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Building a Dry Well for Downspout Drainage

For a clean, lasting downspout outlet: dig a 24-inch cube, line with filter fabric, fill with coarse gravel to 6 inches from top, cover with fabric, then top with 2–3 inches of decorative river rock. This dry well captures runoff, slows release, and prevents erosion. Pipe the downspout directly into the gravel core.

Size the well to your roof area—larger roofs need bigger/deeper pits. Keep it 5+ feet from foundations, especially with basements. Fabric prevents soil migration into gravel. This BMP (Best Management Practice) recharges groundwater and handles heavy rain beautifully.

Landscaping and Design: Solving Hillside Erosion from Sprinkler Drainage: Expert Advice; Garage Flooding: French Drain with Polyethylene Pipe and Gravel; Fixing Drainage Behind a Retaining Wall; Hillside Erosion Control: Drain Pipe Extension and Slope Stabilization; Designing a Drainage Trench System for a Flat 2-Acre Yard; Juniper Die-Off on a Slope: Likely Water Pooling at the Base; Evaluating a Contractor's Drainage Installation: Holes Up or Down?; Fixing Driveway Edge Erosion with Rip Rap and Plantings; Drainage Behind a Low Hillside Planter Wall: Gravel, Pipe, and Footing Details; Pre-Emergent Herbicide After Heavy Rain: Still Effective?

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