Find where the water comes from, then move it

Almost every water problem on a property here is one of three things, and they need completely different fixes. Surface water running downhill across the yard wants intercepting before it arrives — a swale or a curtain drain uphill of the house. Groundwater moving through the soil at shallow depth wants a footing or curtain drain at the right depth. And roof water is usually the largest single volume on the site and the cheapest to redirect: a 2,000 sq ft roof sheds well over a thousand gallons in an inch of rain, and if the downspouts discharge two feet from the foundation, that is where it goes.

Which is why the diagnosis matters more than the product. A French drain installed for a groundwater problem that is actually a downspout problem is a trench full of stone that changes nothing. We walk the site during or straight after a rain where we can, because a dry site tells you far less than a wet one.

The soils east of the Hudson make this harder than it sounds. Much of this area sits on dense glacial till — Woodbridge, Ridgebury and their relatives — with a compacted layer a foot or two down that water will not pass through. That is why a dry well works on one property and fills up permanently on the next one down the road, and it is worth a test pit before committing to an infiltration solution.