Redirect Groundwater Before It Reaches Your Basement

Interior and Exterior French Drain Systems for Wet Basements and Yards

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Groundwater doesn't need a crack or hole to cause problems—it can seep through foundation walls, rise through basement floors, or saturate your yard until the soil can't hold anymore. You might see damp spots on basement walls, standing water in low areas of your yard, or a persistent musty smell that won't go away. Allied Water Services installs French drain systems that capture and redirect groundwater before it reaches your basement or floods your property.

A French drain is a gravel-filled trench with perforated pipe that collects water and carries it to a discharge point, either at the surface or underground. Exterior systems intercept groundwater before it reaches the foundation. Interior systems capture water that's already entering the basement and route it to a sump pump or floor drain. Both are built with proper gravel, filter fabric, and piping designed for local soil and water conditions.

If your basement stays damp or your yard is too wet to use after rain, a French drain may be the long-term water control solution you need.

Key Benefits of This Service

Installation begins with trenching along the area where water collects or enters. You'll see us dig down to the footing for interior drains or along the foundation perimeter for exterior systems. The trench is lined with filter fabric, filled with clean gravel, and fitted with perforated pipe that slopes toward the discharge point.

Once the system is installed, groundwater flows into the pipe instead of pooling in your basement or yard. Allied Water Services designs each system to handle the specific water load your property experiences, whether that's seasonal groundwater or year-round saturation. The system works passively—no pumps or power required unless discharge needs assistance.

Interior French drains are commonly paired with sump pumps to lift water out of the basement. Exterior drains discharge to daylight, storm systems, or dry wells depending on lot slope and local codes. French drains are one of the most reliable solutions for wet basements and chronically soggy yards, especially in areas with high water tables or clay soil that doesn't drain well naturally.

Property owners often need to understand the difference between interior and exterior systems and what each one accomplishes. These questions address the most practical considerations before scheduling installation.

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What to Expect When You Book

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● What to Expect When You Book ●

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What's the difference between interior and exterior French drains?

Exterior drains intercept groundwater before it reaches the foundation. Interior drains capture water that's already entering the basement and route it to a sump or drain.
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How deep does a French drain need to be?
Exterior drains typically run along the foundation footing, usually four to six feet deep. Interior drains are installed just below the basement floor slab.
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Will a French drain stop all basement moisture?
It controls groundwater infiltration, which is a major cause of wet basements. It won't stop condensation or leaks from plumbing, but it addresses the water coming from the soil.
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Where does the water discharge?
Exterior systems discharge downhill to daylight, into a storm line, or to a dry well. Interior systems drain to a sump pump that pumps water outside or into a drain system.
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How long does a French drain last?
When installed with quality materials and proper fabric, French drains function reliably for decades. Clogging is rare if the system is built correctly from the start.

If groundwater is flooding your basement or keeping your yard too wet to use, a French drain system offers long-term control without ongoing maintenance. Contact us to evaluate your property and discuss the best drainage approach for your situation.