Recent Developments with Composite Manhole Covers Help Solve A Leading Cause of Water Pollution
Stormwater, floodwater, rising tidal waters, (etc.) that are meant to be drained into our natural waterways via storm systems will also flow into our sanitary system (I&I). Sanitary systems have limited capacities, and when the I&I – not requiring treatment – enters the sanitary system, volumes can exceed capacity. Consequently, pathogen-filled sewer water reverses, surcharges, and spills into the streets, and waterways (SSOs); this is a leading cause of water pollution amounting to 32 trillion gallons of pollution each year.
SSOs also cost cities millions each year from fines, unnecessary rain guards, high wastewater treatment costs, electricity for added pump-time operation, and capital costs on over-capacity plants.
The compression molding composite process reduces the potential for part-to-part dimensional variation compared to iron casting allowing for a closely mated cover-frame fit. And as a bonus, wastewater crews report that the composite assembly greatly improves odor retention.
Municipalities have also suffered opening traditional manhole covers stuck to the frames from debris and sometimes iron oxide particles. Sewer gas (H2S) corrodes iron covers in many collection systems, especially around lift stations, air release valves, and water treatment plants. Composite manhole covers are inherently corrosion-resistant.
Composite covers bring many other: safer ergonomics, faster install, theft prevention, data transmission, cosmetic options, encapsulation of RFIDs/sensors, sustainability, and environmental impact. Finally, with the new compression molding process, assemblies are now becoming affordable and available in weeks not months.