Looking for feedback on pro’s & con’s of Concrete VS Fibreglass sewer lift station wet wells
asked 17 May 2017 asked by SewerB (630 points)
When using fiberglass it is not suggested to bolt rails or pumps in bottom.
I've had fiberglass, concrete and enameled steel wet wells. The steel lasted about 25 years, the fiberglass about 20, and the concrete is 10 years old and showing no signs of age. HS2 creates the environment for breaking things down. Venting on the concrete will likely help it last longer as the vent was visibly 2 to 3 times larger than the older stations, I'm guessing we have learned something through the years. The concrete is coated on the inside, mastic between sections and any area not covered with the coating (much like a truck bed liner material) is touched up including seams, edges and lid. I'm very encouraged by it. The fiberglass wet well with fiberglass lid sections I have experience with breaks down due to UV and heat and once starts delaminating, fails quickly afterward. I've noted considerable corrosion between hardware and fiberglass, likely not stainless steel hardware like we use today, even outside the well. The steel wells were technology at the time in 1973 when they were installed but within 10 years starting showing signs of corrosion. Hinges on the doors finally rusted and failed, and the edges of the lid finally broke down requiring major overhaul and eventual replacement with concrete. I would chose concrete for longevity and length of service - the important thing being that all seams and surfaces being coated with the correct material and not having an easy way out besides venting the well. I'm far from a industry professional but I have an understanding of each as I worked in the same utility with all technologies for 15 years. We anticipate taking the last fiberglass station out of service in a year or two - it's currently 17 years old.
I would recommend the fiberglass. We have one of our 5 stations fiberglass and it doesn't corrode like our concrete wetwells. I guess it depends on the H2S level in your station. Grease seems to not build up on the walls as much either. -Rob
I have specified, installed and managed utility districts for more than 30 years and have found fiberglass an excellent choice. Like the other products, concrete, coated steel, etc. the quality of the product has continued to improved over the years. The ease of installation, integrity of the unit as well as the life cycle continues to make it my preference.
My recommendation is neither so it does not actually answer your direct question. HDPE is the black plastic pipe that is made in size ranges from near 0.5 inch to 63 inch. I have worked with this material in the past ranging greatly in applications. It is far superior to concrete, fiberglass, PVC, steel, stainless and others. It is not cheap for a reason but will last longer than most all components of any system. Contact me if you like.