Is it cheaper to bury all the downspouts at once?
Usually. Downspouts on the same side of the house can share one trench and one outlet, so the digging, the outlet and the restoration are paid for once instead of for each downspout.
Cost guide
How much does underground downspout drainage cost in Irving?
Burying downspouts is usually the cheapest drainage fix with the biggest effect on a slab. The run length and the outlet decide where a job lands.
Updated November 5, 2026
Key takeaways
- As a national budgeting range, a buried downspout runs about $150 to $350 per downspout.
- Several downspouts sharing one trench cost less per downspout than separate runs.
- University Park requires roof drainage to be piped to the curb or alley, which lengthens runs and adds cost.
- Pipe size follows roof area: about 620 gallons fall on 1,000 square feet of roof per inch of rain.
As a national budgeting range, an underground downspout runs about $150 to $350 per downspout. A short line to a pop-up emitter in an open lawn is the low end. Long runs to the curb, a curb core, crossing a walk, or a city rule like University Park’s push the cost up. Rein Irving Drainage Company explains each factor below.
Why roof water is worth the money
Each inch of rain on 1,000 square feet of roof sheds about 620 gallons, and gutters deliver it to a handful of points. NOAA’s Atlas 14 puts Irving’s 2-year storm at 1.77 inches in one hour, so a 1,000 square foot roof section can send roughly 1,100 gallons to one downspout in an hour of an ordinary heavy storm. Dumped at the slab on expansive clay, that is the most common source of wet ground at a foundation. The roof runoff guide works through the math for larger roofs.
Burying downspouts in smooth solid pipe carries that water to an outlet instead. It is often the first fix to make because it can shrink or remove the need for a French drain or regrading.
What sets the price per downspout
| Factor | Toward $150 | Toward $350 or beyond |
|---|---|---|
| Run length | 10 to 20 ft to a lower part of the lawn | Long run to the curb or alley |
| Outlet | Pop-up emitter | Curb core, swale tie-in or pump |
| Pipe | Standard size for a small roof section | Larger pipe for a big roof section or merged lines |
| Shared trench | Several downspouts on one line | Each downspout on its own run |
| Crossings | Open lawn | Walks, driveway, beds and tree roots |
| Restoration | Narrow strip of sod | Sprinkler lines, beds, concrete patch |
| City rule | No routing requirement | Curb or alley required (University Park) |
Pipe type matters as much as size. Roof water belongs in solid pipe, not perforated pipe that leaks it back into the soil next to the house. Some low bids use corrugated perforated pipe because it is cheaper; the perforated pipe guide explains why that saves money now and costs it later.
The University Park requirement
University Park requires roof drainage to be piped through the curb or to the alley line, and a plan comes before the permit. That turns what could be a short run to an emitter into a line that crosses the front or back yard, often under a walk or drive, and ends in a cut through the curb or a connection at the alley. Each downspout can still sit within or near the national range when several share one trunk line, but the curb or alley connection and its permitting are added work. Side-yard grade there is also capped at 5 percent, which affects how pipe and surface water share narrow side yards. See University Park drainage.
Elsewhere, Coppell has issued residential curb cores for yard drains as engineering permits, one in 2022 for $100, and Grand Prairie bars concentrating runoff onto an adjacent lot. For Irving, we confirm the rule per address.
Two example layouts
These illustrations are built from the national budgeting range, not quotes.
| Layout | Scope | Illustrative budget |
|---|---|---|
| Two rear downspouts, lawn falls to the back fence | Shared trench to one pop-up emitter | About $300 to $700 |
| Four downspouts on a flat lot | Two shared trunk lines to a curb core | About $600 to $1,400, plus the curb core, any permit and concrete work |
Ways to keep it down
- Group downspouts by side of the house so each trunk serves two or three.
- Share an outlet with a nearby catch basin; both carry surface water in solid pipe.
- Plan the route around concrete where the slope allows.
- Fix gutters first so the downspouts are getting the water they should.
Next step
A useful estimate names each downspout, the pipe type and size, the outlet, any curb core or permit, and the restoration. For the bigger picture, see drainage cost in Irving and foundation drainage. Try the cost tool for a quick range, or send photos of each downspout for a written estimate.
Questions people ask
Does a larger roof section change the price of a buried downspout?
It can. A downspout draining a large roof section may need larger pipe and a bigger outlet to keep up with a heavy storm, which costs more than a short line from a small roof section.
What does a buried downspout price usually leave out?
Gutter repairs, a curb core and its permit, cutting a walk or driveway, and replacing more than a strip of sod are often extras. Ask whether each is included before comparing estimates.
Downspouts dumping at the slab?
Send a photo of each downspout and where the yard slopes, plus your address.