What size catch basin do I need?

9x9 for single downspout or small area. 12x12 for larger collection areas or multiple pipe connections.

How deep should a catch basin be?

12-18 inches typically. Deeper basins provide more sediment storage before cleaning is needed.

Catch BasinGenerating image…

Gutters & Drainage

Drainage

Budget: $15-$25 (basic 9x9 with grate) | Mid-range: $25-$50 (12x12 with adapters) | Premium: $50-$100 (large with sediment trap and multiple outlets)

Catch Basins: Yard Drain & Surface Water Collection Points (2026)

Prepared by Lumberama's Building Materials Team

|Last updated May 25, 2026|Sources & methodology

Catch basins are underground collection boxes with surface grates that capture yard surface water and route it to underground drain pipe. They serve as collection points in yard drainage systems, at the base of downspouts, and at low spots where water pools. Available in square and round configurations with various grate options.

Key Features

Square and round configurations; 9x9 and 12x12 residential sizes; Multiple grate styles and colors; Connects to 3" and 4" drain pipe; Sediment collection at bottom

Specifications

Sizes: 9x9"

12x12"

6" round | Material: HDPE plastic | Grate: flat

atrium

NDS green | Outlets: 3" and 4" pipe adapters | Depth: 12-18" | Flow: 15-50 GPM depending on size

Applications

Yard low spot drainage collection; Downspout connection to underground drain; Driveway edge water collection; Patio and walkway drainage; Pool deck drainage systems

Installation Overview

Dig hole at collection point, slightly larger than basin. Set basin on gravel base at proper height (grate flush with grade). Connect drain pipe to outlet adapter. Backfill around basin. Install grate. Ensure proper slope on outlet pipe toward discharge point.

Pros & Cons

Pros

✓ Effectively collects surface water; Connects to underground drain system; Prevents yard water pooling; Low-profile grate blends with landscape

Cons

✗ Requires digging and pipe installation; Grate can clog with debris; Must maintain proper grade; Sediment needs periodic cleaning

Top Brands

NDS

Fernco

Reln

Code Requirements

Must discharge to approved location per local codes. Cannot drain onto neighboring property. Must not connect to sanitary sewer. Proper slope required on discharge pipe.

Buying Tips

NDS is the industry standard for residential drainage products; Buy the catch basin with pipe adapters already fitted; Include a sediment bucket or trap insert for easy cleaning