A Guide to the Benefits of Fiberglass-Reinforced Polymer in Wastewater Environments

It was not that long ago that the structural components, grating, sludge flights, trash racks and odor containment covers—along with walkways, ladders, guardrails and other access structures—in water and wastewater facilities were frequent sources of maintenance headaches and safety concerns. In areas exposed to constant moisture, chemicals and harsh conditions, traditional materials often struggled to hold up. Steel rusted, wood swelled and warped, aluminum corroded and concrete cracked. Before long, safety was compromised, operations were interrupted and replacement was inevitable.

That narrative is changing. Fiberglass-reinforced polymer (FRP) is becoming a go-to choice in wastewater applications. Some of the benefits of FRP include:

1. Corrosion resistance: Water and wastewater operations are notoriously tough on materials. Between constant moisture, humidity, chemical exposure and harsh cleaning agents, traditional metals often cannot keep up without extensive protection. Even then, coatings can chip or degrade over time. FRP, on the other hand, is inherently resistant to corrosion. It does not rust or rot. It stands up to aggressive chemicals and saltwater. Unlike metal that weakens over time when exposed to moisture or corrosives, FRP maintains its structural integrity for decades. It can be a good fit for environments where reliability is critical and access for repairs can be difficult or dangerous.
2. Safety: In facilities where both moisture and electricity are present, safety becomes even more essential. Unlike metal, FRP is nonconductive, reducing the risk of electric shock. It also performs well in extreme temperatures, high humidity and environments requiring flame-retardant materials. When combined with slip-resistant surfaces and high-visibility coloring options, it supports a safer environment for everyone on-site.
3. Durability: One of the most compelling advantages of FRP is how well it holds up over time. It does not warp, crack, split or buckle under load. Even in freezing temperatures or high heat, it remains dimensionally stable. Despite being lightweight compared to steel, FRP delivers impressive strength, which is critical for load-bearing structures in demanding wastewater environments.
4. Maintenance and uptime: Paint touch-ups, rust removal and replacement parts are routine issues with metal, but this is not the case with FRP. Because color is integrated into the material itself (not applied on top), it will not fade, peel or flake. As a result, FRP does not require regular recoating, sanding or rust prevention. Less maintenance means fewer shutdowns and lower labor costs, which can add up to substantial savings over time.
5. Investment: While FRP may come with a higher upfront cost compared to traditional materials, its longevity and lower maintenance requirements often make it a cost-effective choice over the life of the structure.

FRP in Water & Wastewater Facilities

From clarifiers to chemical feed areas, FRP is used in a wide range of structural and safety applications throughout water treatment operations. Some of the most common uses include:

1. Grating: FRP grating, available in both molded and pultruded options, offers excellent slip resistance, chemical durability and ease of installation. Molded grating provides strength in two directions and is often preferred for corrosive environments, while pultruded grating delivers higher load capacity in one direction, making it ideal for longer spans. FRP grating is ideal for walkways, equipment access platforms, trench covers and areas where liquids and debris need to drain through. With multiple resin options available, it can be tailored to the specific chemical and loading needs of the facility.
2. Structural shapes and platforms: FRP beams, angles, channels and square tubes are used to fabricate everything from maintenance platforms and stairs to elevated walkways and safety railings. These shapes offer the strength of metal without weight or corrosion issues, and they are easy to cut and assemble on-site.
3. Sludge flights and components: In clarifier tanks, FRP sludge flights offer a durable and noncorrosive alternative to steel or wood. They can be fabricated with integral scraping lips and drilled or notched for easy integration with mechanical systems. Certain resin systems also offer certifications for use in drinking water applications.
4. Baffle panels and containment covers: For flow control, odor containment or process separation, FRP baffle panels offer a strong yet lightweight solution. These panels can be installed in a variety of ways—attached to beams, concrete walls or support columns—and they stand up to both chemical exposure and structural stress. In applications involving potable water, National Sanitation Foundation (NSF)-rated resin systems are available.
5. Ladders, guardrails, walkways and more: FRP access systems like ladders, walkways and guardrails are corrosion-resistant, easy to install and offer high visibility for enhanced safety. Walkways and ladders are designed with gritted surfaces and integrated color, reducing the risk of slips and eliminating the need for repainting or recoating in high-moisture environments.

Protecting Performance Outdoors: The Role of UV Resistance

While FRP is naturally tough against moisture and chemicals, extended ultraviolet (UV) exposure can lead to surface wear over time, including discoloration and fiber bloom. That is why certain industrial-grade FRP systems now incorporate a UV-resistant coating to protect against sun exposure.

This coating enhances the durability of FRP, maintains structural performance and helps preserve color integrity. It also maintains visual appeal and meets Occupational Safety and Health Administration (OSHA) visibility requirements with pigmented, OSHA-compliant safety yellow coloring built into the material. For outdoor or partially exposed installations, UV-resistant finishes help ensure the material performs, stays compliant and looks good for years to come.

Choosing the Right Grating Solution

Not all grating is created equal, especially in water and wastewater environments. When considering FRP grating for a facility, it is important to consider:

• Load requirements: Will it support equipment or just foot traffic?
• Chemical exposure: What substances will it encounter?
• Sun exposure: Is the application subject to UV rays?
• Slip resistance: Will it be exposed to water, oils or sludge?
• Open area and drainage: How much flow-through is needed?
• Maintenance access: Will it need to be removed or repositioned?
• Certifications and compliance: Will the material need to meet industry certifications or safety standards?

Because FRP is available in a wide range of resins, profiles and finishes, it can be engineered to meet almost any requirement. Working with a supplier who understands the demands of wastewater facilities ensures the right products are selected for performance, safety and compliance.