Treatment Plant & Well Exploration
Water System Improvements
add capacity on existing site
Osceola County Rural Water System Constructs
Treatment Plant and Adds Ground Storage Reservoir
Osceola County Rural Water System
- Maintaining the use of existing facilities during the construction of the new water treatment plant on the same site
- Surface resistivity aquifer testing to efficiently pinpoint high capacity wells
- 2,400 gpm water treatment plant for iron and manganese removal
- 1 million-gallon glass-fused steel ground storage reservoir
- 750 kW standby generator
Osceola County Rural Water System (OCRWS) provides service to 3,200 customers in five counties of Northwest Iowa. OCRWS continues to see increasing water demands from ag and confinement livestock facilities, industrial users and municipalities. OCRWS maintains two water treatment plants that serve the North Phase and South Phase of the rural water system. During 2017, OCRWS experienced water demands that exceeded their South Phase Water Treatment Plant (WTP) capacity, which confirmed the need to move forward with expansion of the facility.
The existing South Phase WTP was constructed in the early 1980’s, with a self-contained aeration/detention/filtration system called an Aerelator®. The existing treatment equipment had reached the end of its useful life, and there was no way to rehab the existing equipment while maintaining treatment for the South Phase. Additionally, the existing WTP capacity was unable to meet OCRWS’s growing water demands, so OCRWS decided to construct a new South Phase WTP.
DGR Engineering (DGR) worked closely with OCRWS to design a new WTP to target iron and manganese removal from shallow groundwater source near the site. The new WTP was designed on the existing WTP site to minimize the project footprint and avoid additional land purchase. With the WTP location being highly visible just off IA Hwy. 10, OCRWS and DGR worked together to develop a design that not only met their water quality and capacity needs, but was also aesthetically pleasing. The new treatment process includes aeration, detention, and filtration using a gravity filter arrangement, and will increase OCRWS’s treatment capacity from 750 gpm to 2,400 gpm.
OCRWS also needed additional source water capacity to utilize the treatment capacity of the new WTP. DGR used a surface resistivity testing program to generate multiple snapshots of the aquifer depth and production capacity. Resistivity testing uses a line of electrical probes to quickly estimate soil characteristics, without the time and expense of test drilling. The testing provides a series of graphs like the one shown below. It allowed OCRWS to gather aquifer information on hundreds of acres of potential well sites with 3 days of field work and quickly identify the highest probability areas for high capacity wells. The results of the graphs were verified with test drilling, and two new well sites were identified in the thickest and most productive areas of the aquifer.
Increasing demands at the new WTP made additional on-site storage necessary. A 1 million-gallon glass-fused steel ground storage reservoir was constructed to accommodate these needs. The additional finished water storage on-site will also give OCRWS flexibility in how they choose to operate the facility.
The total construction cost of the new WTP project was $7.8 million, which was financed using a combination of Iowa State Revolving Fund (SRF) loan and private funding. The SRF funding package included a forgivable SRF loan for standby power generation. DGR also helped OCRWS navigate SRF’s American Iron and Steel requirements. The new improvements to South Phase water source will allow OCRWS to meet current and future water demands while providing their customers with reliable, high quality water.
- Electrical Power
DGR engineers helped L&O Power Cooperative improve communications on its electric transmission system using existing transmission lines, fiber and underground fiber line.
Rock Rapids, IA
Treatment Plant & Well Exploration
DGR Engineering worked closely with OCRWS to design a new Water Treatment Plant to target iron and manganese removal from a shallow groundwater source near the site.
Due to concerns with the age and condition of the structures, along with safety clearances to energized equipment and conductors, a project was undertaken to replace the old infrastructure with new underground lines and associated padmount equipment.
Redwood Falls, MN
Street & Utility Improvements
Morningside Avenue was reconstructed totaling approximately 1,300 linear feet. The project included new sanitary sewer, water main, storm sewer, fiber conduits, decorative street lighting, and 9-inch concrete paving with colored concrete sidewalks.
Sioux City, IA
Wastewater Treatment Facility
The new plant, rated for 5.3 million gallons per day (MGD) peak day, doubles the capacity of its predecessor.
Planning started with site plan design for the new facility to offer maximum exposure to traffic on Highway 75.
Rock Rapids, IA