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Service · 03

Rainfall does not damage property. Rainfall with nowhere to go does.

A two-inch rain over a typical North Texas lot is not a weather event. It is a volume problem with a destination problem attached. Sunday surveys where the water comes from, where it collects and where it is legally allowed to go — then builds the route.

01

Diagnosis

Read the water.

Almost nobody calls us about drainage. They call about a soft corner of the lawn, a patio that stays wet, mulch in the driveway, or a smell in the side yard. The first job is arithmetic: how much water lands on this property, and where does each part of it come from.

One inch of rain puts about 0.62 gallons of water on every square foot it touches. A 2,400 square foot roof therefore sheds roughly 1,500 gallons in a one-inch rain, and roughly 3,000 gallons in a two-inch rain — and it does not release that water evenly. It concentrates it at four or five downspouts. Add the driveway, the patio, the sidewalks and whatever arrives from uphill, and a modest lot can be handling several thousand gallons in under an hour.

That is why "it only floods when it rains hard" is a description of the problem, not an excuse for it. The system is not failing at the average rain. It is failing at the rain that matters. We size for the second one.

North Texas soil makes the arithmetic worse. Tight clay subsoil accepts water slowly, and once the top few inches are saturated, infiltration effectively stops. From that moment everything is surface flow, and surface flow obeys grade — not intentions.

Where the water is coming from

  • Roof area and downspoutsHighest volume, most concentrated
  • Driveway, patio, walksSheet flow, near zero absorption
  • Neighboring gradeWater arriving, not falling
  • Low points and swalesWhere volume becomes standing water
  • Compacted clayInfiltration stops early in a storm
  • Irrigation overrunKeeps a low spot saturated between rains
  • Pool decks and equipment padsBackwash and rinse volume

We measure elevations at the structure, the property line, the hardscape edges and every candidate outfall. The design follows the survey. It is the only order that works.

02

Anatomy

What a routed lot looks like underground.

Roof water gets captured, carried, collected at the low point, filtered through a gravel envelope and released downhill by gravity. Every element exists to keep water moving in one direction.

TOPSOIL CLAY SUBSOIL · LOW INFILTRATION ONCE SATURATED STRUCTURE DOWNSPOUT · ROOF VOLUME ARRIVES HERE 1 IN OF RAIN = 0.62 GAL PER SQ FT OF ROOF POSITIVE FALL · 2% MINIMUM AWAY FROM STRUCTURE BURIED COLLECTION LINE · RIGID SMOOTH-WALL FALL 1% MINIMUM · 1/8 IN PER FOOT CATCH BASIN AT THE LOW POINT PERFORATED PIPE · GRAVEL-WRAPPED DRAIN WASHED ANGULAR STONE IN NON-WOVEN GEOTEXTILE DAYLIGHT OUTFALL GRAVITY RELEASE · NO PUMP GRADE FALLS AWAY

Drainage cross-section · downspout to outfall

Collection, conveyance, interception and release. Component depths and fall are set by the elevation survey; the sequence does not change.

03

Scope

Systems we build.

Most properties need two or three of these, not all of them. The design decides which — and says plainly which ones you do not need.

  • Surface grading and positive fallFirst move, cheapest move
  • Downspout tie-insRoof volume buried and carried
  • Catch basins and inletsAt low points and swale ends
  • French drainsPerforated pipe, gravel, fabric
  • Channel and trench drainsAt driveways, patios, garage aprons
  • Dry creek bedsVisible conveyance, armored
  • Sump systemsOnly where gravity fails
  • Subsurface drainage under turfFor fields and flat lawns
  • Outfalls and pop-up emittersLegal, visible release point
  • Turf and hardscape restorationPart of the scope, not extra
01

Grade before pipe

If two inches of dirt in the right place solves it, we say so and we do that instead.

02

One direction, no low spots in the line

A pipe with a belly in it is a silt trap. Fall is verified as the trench is cut, not after.

03

The outfall decides the design

We find the legal release point first. Everything upstream is drawn back from there.

04

Selected work

Same yard. Different routing.

Drag the slider. Nothing about the rainfall changed between these two photographs.

Backyard with standing water covering most of the lawn after rain The same backyard fully drained with healthy turf and a flush catch basin
Before After
Southlake, TX Drainage · Grading

Rear Yard Collection and Outfall

Problem
Water stood across the rear lawn for days after every rain, with moisture holding at the patio edge and along the base of the fence.
Assessment
The elevation survey showed almost no fall behind the house and four downspouts discharging within a few feet of the same low corner. The turf was reporting a routing failure.
Solution
Regraded for positive fall, tied every downspout into a buried rigid collection line, set catch basins at both low corners, and ran a gravel-wrapped French drain to a daylight outfall in the side yard.
Outcome
Surface water clears within hours instead of days, the patio edge stays dry, and the fence line is no longer sitting in saturated soil.
See more projects
Open drainage trench with perforated pipe bedded in washed gravel and geotextile fabric Fabric, gravel envelope, pipe, verified fall

Construction

A pipe in dirt is not a drain.

The difference between a drain that works for fifteen years and one that silts shut in two seasons is entirely in the trench, and none of it is visible once the sod goes back down. This is the part worth asking every contractor about.

01

Non-woven geotextile, lapped

Fabric separates clay from stone. Without it, fines migrate into the voids and the envelope stops conducting water.

02

Washed angular stone, not screenings

Angular stone locks together and holds open void space. Rounded pea gravel and fine screenings pack tight and choke.

03

Pipe class matched to duty

Perforated pipe inside the envelope where the job is collection; rigid smooth-wall for conveyance, so it flows clean and can be cleaned out.

04

Fall shot, not eyeballed

Continuous fall of at least one percent, checked along the run. A single flat section undoes everything upstream of it.

05

North Texas clay

The soil under your house changes size.

This is the part of drainage that has nothing to do with your lawn. It is why we treat water at a foundation as a structural question rather than a landscaping one.

Much of the DFW area sits on expansive clay. These soils take on water and swell, then give it up and shrink. The movement is vertical and it is not uniform across a lot, because one side of a house is shaded, one side gets the roof discharge, one side has a bed on a drip line and one side bakes.

A slab does not mind moisture. It minds differential moisture, and it especially minds the cycle: saturated for a week after every storm, then desiccated through a stretch of hundred-degree days. That repeated shrink and swell at the perimeter is what moves corners, opens brick joints and sticks doors.

So the fix is not more water and it is not less water. It is stable water. Route the storm volume away from the perimeter so the soil is never soaked, and keep the perimeter from going bone dry in August so it is never fully shrunk. Drainage does the first half. Irrigation, tuned properly, does the second.

  • Roof discharge carried well past the perimeter, not splashed beside it
  • Positive fall for the first several feet out from the wall, in every direction
  • No planting bed built up against the brick, holding water at the slab edge
  • No irrigation head throwing directly onto the foundation line
  • Deliberate summer moisture at the perimeter instead of accidental drought

Sunday is not a foundation repair company. We manage the water that acts on soil. If a property needs structural evaluation, we will tell you that and stay in our lane.

06

Questions

Drainage, answered directly.

They are usually the same problem. Grading decides where water goes on the surface; drainage carries what grading cannot move. If water stands in a broad shallow sheet, the grade is flat or reversed. If water moves but arrives somewhere it should not, the routing is wrong. We survey elevations before deciding which one you are paying to fix.

On a lot with positive fall and somewhere for water to go, surface water should be gone within hours of the rain stopping. Water that sits for a day or more is not a soil condition to wait out. It means the low point has no outlet.

No. A French drain intercepts water moving through soil and needs somewhere lower to release it. If the yard is flat, or the water is sheet flow off a patio, or the roof is dumping thousands of gallons into one corner, a French drain alone will underperform. It is one component, not a strategy.

Somewhere lower that legally accepts it: a street, an alley, a swale, a drainage easement, or a point on your own property where discharge does not concentrate onto a neighbor. Outfall availability is the single biggest constraint on a drainage design, and it is the first thing we look for. Where no gravity release exists, the answer becomes a sump system, which changes both the cost and the maintenance picture.

We will not publish a price for work we have not surveyed, because the same symptom can be a one-day tie-in or a full rear-yard rebuild. What drives the number is straightforward, and you should ask any contractor to break it out this way: linear footage of pipe, trench depth, whether a gravity outfall exists or a sump is required, the number of hardscape crossings that have to be cut and restored, basin and inlet count, and how much regrading and turf restoration follows the excavation. You get a line-item scope with quantities before anything is dug.

Sometimes. If water on one side of a slab has to reach an outfall on the other, the options are a saw-cut crossing, a channel drain at the edge, or boring underneath. We price the crossing and the restoration as their own line items so you can see exactly what that decision costs and choose knowingly.

Both, for different jobs. Rigid smooth-wall pipe carries collected water with less friction and can be cleaned out properly, so we use it for downspout collection lines and long runs. Perforated pipe belongs inside a gravel envelope where the job is to collect water from soil rather than transport it. The failure we see most often is thin corrugated pipe used as a mainline, then crushed by traffic or silted shut.

Basins and grates need clearing of leaf litter and silt, outfalls need to stay open, and pop-up emitters need to seat properly. That is most of it. Full Season maintenance members get drainage inspection and basin clearing included, which is mostly about finding a blocked outfall before the next heavy rain finds it for you.

Next step

Tell us where the water goes.

Describe what you see and when you see it — the corner that stays soft, the day the patio floods, the downspout that has been eroding the same spot for two years. A Sunday specialist will walk the property, shoot elevations and come back with a written scope.

  • AssessmentOn-site, no obligation
  • You receiveLine-item scope with quantities
  • Also usefulPhotos of the yard mid-rain

Water actively moving toward a structure gets triaged ahead of routine work. If that is your situation, call (817) 320-0028 rather than waiting on a form.

Request a drainage assessment

Tell us what you’re seeing. We’ll tell you what’s causing it.

No obligation. A Sunday specialist will contact you to discuss your property.

Prefer to talk it through? Call (817) 320-0028

Request received.

A Sunday specialist will reach out to schedule your assessment and walk the property with you. If it’s urgent, call (817) 320-0028.

Drainage

Water is going somewhere. Decide where.

Every storm that leaves your lot the wrong way takes soil, grade and eventually structure with it. Routing is the cheapest work we do.

  • Elevation survey before any pipe is specified
  • Legal outfall identified before the design is drawn
  • Fabric, stone and pipe class stated in the scope
  • Restoration priced as part of the job, not after it