What Is a Catch Basin?


A catch basin inlet collects excess water from streets, parking lots, golf courses and anywhere drainage is important. Precast concrete catch basins and inlets are an effective alternative to poured-in-place drainage structures.

Columbia Precast Products are built in a range of standard sizes. Basins are built to stand up to load requirements and will accommodate many different pipe sizes. Our products excel in areas where a high-flow capacity is required.

A top view of a catch basin

A catch basin is part of a storm-drain system designed to prevent flooding or the accumulation of standing water. The catch basin consists of a grate and a below-ground compartment. The grate sits flush with the ground. Water runs through the grate and into the compartment below. The structure may include a sump to handle sediment and debris. An outlet pipe drains the water.

A properly designed catch basin prevents water from collecting on roads, parking lots, playing fields and other surfaces. Catch basins are sometimes called storm drains because they prevent flooding from rain and melting snow.

How Many Catch Basins Are Required for Drainage?

The number of catch basins required depends on the flow rate of stormwater at peak times. Other considerations are the slope of the ground, average rainfall amounts and area of impermeable surface.

For example, a large parking lot in the wet climate of Portland, Oregon may require several catch basins. An engineer generally determines the most effective placement and design of a drainage system.

How Does a Catch Basin Handle Debris?

Catch basins hold water below an elbow or outlet pipe. Standing water in the basin may contribute to the settling of sediment. Oil floats to the top of the standing water. A catch basin can handle oil and grease if the water level is properly maintained.

A catch basin sump captures some solids during low water flow. The sump can’t capture or remove all particles. In general, larger particles are more easily contained by a sump. With regular maintenance, you can make the most of a catch basin’s ability to handle debris and pollution.

Catch basins must be installed properly to prevent standing water. An incorrectly installed basin leads to structural problems and could move a drainage problem from one spot to another.

How to Install a Catch Basin Inlet

These simplified instructions give an overview of the installation procedure. Installers should be skilled in construction and follow local specification requirements. They will need specialized equipment for lifting and placing the basin. Required tools may include a crane, ladder, backhoe, excavator, rigging, and grout or mastic.

Before installation, choose and prepare the surface. A basin should sit in the lowest part of a drainage field.

  1. Mark the area: Make the spot where the catch basin or basins will be installed. You can also mark where pipes will be placed.
  2. Excavation: Contact power companies to locate buried utilities. Dig to the proper depth for the basin.
  3. Bedding: Use gravel or sand to build a base for the basin. The base must be firm and compacted to prevent settling of the heavy basins. It is recommended that you follow your local specifications for depth and compaction.
  4. Clearance: Remove large rocks or other materials to create a minimum clearance of 3 inches around the basin.
  5. Installation: Install each piece of the precast product separately. Bracing, grout, or mastic strips may be required. Check the alignment of the piece before adding the next piece.
  6. Place the lid: After the basin is in installed, place the lid with inlet grate on top.
  7. Backfill: Finish the installation by backfilling.

How Are Catch Basins Maintained?

You can improve the effectiveness of a drainage system by frequent cleaning and maintenance. Regular cleaning is particularly important for drainage at industrial facilities. Sweeping reduces the amount of debris and pollutants flowing from the catch basin. An insert, such as oil absorbing strips, will collect more sediment. If you install an insert, you’ll need to clean the basin more frequently since the insert filter more sediment.

Precast Concrete Catch Basins in Vancouver, Washington

Precast concrete catch basins are effective for stormwater drainage in the Pacific Northwest. Our products offer the strength essential for construction in Oregon and Washington. We can customize precast concrete products for just about any project, from parking lots to soccer fields.

Contact us for more information on our products and services.