Lake City area and water is fed from a creek around 160ft above the plant and this head is used to drive the water through the auto-strainers and membrane modules.

TREATMENT SYSTEM INFORMATION:
Capacity: 3 x 1 MGD Trains (N+1)
Design Flux: 44.7 gfd

To help support burgeoning growth due to oil production in this region of North Dakota, ultrafiltration and reverse osmosis were chosen for a new water treatment plant to treat water sourced from the Missouri River. Treatment challenges included highly fluctuating turbidities and seasonal temperatures as well as hardness of around 250 mg/L as CaCO3 and TDS up to 500 mg/L. RO treats 50% of the UF filtrate to reduce the treated water hardness and TDS levels. A UF backwash recovery system allows an overall UF system recovery of over 99.5%.

TREATMENT SYSTEM INFORMATION:
UF System:
-5 primary trains each with a capacity of 1.5 MGD
-2 secondary trains each with a  capacity of 150 gpm
RO System:
-3 trains each with a capacity of  729 gpm
-Array: 17:9, 7M
-Design Recovery: 80%

This small community in North Dakota was challenged with rapid growth and increasing demand, while the existing conventional package filtration systems at its two water treatment plants were frequently exceeding the turbidity standards. Both systems were replaced by ultrafiltration systems provided by Wigen. Pretreatment with coagulation and plate settlers was provided for each facility to treat the feed water with flashy turbidities. Installed in 2011, these were the first large scale potable UF systems in the United States to use Toray modules. These systems were designed very conservatively to minimize maintenance and cleaning frequencies for this remote community.

TREATMENT SYSTEM INFORMATION:
Site 1: Capacity: 2 x 1 MGD Trains
Site 2: Capacity: 2 x 0.5 MGD Trains
Design Flux: 20 gfd

A County was forced to take a well out of service after arsenic levels exceeded the EPA’s 10 ppb limit, leading to water restrictions for the affected community. To restore this vital water source, the County implemented a treatment process using oxidation and coagulation followed by Greensand Plus pressure filtration to reduce arsenic levels. Wigen provided the chemical dosing and filtration equipment, along with a backwash recovery system, as the site lacked access to sewer for backwash disposal.

TREATMENT SYSTEM INFORMATION:
Design flow: 500 gpm
Filter sizing: 3 x 84” diameter vessels
Backwash recovery tank: 25,000 gallons