The Problem: Protecting the Foundation from Water

Proper drainage is one of the most important factors in protecting a home’s foundation. When groundwater and roof runoff collect near the house, moisture can build up around the foundation and create ongoing maintenance concerns.

For this Castro Valley home, Ward Construction designed a drainage system to protect the front, right side and rear of the residence. The goal was to capture both underground water and roof runoff before it could accumulate alongside the home’s foundation.

The Solution: A Foundation Drainage System Around Three Sides of the Home

Ward Construction installed a new drainage system along approximately 13 feet of the front, the entire right side, and 19 feet along the rear of the residence.

The system was designed using two separate drain pipes installed within a rock-filled trench. A perforated drain pipe collects groundwater moving through the surrounding soil, while a second solid pipe carries water collected from the roof downspouts.

Using separate pipes for groundwater and roof runoff helps each system perform more efficiently while protecting the home’s foundation from multiple sources of water.

Connecting the Roof Drainage

An important part of the project involved improving the way roof runoff was handled.

Ward Construction connected the downspout at the front right corner of the home to the new solid drain pipe. Instead of allowing roof water to discharge near the foundation, the downspout now directs water into the drainage system, where it is carried to the sump basin for removal.

Installing a Sump Pump and New Street Discharge

The collected groundwater and roof runoff were directed into a sump basin, where a pump moves the water safely away from the property.

To create a proper discharge point, Ward Construction cut through the existing sidewalk, installed a drain pipe beneath the sidewalk and curb, and routed the water into the street gutter. After the installation, the disturbed concrete was repaired to restore the surrounding hardscape.

Built for Reliable Long-Term Performance

The drainage system was designed using installation methods intended to maximize long-term reliability.

The perforated drain pipe was installed below the grade beneath the home and pitched toward the sump basin at a minimum slope to promote consistent water flow. It was placed on a gravel bed with the perforations facing downward, then surrounded with clean drain rock inside a 12-inch-wide trench. A clean-out was also installed at the upper end of the perforated pipe, allowing the system to be inspected or cleaned if needed in the future.