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Quick, low-risk steps

  1. Stay out of water near electrical outlets, appliances, or cords.
  2. If water may contain sewage, avoid contact and call a plumber or restoration service.
  3. From a dry area, note where water is entering and how high it gets.
  4. Record the timing of rain and when water appeared.
  5. Check gutters and downspouts from outside only if safe.
  6. Call a waterproofing pro to assess the source and recommend a plan.

Safety First: When to Stay Out

Water in a basement can hide serious dangers. If water is touching or near electrical outlets, appliances, or extension cords, do not step into it. Even a small amount of water can conduct electricity and cause shock. If you cannot reach the breaker box without entering water, call your utility company to cut power from outside.

Sewage backups are another emergency. If the water smells foul or you suspect a sewer line has backed up, avoid all contact. This water contains harmful bacteria and viruses. Call a plumber or a water damage restoration company that handles contaminated water. Do not use household fans or vacuums on sewage water.

  • Do not enter water near electrical sources.
  • Call the utility company if you can't safely cut power.
  • Treat foul-smelling water as a sewage risk.
  • Contact a plumber or restoration pro for sewage cleanup.

Observe the Water Entry Points

Once you're sure the area is safe, look for where water is coming in. Common entry points include floor-wall joints, cracks in walls or floors, and around pipes. Water may also seep up through the floor if the water table rises. Use a flashlight to inspect corners and behind stored items.

Take clear photos and videos of the water entry. Mark the high-water line on the wall with tape or a pencil. This evidence helps a waterproofing professional understand the severity and pattern. Note whether water enters during heavy rain, light rain, or hours after rain stops—this timing hints at the source.

  • Check floor-wall joints, cracks, and pipe penetrations.
  • Look for seepage through the floor.
  • Photograph entry points and mark water lines.
  • Record timing: during rain, after rain, or both.

Check Outside from a Safe Distance

From outside, look at your gutters and downspouts. Are they clear of debris? Do downspouts extend at least several feet away from the foundation? Clogged gutters can overflow and dump water right next to the basement wall. Also check the ground slope—soil should slope away from the house, not toward it.

Do not dig or excavate near the foundation. Underground utilities like gas, electric, and water lines may be buried there. Before any digging, you must call 811 to have utilities marked. This is a free service, but it takes a few days. Never assume you know where lines are.

  • Clear gutters and extend downspouts away from the house.
  • Check that soil slopes away from the foundation.
  • Do not dig without calling 811 first.
  • Look for pooling water near the foundation after rain.

Questions to Ask a Waterproofing Pro

When you call a waterproofing contractor, they should inspect both inside and outside before giving a quote. Ask them to explain exactly where they think the water is coming from and why. A reliable pro will point to specific evidence, not just guess. They should also discuss drainage, discharge, and any needed permits.

Get at least three written quotes that detail the scope of work. Compare what each includes: interior or exterior methods, linear feet of drain tile, sump pump and backup, demolition and restoration, and warranty terms. Avoid any contractor who pressures you to sign immediately or won't provide a detailed written estimate.

  • Ask the pro to state the proposed water source and evidence.
  • Request a detailed scope: drainage, pump, discharge, restoration.
  • Get at least three written quotes to compare.
  • Ask about permits, electrical work, and warranty coverage.

Take this with you

Evidence and scope checklist

  • Proposed water source and evidence
  • Interior or exterior waterproofing method
  • Linear feet of drain tile or membrane
  • Sump pump type and backup system
  • Discharge route and distance from foundation
  • Demolition and material handling plan
  • Permit and electrical work responsibility
  • Finish restoration included or excluded
  • Warranty length and what it covers
  • Maintenance requirements after installation
Open the interactive private worksheet →

Common questions

What homeowners ask next

Can I pump out the water myself?

Only if it's a small amount of clean water and you can do so safely. Pumping too fast can cause walls to collapse from pressure imbalance. For large or contaminated water, call a professional.

Will my homeowner's insurance cover this?

Check your policy. Most standard policies do not cover groundwater seepage or flood damage. Sewer backup coverage is often an add-on. Contact your insurer to confirm what is covered.

How soon should I call a waterproofing company?

After ensuring safety and documenting the issue, call as soon as practical. Standing water can lead to mold and structural damage. A professional can assess the urgency and recommend next steps.

Evidence

Sources used for this guide

Research checked July 31, 2026

Optional next step

Need an on-site professional?

Use the guide and worksheet first so you can describe the situation and compare the full scope. A referral is optional; you can also contact a licensed local provider directly.

Referral matching is not enabled yet.

We have not enabled a provider route for this site. Use the checklist to contact and verify local providers yourself; urgent hazards should go to the appropriate emergency or public service.