Dry wells, rock pits, and infiltration features

Normal function

It temporarily stores runoff and disperses it into the soil when the soil, groundwater, setbacks, and overflow path make infiltration appropriate.

What a homeowner may notice

• Slow drainage, surface ponding above the pit, settlement, overflow during storms, clogged inlet, or water backing toward the foundation.
• Rock/soil fines filling the chamber, collapsed structure, or no overflow/maintenance access.
• Installation in dense clay, high groundwater, contaminated soil, or too close to a foundation without design review.
• Dry well receiving more roof area than its storage/infiltration capacity.

Professional inspection

Confirm soil infiltration, high-water conditions, setbacks, roof area, inlet filtration, cleanout, overflow, and outfall. Test the inlet and inspect the chamber where possible; do not assume an old rock pit is functioning.

Repair or replacement path

Clean inlet and chamber, replace collapsed parts, add pretreatment and overflow, or redesign the system. Use a solid conveyance from downspouts and keep the feature away from the foundation per site design.

Typical materials and equipment

Dry well chamber or stone, geotextile, solid pipe, inlet filter/catch basin, cleanout, overflow/emitter, gravel, and restoration.

When to act

Investigate slow or overflowing wells before redirecting more roof water into them.

What moves the price

Soil, groundwater, volume, depth, excavation access, roots/rock, pretreatment, overflow, local requirements, and restoration.