The $12.1 million upgrade to the Sandwich, Illinois, wastewater treatment plant (WWTP) was officially completed on May 1, 2025. PENETRON ADMIX SB, a crystalline waterproofing admixture, was specified to protect the reinforced concrete structures from deterioration resulting from constant exposure to effluent.
ORLANDO, Fla., Aug. 26, 2025 /PRNewswire-PRWeb/ -- The $12.1 million upgrade to the Sandwich, Illinois, wastewater treatment plant (WWTP) was officially completed on May 1, 2025. PENETRON ADMIX SB, a crystalline waterproofing admixture, was specified to protect the reinforced concrete structures from deterioration resulting from constant exposure to effluent.
The City of Sandwich, Illinois, a town of almost 7,500 people, 60 miles west of Chicago, was faced with a mandate from the Illinois Environmental Protection Agency (IEPA) to reduce phosphorous discharge into nearby Harvey Creek from the municipality's WWTP. The deadline was extended by the IEPA from March 2023 to December 2024, and now, May 1st, 2025.
"The town's wastewater treatment plant was originally built in 2000 and treats up to 1.5 million gallons (MGD) of wastewater a day," adds Patrick O'Brien, Western Region Sales Manager for Penetron USA. "However, the facility needed upgrades to enhance the removal of nutrients, including phosphorus, from the effluent and ultimately improve water quality in Harvey Creek and further downstream."
The construction project included the addition of a phosphorus-removing chemical feed system, filters, oxidation ditch aerators, VFDs, raw sewage pumps, two aerobic biosolids sludge digesters, and upgrading of the existing aerobic digesters with new diffusers and blowers.
The durability of concrete structures in WWTPs depends primarily on protecting the imbedded steel reinforcement from corrosion by reducing the permeability of concrete to water, air, and chloride ions. Without an adequately robust waterproofing treatment, the overall aggressive environment of the effluent can quickly lead to concrete deterioration.
Grundy Redi-Mix, the project's ready-mix concrete supplier, specified PENETRON ADMIX SB, a crystalline waterproofing admixture, for the walls of the facility's new sludge digesters.
Once added to the concrete mix, PENETRON ADMIX SB-treated concrete is impermeable to the effluent, stopping water, chloride ions, sulfates, and other chemicals from entering the concrete, even under the constant exposure to the hydrostatic pressure encountered in a wastewater treatment plant.
"The ability of PENETRON ADMIX SB to permanently self-heal microcracks helps prevent moisture and corrosion-related damage from occurring over the service life of the facility's new concrete structures," adds Patrick O'Brien.
The Sandwich upgrade project achieved compliance with the 1.0 milligrams per liter (mg/L) and future 0.5 mg/L phosphorus NPDES permit limits – and also delivered various improvements that replaced aging equipment and reduced the facility's operation and maintenance costs.
The Penetron Group is a leading manufacturer of specialty construction products for concrete waterproofing, concrete repairs, and floor preparation systems. The Group operates through a global network, offering support to the design and construction community through its regional offices, representatives, and distribution channels.
For more information on Penetron waterproofing solutions, please visit penetron(dot)com or Facebook(dot)com/ThePenetronGroup, email CRDept(at)penetron(dot)com or contact the Corporate Relations Department at 631-941-9700.
Media Contact
Corporate Relations, The Penetron Group, 631-941-9700, [email protected], www.penetron.com
SOURCE The Penetron Group
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