Why so many Westerville-area basements leak
If you live north of Columbus and your basement takes on water, the main cause is the ground under your house. Delaware County and northern Franklin County sit on glacial till, the dense mix of clay, silt, sand and stones that the last Wisconsinan glacier left behind when it retreated about 15,000 years ago, according to the Delaware County soil survey. Till drains slowly. When rain or snowmelt soaks in, the water can't sink quickly through the clay, so it moves sideways along the denser layers until something stops it. Very often that something is your basement wall.
Soil surveys back this up. Summaries of USDA soil data put about 71% of Franklin County's mapped land, and about 84% of Delaware County's, in soils whose seasonal high water table limits basements. Common local soil series such as Crosby, Bennington and Kokomo are classified as somewhat poorly to very poorly drained. Your lot may be better or worse than average, but if you've had water in the basement here, you're far from alone.
The usual signs, and what they tend to mean
Water where the wall meets the floor
This is the classic sign of hydrostatic pressure. Water collects in the soil against the footing and pushes in through the "cove joint," the seam between the poured floor and the wall. It's usually fixed with an interior drain system and sump pump.
Damp streaks below a crack
Poured concrete walls often develop vertical shrinkage cracks. Many are cosmetic, but once one leaks, it can usually be sealed from inside with a polyurethane or epoxy injection.
A sump pump that never stops (or a pit with no pump)
If the pump runs long after the rain stops, the water table around the house is high. That's exactly when a failed pump or a power outage floods the basement. A backup pump or a battery backup is worth discussing.
Water only in heavy storms, near one corner
This is frequently a surface-water problem. Look for a downspout emptying next to the house, a clogged window well, or soil that has settled and now slopes toward the foundation. These are sometimes the cheapest fixes.
White, chalky residue on block walls
That's efflorescence: minerals left behind as water passes through the masonry. It shows moisture is moving through the wall even if you never see standing water.
Bowing, stair-step cracks or horizontal cracks
Horizontal cracks in block walls, or a wall leaning inward, can mean soil pressure is moving the wall. This is a structural issue, not just a leak, so get it evaluated soon.
What waterproofing typically costs
Prices vary a lot with the size of the basement, how much of the perimeter needs work, and whether the space is finished. As a national reference point, HomeGuide's 2026 guide puts interior waterproofing at roughly $6,000 to $12,000 and exterior waterproofing at roughly $10,000 to $18,000. Smaller jobs, like sealing a single crack, adding a sump pump, or extending downspouts and regrading, can cost much less. A reputable contractor will look at the basement and give you a written quote that spells out exactly which walls, how many linear feet, and what warranty you get.
How to compare quotes
- Ask what's causing the water, not just what they'll install. A good inspection explains whether the problem is surface water, hydrostatic pressure, a crack, or a structural issue.
- Get the scope in writing: linear feet of drain, pump model, discharge location, crack locations, and who repairs drywall or carpet afterward.
- Read the warranty. Is it transferable to the next owner? Does it cover only the drain system, or "no water" in the treated area?
- Confirm insurance and that the contractor pulls any permits your city requires.
- Know your cancellation rights. Under Ohio's Home Solicitation Sales Act, many contracts signed in your home give you three business days to cancel. The contractor should give you the cancellation notice in writing.
- Be wary of high-pressure tactics: "today-only" discounts, or claims that the house will collapse if you don't sign tonight.
Where we connect homeowners
We focus on Westerville, Lewis Center and the Orange Township/Polaris area, Worthington, New Albany, Gahanna, Galena and Sunbury, plus north Columbus neighborhoods. Pick your area below for local notes, or go straight to a service page.
How this service works
This website is a referral service, not a waterproofing company. When you send the quote form, your request goes to one independent local contractor who serves your area. You aren't sent to a call center, and your information isn't sold to a list. The contractor schedules the inspection, sets the price and does the work, and you're free to get other quotes. Contractors pay us for referrals, which is how the site stays free for homeowners. Read more about how referrals work.
Sources
- Soil Survey of Delaware County, Ohio (USDA-NRCS), glacial geology section: auditor.co.delaware.oh.us
- Franklin and Delaware County soil summaries based on USDA soil data: foundationsoils.com (Franklin), foundationsoils.com (Delaware)
- Franklin Soil & Water Conservation District, "Restrictions on soil": jacksontwpfranklinoh.gov
- HomeGuide, basement waterproofing cost (2026): homeguide.com