DRAINAGE + SITE WATER

How Surface Water, Soil Moisture, and Groundwater Impact Your Home

What Homeowners Usually Think

“If the yard isn’t flooding, the drainage must be fine.”

What Actually Happens

In the Pacific Northwest, poor drainage rarely looks dramatic.
Instead, water quietly saturates soil around the foundation, loads the crawlspace with moisture, pushes vapor through basement walls, and slowly rots structural elements.
By the time symptoms appear inside the home, water has usually been draining the wrong way for years.

Managing site water is the foundation of a dry, healthy, durable home.

Why Drainage Problems Happen in the PNW

1. Heavy Rain + Saturated Soils

Our clay-rich soils drain slowly.
During the winter, the ground stays wet for months, allowing water to accumulate around foundations.

2. Roof Runoff Not Managed Correctly

Common problems include:

  • downspouts dumping water next to the house

  • missing splash blocks

  • downspouts that end in planting beds

  • disconnected or clogged drains

One downspout can dump thousands of gallons of water per month into the foundation zone.

3. Poor Grading or Settled Soil

Landscaping often slopes toward the home instead of away.
Even a subtle slope can move significant water.

4. Failed or Improper Perimeter Drains

Many drains:

  • are clogged

  • collapse over time

  • are too shallow

  • were never installed

  • drain into saturated soil instead of daylight

A failed footing drain often goes unnoticed for decades.

5. Hardscapes Channel Water Toward the Foundation

Patios, driveways, walkways, and additions often change drainage patterns unintentionally.

6. Rising Groundwater + Hydrostatic Pressure

High water tables push moisture through concrete walls and slabs, creating basement seepage even without visible flooding.

Symptoms of Site Water Problems

These signs often appear long after the issue has begun:

  • Musty smell indoors

  • Efflorescence (white mineral deposits) on concrete

  • Damp or moldy crawlspace

  • Standing water near the foundation

  • Rot at siding or sheathing

  • Water staining at the bottom of walls

  • High indoor humidity in winter

  • Cracked or heaving walkways

  • Settling or sinking soil near your home

  • Downspouts overflowing

Many homeowners don't realize these are drainage issues — not interior problems.

Best Practices for Site Water Management in the PNW

1. Correct the Grading

The ground should slope away from the home at least 6" over 10 feet.
This is the simplest and most effective solution.

2. Extend Downspouts Away From the Foundation

Downspouts should discharge:

  • 5–10 feet away from the home

  • into a solid drain line that daylights

  • or into a drywell designed for your soil type

No downspout should end in a planter bed, mulch area, or tight against the foundation.

3. Install or Revive Footing Drains

Footing drains must:

  • be at the correct depth

  • have continuous slope

  • include filter fabric

  • drain to daylight or a pump

  • be free of clogs and root intrusion

A functioning perimeter drain is essential for homes with basements or crawlspaces.

4. Manage Hardscape Drainage

We correct patios, walkways, and driveways that slope toward the home by adding:

  • trench drains

  • channel drains

  • surface grading

  • cutting relief paths

5. Protect the Foundation Wall

Depending on site conditions, we use:

  • dimple mat

  • liquid-applied waterproofing

  • drainage board

  • proper footing drain integration

This keeps hydrostatic pressure off the foundation.

6. Create Catch Basins and Swales (When Needed)

These redirect surface water safely across the site instead of letting it pond next to the house.

7. Under-Slab and Crawlspace Water Management

For severe conditions we may install:

  • sump pumps

  • internal perimeter drains

  • French drains inside the crawlspace

  • soil vapor barriers

  • dehumidification systems

How Emerald State Contracting Solves Drainage Problems

1. Diagnose the Entire Site — Not Just the Symptom

We walk the property and look at:

  • roof geometry

  • downspout paths

  • slope

  • soil type

  • hardscape layout

  • foundation lines

  • crawlspace/basement conditions

  • water table behavior

This gives us the full picture.

2. Identify Root Causes

We determine whether the problem is:

  • surface water

  • groundwater

  • hydrostatic pressure

  • failed drains

  • bad grading

  • poor design or site layout

3. Design a Comprehensive Water Management Plan

This may include a combination of:

  • grading correction

  • downspout reroutes

  • trench drains

  • sump systems

  • drain line replacements

  • foundation protection

4. Implement Durable, Long-Term Solutions

We install systems that perform for decades, not just one rainy season.

5. Repair Foundation Damage (If Present)

If water has compromised rim joists, sheathing, or crawlspace materials, we repair them with proper air, vapor, and water control.

Why This Matters

Site water management protects:

  • your foundation

  • your crawlspace or basement

  • your insulation and framing

  • your siding and sheathing

  • your indoor air quality

  • your home’s structural lifespan

A dry home starts with a dry site.

When to Call a Professional

You should have your drainage evaluated if:

  • You smell musty odors indoors

  • Your crawlspace or basement is damp

  • You see water near your foundation after rain

  • You experience interior moisture problems

  • Your downspouts are not draining properly

  • You have soggy soil or standing water

  • You own a home in a low-lying area

  • The home was built before 1990