Basement Waterproofing in Covington, WA

Basement waterproofing in Covington: what to know

On Alderwood soils, one of the types the city’s code names, a dense, extremely firm layer sits roughly 20 to 40 inches down, and the soil survey records a perched water table above it at times from December through April. Water that cannot sink through that layer travels sideways and settles against a wall or under a floor, which is how a house ends up damp in February and dry in August.

Not every lot fits that pattern. Everett soils, also named in the code, are gravelly outwash that drains freely, so there the likelier causes are roof water, grading, and a clogged footing drain. A lot beside Soos or Jenkins creek or a wetland can carry its own groundwater.

Permits and rules in Covington

The city side of this work is the dig and the outlet. The grading code’s small-excavation exemption stops at three feet of vertical depth, and a trench down a basement wall goes deeper, so we ask Community Development whether a clearing and grading permit applies. Connections to the city’s stormwater system are regulated, with requests going to the Public Works Director. We confirm both points for your address before we quote.

Rules change and vary by parcel, so we confirm the current requirements with the city before we start.

How we approach it

Name the foundation type, then trace gutters and grading before opening ground
Read the problem between December and April, when perched water shows
Test the soil down to the dense layer to see where winter water travels
Plan the footing drain outlet to a legal point on your lot

For the full process, see our Basement Waterproofing page.

Our basement waterproofing work, serving Covington

Examples of our work. We build basement waterproofing in Covington and the cities around it. See all of our work

Questions from Covington homeowners

Why is my Covington basement wet in February but dry in August?

A seasonal pattern points to groundwater, not a leak. The soil survey records a perched water table in Alderwood soil at times from December through April, and that water can push on a wall or floor. Summer dries it out. We check the outside first.

Does Covington require a permit to dig down my foundation wall?

Possibly. The grading code exempts only excavation less than three feet deep and 50 cubic yards, and a trench beside a full basement wall is usually deeper. Critical areas can add review. We ask Community Development how it treats repair digs before opening the ground.

Can I tie my footing drain into the street storm drain in Covington?

Not on your own. The code regulates connections to and changes of the city’s stormwater system and prohibits illicit connections, and sanitary sewer lines are off limits. We look for a legal outlet on your lot, such as the storm stub where one exists.