Across the Nation our manholes have become increasingly in need of repair. Cities and Towns across the United States are rehabilitating dozens or even hundreds of manholes each year. The type of rehabilitation required on the manhole is different in almost every scenario. Prior to performing the repair, you need to ask some basic questions that will help guide you to the best possible solution:

• What is the substrate condition? Its tensile strength? Is the concrete flaking off?
• What are the infiltration issues? (at the chimney, the Mainline Connections, or Joints)?
• What is the impact on the area? (noise, vibration, dust)
• What gases are coming from the manhole? (hydrogensulfide)?
• What are the material requirements (adhesion, abrasion)?
• What are the application conditions (dust, water, small spaces)?

Once we are able to determine the conditions of the manhole we can then discuss the types of rehabilitation methods that will work best.

Cementitious Manhole Relining

• Is probably the most common type of repair in the area.  Typically used when we see brick manholes or precast with concrete deterioration.  This method typically requires minimal surface preparation beyond high pressure cleaning.   We Typically only reline manholes with a Calcium Aluminate that contains fiberglass flakes.  This helps to reduce corrosion and increase structural integrity.  Manholes are lined using a spin cast machine or sprayed by hand from down in the manhole.  Thickness will vary depending on the job and the amount of deterioration from the manhole.

Manhole Grouting

• In situations where the manhole is in fair condition but has several leaks we would recommend Curtain Grouting.   By sealing the manhole with Acrylamide Grout you create an external barrier wall around the manhole protecting it from infiltration for years to come.  To view an example:   Click Here

Epoxy Manhole Relining

• Using epoxy is becoming used more and more in the industry for its attributes.  The material is great in areas of high concentrations of hydrogen sulfide or active infiltration into the manhole.  Epoxy can be hand applied or spray applied depending on the difficulty of the area.  Another factor in Epoxy relining is the structural integrity of the manhole.   Depending on the amount of cracks, voids, etc… We may see a cementitious backing installed prior to the final epoxy coating.

Various Manhole Repairs

• Raising Manholes – Manholes are often paved over and forgotten about. Eventually requiring the manhole chimneys to be raised.
• Frame & Cover Replacement.  With wear and tear manhole covers may break or become loose creating infiltration issues into the manhole.
• Manhole Steps.  Many manholes with severe deterioration will require new manhole rungs.
• Manhole Benches & Inverts.  This part of the manhole sees the most sewage.  Because of this they are often deteriorated and in need of cementitious repairs.