Chestertown, Maryland ph 1-800-638-6884

Greenwood, Delaware ph 302-349-5528

Gillespie Precast Plant 1 and Plant 2 achieve a score of 100% on the mandatory surprise NPCA annual audit. Read more



No it’s not glamorous, but when you need the job done right, go with a proven success. Throughout the world, groundwater and surface water quality depend on precast concrete manholes to successfully convey sewer and stormwater while maintaining water quality. Their water tightness, strength and design flexibility make them the obvious choice for the toughest jobs — no matter how dirty.

At Gillespie Precast we can provide a variety of manholes that meet your needs, with flow Channels for up to 96″ Manholes.

Benefits & Features

  • Watertight ASTM C 478, “Standard Specification for Precast Concrete Manhole Sections,” specifies the proper manufacture of quality, watertight precast concrete manholes. Standard watertight sealants and gaskets are available that are specially designed for use with precast concrete, making multipleseam precast concrete manholes very easy to construct. Vacuum testing is an easy means of verifying watertightness, either in the plant or in the field, as detailed in ASTM C 1244, “Test Method for Concrete Sewer Manholes by Negative Air Pressure (Vacuum) Test.”
  • Long-term maintenance-free conveyance of sewer and stormwater With a specific gravity of 2.40 and superior frictional resistance, precast concrete manholes resist buoyant forces better than all other manhole materials. Fiberglass has a specific gravity of 1.86 and HDPE has a specific gravity of 0.97, requiring the use of tie downs and ultimately increasing project costs. With the many advantages over alternative products, precast concrete manholes are clearly the material of choice for long-term maintenance-free conveyance of sewer and stormwater.