I talked to two landscapers about what’s involved and received inspiration from a homeowner who installed her own.

“It was easy,” Hillsborough resident Heather Walker said. “It was a weekend project.”

She didn’t research French drains, but she did watch landscapers install a drain and retaining wall in another area of her yard. So when her family had a sidewalk installed behind their screened-in porch and patio because of a constant soppy ground, Walker decided she could install a French drain next to it.

The idea was to keep water from washing from her sloped back yard onto the sidewalk and to do away with a damp area where nothing seemed to grow well.

“It’s so not scientific,” she said of the work she did on her drain. “It’s kind of by slope. I made sure it would slope downward. I had to dig certain areas deeper, so it would maintain a slope.”

What she ended up with is a 40-foot drain that runs alongside the sidewalk and behind a patio, draining out on the side of her yard. But the drain isn’t noticeable and instead looks like part of the landscaping.

That downward slope is important, Chapel Hill landscapers Johnny Johnson and James Riley agree. Johnson, who owns Johnson Landscaping and Garbage Service, readily says homeowners can take on French drain projects. Riley, who owns New Growth Landscapes, advises more caution, suggesting that homeowners seek professional advice.

“Drainage can create problems for the foundation of the house,” Riley said. “So drainage is a tricky situation. It’s not something to take lightly, especially with our clay soils. Clay is really hard to drain.”

But he acknowledges small projects are doable by homeowners — as long as they get the water to actually drain.

WHAT’S A FRENCH DRAIN?

A French drain is the opposite of a septic system, which disperses used water throughout the soil. A French drain is a pipe with holes in it that removes moisture from the soil to dry out wet areas. The drain must be installed so that water flows freely downhill once it reaches the pipe.

“That’s usually where the mistakes happen,” Riley said. “People just put it in a flat area and expect it to drain. If the water doesn’t move, then it’s just going to be sitting there in that pipe.”

REASONS TO INSTALL A FRENCH DRAIN

• If you have a yard that stays soft or wet year-round. • If you want to divert water from a wall or from your house. • If you have a natural spring in your yard.

TOOLS FOR THE JOB

• Trenching shovel or machine to dig the trench for the pipe. Such machines, with the brand name Ditch Witch, can be rented from businesses like The Home Depot.

“I’ve seen people dig them by hand, but that’s a lot of work,” Johnson said.

He also noted, “It doesn’t have to be a trenching shovel, but it works a whole lot easier with a trenching shovel because most normal shovels are too wide.”

• 4-inch corrugated, perforated drainpipe with filter sock. Pipes and socks can be bought separately, and pipes without the sock —or sleeve — may be used. However, both landscapers recommended using the combination of pipe and cloth to keep sediment from clogging the pipe.

• Gravel to surround the pipe and allow water to percolate into the pipe. • Wheelbarrow to hold and transport dirt from the trench as well as gravel to surround the pipe. • Shovel to move dirt and gravel. • Rake to spread dirt and gravel.

WHAT TO DO

Specifics and costs will vary depending on the reason for the drain, but here are some basics on installing one:

• Assess your needs, determining where the water is coming from, where you want it to go and what you need. French drains extract and move subsurface water. Surface drains move water collecting on the surface of the ground. Large areas that need to be drained may require a drainfield, a series of French drains. Riley said these are usually placed in a herringbone design, with a mainline and small lateral lines draining into the mainline. “Otherwise in our soil, since it’s clay, you’re only going to drain four feet,” he said. • Determine whether you need professional help. Riley suggests landscapers can be contracted for small drainage projects. Drainage problems of a larger scale and scope may require a drainage engineer. He recommends Horvath Associates in Durham. • Dig your trench, leaving room for gravel below and above the pipe and being sure to create a downward pitch. The depth of the trench could be 8 to 12 inches in places depending on how much distance the pipe needs to cover, Riley said. Johnson noted that ideally 6 to 8 inches of rock should cover the top of your pipe, but that a shallower amount may be needed depending on the grade of the land. The key is making sure the trench has a downhill pitch. If your drain is only handling subsurface water, you can cover the gravel with soil and seed it with grass or plant shrubbery or other plantings around it. If you are trying to move some surface water as well, leave just gravel on top of the pipe. Johnson recently installed a drain at Chapel Hill resident Tom Grizzle’s home. There he covered the pipe with gravel and made a walkway out of the drainage area, placing flagstones on top. • Ensure there’s a place for the water to go. Riley noted that if there is no place for the water to flow downhill, then a collection well or drywell pit can be created. That basically requires digging a large hole and filling it with gravel so water can collect there and slowly wick out into the soil. If a collection well isn’t feasible, water can be piped to a collection tank and mechanically pumped to another area.

“It’s no good if you don’t have a tail end to dump the water out in,” Johnson said.

HEATHER WALKER’S PROJECT

Walker estimates she spent less than $200 for materials and rock, not counting landscape plantings and mulch.

She used pea gravel underneath her pipe, which does not have a cloth cover, and covered the top of the pipe with river stone — a 2- to 4-inch stone called “Winding River” from Scott Stone in Mebane. Walker bought the stone in 5-gallon buckets.

The trench she dug with a garden spade was about six inches wide, and she planted liriope beside the stone-covered pipe to help prevent grass from growing between the rocks. She said she likes the flat blade of the spade because it made it easy to cut edges and dig the trench.

The first 30 feet of her pipe is corrugated, perforated drainpipe, bought in 10-foot sections. Walker estimates she used about four to five buckets of stone to cover that portion. The last 10 feet is a solid drainpipe that runs underneath a flowerbed.

“I was just winging it,” Walker said, “but it seems to be working.”

Got a remodeling story to share? Or would you like to see a particular aspect of remodeling featured? Contact Catherine Wright at catherine.wright@gmail.com.