When stormwater floods playgrounds, playing fields, parking lots, and shopping plazas, it indicates the excess water can’t properly drain. Without a fix, it can lead to slippery mildew, sink holes, and asphalt erosion which can quickly turn into safety hazards and costly property damage. Here’s how to take care of it. Capture heavy stormwater flows with the 18 in. Square Catch Basin Drain and direct it away to drain pipe for proper release downstream. The large catch basin has two openings to connect to 3 in., 4 in., 6 in., and 8 in. drain pipes with appropriate outlet adapters (sold separately). Made of high-density polyethylene (HDPE) treated with UV inhibitors.