a division of Gustavo Preston Company

Tech Talk – Fiberglass Basins Covers, Hatches, and Curbframes

Fiberglass Ejector Basins 

Sewage or sump pumps are mounted inside a basin to remove liquid once it reaches a designated level in the basin.

The size of the basin is often dictated by the allowable space in the location. An additional consideration is the pump manufacturers minimum allowable dwell time. The dwell time is determined by dividing the pumps flowrate by the volume between the lead and stop levels.

Basins are available in fiberglass, poured concrete or pre-cast concrete. Each basin type has it’s advantages.
Fiberglass basin’s are available for purchase in a variety of sizes, shapes and configurations. Fiberglass basin’s are available in sections to allow access to restricted locations. They are also offered with “double walls” to provide a chamber to monitor leakage from the inner basin. They can be purchased with adjacent settling basins to allow solids to “settle out”. Finally, extensions mounted above the basin can be used as spacers or “valve boxes” to house isolation and check valves. These valve boxes can avoid damage to or meddling of the valves during operation.
Fiberglass basins can be provided with cup, cement or floor flanges. Cement flanges are an additional flange (Figure 1) to retain the basin when set in place to prevent hydraulic pressure under the basin from displacing it upward. Floor flanges are mounted on the bottom of the basin to prevent the basin from tipping by providing lateral support. Cup flanges allow flush mounting of the cover within a rim in the basin. Lifting brackets mounted on the side of the basin allow shipping and placement. Covers are mounted via equally spaced tapped holes in to the top of the basin.