How to Install a Dry Well to Solve Ponding Problems

Ponding water in your yard or around your home can lead to numerous issues, from soggy lawns and unpleasant odors to structural damage and foundation problems. One effective and environmentally friendly solution to manage excess surface water is installing a dry well. A dry well is an underground structure that collects and disperses stormwater runoff, allowing it to slowly seep into the surrounding soil, thereby alleviating ponding and flooding issues.

In this comprehensive guide, we will walk you through everything you need to know about installing a dry well, from understanding what it is, assessing if your property is suitable, planning and preparing for installation, to the step-by-step process of putting one in place.

What Is a Dry Well?

A dry well is essentially a large, underground pit filled with stone, gravel, or a prefabricated plastic chamber that temporarily stores stormwater runoff. The water collected drains through the porous walls of the structure and permeates into the surrounding soil over time.

Unlike traditional drainage systems that move water away from your property via pipes or gutters into municipal storm sewers (or sometimes directly into streams), dry wells provide localized infiltration. This method reduces runoff volume, mitigates erosion, helps recharge groundwater aquifers, and controls nuisance ponding, all while being a sustainable way to manage stormwater.

Why Install a Dry Well?

Common reasons homeowners and landscapers install dry wells include:

Prevent ponding: Standing water after rains can kill grass, damage plants, and attract mosquitoes.
Protect foundations: Constant moisture around a building’s foundation can cause cracks and structural damage.
Improve drainage: Slow infiltration reduces runoff problems on slopes or low areas.
Comply with regulations: Some local codes require on-site stormwater management.
Reduce erosion: Properly managed runoff prevents soil washing away.
Environmentally friendly: Infiltration methods reduce pollutants reaching natural waterways.

If you have areas in your yard that accumulate water after rainfall or notice soggy spots that never seem to dry out, installing a dry well could be an effective fix.

Assessing Your Site for Dry Well Installation

Before beginning any installation project, it’s critical to determine if your property is suitable for a dry well system.

Soil Permeability

The ability of soil to absorb water determines how well a dry well will function. Conduct a simple percolation test:

Dig a hole about 12 inches wide and 12 inches deep where you plan to install the dry well.
Fill it with water and let it drain completely.
Refill the hole with water and measure how long it takes for the water to drain.

Ideally, water should drain within 30 minutes to 4 hours. Soil that drains too quickly (like sandy soil) might not hold enough water around the dry well for saturation benefits, whereas very slow-draining soils (like clay) can cause overflow issues.

Location Considerations

Distance from structures: The dry well should be at least 10 feet away from building foundations, septic systems, or wells to prevent water-related damage or contamination.
Downhill placement: Position the dry well in a low spot or where runoff naturally collects.
Utility avoidance: Check for underground utilities before digging.
Accessibility: Make sure the area is accessible for excavation equipment or manual digging tools.

Local Regulations

Check with your local municipality or county regulations regarding stormwater management. Some areas require permits for installing drainage structures such as dry wells.

Materials Needed for Installing a Dry Well

Gathering all necessary materials beforehand makes the project more efficient.

Common Materials

Dry well chamber: Prefabricated plastic or concrete chambers designed specifically for infiltration.
Gravel/stone: Clean crushed stone (typically 3/4 inch) to surround and backfill the chamber; also used as filler inside some chambers.
Geotextile fabric: Permeable landscape fabric to prevent soil from clogging the gravel bed.
PVC pipe: To direct runoff from gutters or drainage pipes into the dry well.
Pipe fittings/adapters: Elbows, connectors as needed.
Shovel/excavation tools
Level
Measuring tape

Optional Tools & Equipment

Excavator or mini-digger (for large installations)
Wheelbarrow
Tamper (to compact soil)
Safety gloves and goggles

Step-by-Step Guide: How to Install a Dry Well

1. Plan Your Installation

Identify the area where water collects most frequently. Decide on the size of your dry well based on:

Amount of runoff expected (roof area draining into it)
Soil absorption rate
Available space

A general guideline: one cubic foot of dry well can infiltrate approximately 0.5 cubic feet of runoff. For example, if you want to handle runoff from a 500 square foot roof during a one-inch rain event:

Runoff volume = Roof area x Rainfall depth
= 500 sq ft x (1/12) ft = ~41.7 cubic feet
Dry well volume needed  41.7 x 2 = about 83 cubic feet

(The factor of two accounts for safety margin.)

2. Mark and Excavate the Hole

Mark the location clearly using spray paint or stakes.

Excavate a hole larger than the dimensions of your dry well chamber, usually about 6 inches wider on all sides, to allow room for gravel backfill.

The depth should accommodate:

The height of the chamber
Gravel base layer (typically 6-12 inches)
Gravel surround on sides
Space above for topsoil restoration (if applicable)

Make sure the bottom of the hole is level by checking with a carpenter’s level.

3. Prepare Base with Gravel

Add a 6-12 inch layer of clean crushed stone at the bottom of the excavation.

This layer assists infiltration and supports the chamber evenly.

Level and compact this gravel base before proceeding.

4. Wrap Hole Walls with Geotextile Fabric

Lay permeable geotextile fabric along the sides and bottom of the hole before placing gravel or chambers.

This prevents soil intrusion into your gravel bed which could clog infiltration pathways over time.

Leave excess fabric so you can fold it back over the top layer later.

5. Install Dry Well Chamber

Place the prefabricated plastic or concrete chamber on top of the gravel base.

Ensure it sits level, stable, and aligned with any inlet pipe you plan to install.

If needed, assemble multiple chambers side by side for larger capacity according to manufacturer instructions.

6. Connect Inlet Pipe

Cut appropriately sized PVC pipe(s) from downspouts or drainage lines leading runoff into the dry well location.

Insert pipe ends securely into inlet holes of the chamber using fittings if required; apply waterproof sealant if necessary.

Make sure pipes slope downward toward the chamber at about 1-2% grade for good flow.

7. Backfill Surrounding Gravel

Fill around all sides of the chamber with clean crushed stone up to about an inch below ground level.

Avoid soil backfill here as it will diminish infiltration capacity.

Compact lightly but do not crush stone particles too much, it’s important they remain porous.

8. Fold Geotextile Fabric Over Gravel Layer

Fold excess geotextile fabric over top of gravel backfill to cover completely before adding soil on top.

This further protects against soil mixing into gravel during restoration work above ground.

9. Restore Surface Soil and Landscaping

Backfill remaining inch or two with native topsoil and restore grass seed or other surface landscaping materials as desired.

Water thoroughly to encourage grass growth and settle soil evenly without disturbing gravel below.

Maintenance Tips for Dry Wells

While typically low maintenance compared to other drainage options, some care will extend your dry well’s lifespan:

Keep gutters clear so debris does not clog inlet pipes.
Inspect annually after heavy rains for signs of overflow or blockages.
Remove sediment buildup in inlet pipes when necessary.
Avoid driving heavy equipment over installation areas which may compact soils.

If ponding recurs near your dry well during storms after several years, consider having a professional inspect possible clogging or soil compaction issues.

Alternative Solutions & Enhancements

If space allows or if additional capacity is needed:

Use multiple interconnected dry wells.
Combine with rain gardens to absorb excess runoff.
Direct overflow lines safely away from structures if heavy storms exceed capacity.

For highly impermeable soils where infiltration isn’t feasible, other drainage improvements like French drains or surface grading may be better suited instead of dry wells alone.

Conclusion

Installing a dry well is an effective solution for managing ponding problems by capturing stormwater runoff underground and encouraging natural infiltration into surrounding soils. It can protect your landscape health, safeguard your home foundation, reduce mosquito breeding grounds, and promote sustainable water management practices on your property.

By carefully planning based on site conditions, especially soil permeability, and following proper installation steps including excavation, gravel base preparation, use of geotextile fabric, chamber placement, piping connection, and backfilling techniques, you can create a functional system that minimizes standing water issues efficiently for years to come.

Keep in mind local codes may require permits or inspections before installation; consulting professionals when in doubt ensures safe compliance while addressing drainage challenges effectively. With patience and attention to detail, installing your own dry well can be an achievable DIY project that improves both property value and outdoor enjoyment by solving persistent ponding problems once and for all.