Water Pooling Near Foundation

What you may be seeing

• Puddles along the slab or crawlspace wall
• Wet or dark soil against the house after rain
• Gaps or cracks between soil and slab
• Water marks on the slab edge or siding
• Mulch beds that stay flooded
• Moisture or musty smell inside near exterior walls

First question: does the ground slope away from the house?

Lay a level or straight board from the foundation outward. The soil should fall away from the house for the first several feet. If it's flat or falls toward the house, water will pool there.

If pooling is at downspouts

Roof water dumped at the foundation is the most common cause.

Possible causes:

• No downspout extensions
• Splash blocks displaced
• Buried downspout line clogged

If pooling runs along beds

Bed edging and built-up mulch can create a trough against the house.

Possible causes:

• Edging higher than the lawn
• Mulch or soil sloping toward the slab
• Beds lower than surrounding grade

If pooling is widespread around the house

The overall grade may slope toward the house, or the soil has settled around the slab.

Possible causes:

• Settled backfill
• Yard graded toward the house
• Neighbor runoff

Important: signs inside the house

Doors that stick, cracks in drywall or tile, or moisture on interior walls near the problem area can have several causes. If you see them with water pooling outside, get the drainage evaluated and consider a foundation professional.

Important: water entering the structure

If water gets into the garage, house or crawlspace, see water entering the house.

What you can check yourself

Only check these safely and after rain has stopped. Do not dig near marked utilities, and do not go near electrical equipment that is standing in water.

• Check where each downspout discharges
• Look at the slope away from the foundation with a level
• Look for beds or edging that trap water
• Check gutters for overflow during rain
• Look for gaps between soil and slab
• Photograph pooling during rain

Answer 20 quick questions → to get a preliminary drainage assessment.

What a drainage professional may evaluate

• Grade measurement around the foundation
• Downspout line flow testing
• Assessment of beds and hardscape trapping water
• Outlet route planning
• Recommendation to consult a foundation professional if movement signs exist

Most common causes

Downspouts too close

Roof water concentrated at the foundation.

Negative grade

Soil sloping toward the house.

Trapping beds and edging

Landscaping holding water against the slab.

Settled soil

Backfill settles over time next to the slab.

Overflowing gutters

Clogged or undersized gutters spill at the foundation.

Possible solutions

The right fix depends on where the water comes from, where it collects and where it can legally and physically go. These are the solutions most often considered:

Downspout drainage

Extensions or underground lines carrying roof water to a safe outlet.

Regrading away from the foundation

Add and shape soil so it falls away from the house.

Bed reshaping

Lower beds and remove edging that traps water.

French drain or surface drain

Collect water that still reaches the area.

Gutter repair

Clean, resize or repair gutters that overflow.

When to call a drainage professional

• Water regularly pools against the slab
• You see cracks, sticking doors or interior moisture
• Water enters the garage or house
• Regrading the area isn't straightforward

Bottom line

Water near the foundation should move away from the house. Downspout drainage and grading come first. Drains handle the rest.