Storm Intake Stabilization and Pipe Sealing in Galesburg, IL

Project Background

In the summer of 2024, the City of Galesburg contacted Concrete PolyFix to address severe erosion and structural instability in multiple storm intakes. One intake had developed a sinkhole behind it due to gaps in the precast structure that allowed water infiltration, weakening the surrounding soil. Another intake had caused a significant void beneath the street due to improper water collection, which jeopardized the integrity of the roadway. City officials needed an effective solution to prevent further erosion and sinking, ensuring the long-term stability of their stormwater infrastructure.

Scope of Work

Concrete PolyFix was tasked with:

• Stabilizing the Roadway and Soil:
  • Void filling and soil stabilization behind storm intakes to prevent erosion and sinkhole formation.
  • Strengthening the roadway to mitigate the risk of collapse due to voids forming under the street.
• Sealing Storm Intake Pipes:
  • Ensuring that pipes adjoining the bottom of the intakes were watertight to maintain proper water flow and prevent further soil erosion.

Challenges

The project presented several key challenges:

• Safety Risks: The presence of sinkholes behind storm intakes posed a direct hazard to pedestrians and homeowners.
• Structural Risks: Large voids beneath the street increased the potential for concrete collapse, requiring immediate intervention.
• Water Intrusion Issues: The existing storm intake structures were not watertight, allowing water to seep into surrounding soil and accelerate erosion.

Solutions

Concrete PolyFix implemented a multi-step approach using high-performance polyurethane injection technology:

1. Injection for Void Filling and Roadway Stabilization
   1. Technology Used: Dual-Component Expanding Polyurethane Foam
   2. Method:
      1. Injected under the street and around the storm intake to fill voids and reinforce the soil.
      2. The foam expanded to create a stable base, reducing the risk of further sinking or erosion.
      3. This solution provided immediate structural support to the roadway, preventing potential collapse.
2. Waterproofing and Pipe Sealing for Erosion Control
   1. Technology Used: Dual-Component Expanding Polyurethane Foam
   2. Method:
      1. Injected around pipes within the storm intake to create a watertight seal.
      2. This ensured proper water flow and prevented further soil erosion from uncontrolled seepage.
      3. The waterproofing barrier enhanced the long-term durability of the storm intake structure.
      4. Stabilized soil to prevent sinkhole recurring.

Results

Long-Term Value:

• Durability: The polyurethane solution provided a long-lasting fix, preventing further erosion, sinkholes, and ensuring the storm intakes remained structurally sound.
• Minimal Disruption: The non-invasive injection process allowed for rapid repairs, with 2 storm intakes completed per day, minimizing road closures and inconvenience to residents.

Cost Savings:

• Avoided Full Replacement Costs: The cost of fully tearing out and replacing storm intake boxes can reach up to $11,500 per intake. Instead, Concrete PolyFix’s polyurethane injection solution offered a cost-effective alternative:
• Structural stabilization and waterproofing: $2,500 – $2,800 per intake box.
• Soil stabilization and waterproofing: $1,400 – $1,600 per intake box.

Conclusion

Concrete PolyFix successfully stabilized and waterproofed Galesburg’s storm intakes, preventing further erosion and ensuring long-term infrastructure integrity. By implementing an efficient and cost-effective polyurethane injection process, the city avoided costly full replacements while securing a durable and reliable stormwater management system. This case study highlights Concrete PolyFix’s ability to deliver innovative stabilization solutions with minimal disruption and maximum efficiency.