Drainage & Grading Solutions
Grading corrections, French drains, and surface water solutions built for expansive Front Range clay.
What this work involves
Water is the enemy of every foundation on Denver Blue clay, and most drainage problems we get called out for aren't exotic — they're a downspout dumping four feet from the house, a patio that slopes the wrong way, or a window well that fills like a bathtub every time it rains. Fixing the symptom without fixing the grade just means we're back in two years for the same complaint.
Our drainage work starts with figuring out where the water is actually coming from and where it wants to go, not just where it's currently pooling. That usually means walking the property after a rain if we can, checking gutter and downspout locations against grade, and sometimes running a hose test to watch water move in real time. From there we design the fix — regrading, a French drain, a curtain drain, or a combination — sized to the actual watershed hitting that spot, not a generic pipe-and-gravel trench.
This work matters more here than in most parts of the country because our clay soils don't just get soggy, they swell. A foundation that sits in saturated bentonite clay through a wet spring can heave enough to crack drywall and jam doors, and that damage is far more expensive to fix than the drainage correction that would have prevented it.
What is included
- On-site water tracing and diagnosis
- Grading design to shed water at proper slope from the foundation
- French or curtain drain installation with washed rock and filter fabric
- Catch basin and area drain installation at low points
- Downspout tie-in and extension to the drainage system
- Compacted backfill and surface restoration
- Confirmation of a compliant, non-nuisance discharge point
What you get out of it
Diagnosis before digging
We trace water to its source instead of guessing, which means the fix addresses the actual problem instead of moving it somewhere else on the lot.
Built for clay, not sand
Our drain designs account for the slow percolation rate of Front Range clay, which behaves very differently than the sandy soils most generic drainage advice assumes.
Protects the foundation investment
Correcting grade and drainage is a fraction of the cost of underpinning or foundation repair after clay heave damage.
Works with your landscaping
Drain lines and grading changes are designed to tie into existing beds, patios, and irrigation rather than requiring a full landscape teardown.
Respects downstream neighbors
We design discharge points that don't just dump your water problem onto the property next door, which keeps you clear of nuisance disputes.
How we run the job
- 01
Site assessment
We walk the property, review grading history if available, and identify every contributing source: roof runoff, surface sheet flow, and subsurface seepage.
- 02
Water tracing
Hose tests or observation during rain events confirm where water actually collects and which direction it needs to be redirected.
- 03
Design and permitting
We size pipe, select a discharge point, and confirm the plan doesn't concentrate flow onto a neighboring property or violate county drainage easements.
- 04
Excavation
Trenches for French or curtain drains are cut to the design slope, typically a minimum 1% grade toward the outlet.
- 05
Drain installation
Perforated pipe wrapped in filter fabric is bedded in washed rock, with solid pipe used for any section running under a walkway or driveway.
- 06
Backfill and compaction
Fabric wraps the aggregate to keep fines from clogging the system, then backfill goes in compacted so the surface doesn't settle later.
- 07
Final grading and sod or mulch restoration
Surface grade is reestablished to shed water away from the foundation at a minimum 5% slope for the first 10 feet, and disturbed areas are restored.
How long it takes
- 1 day
- Downspout extensions, simple regrading of a small problem area, or a short surface swale.
- 2–3 days
- A single French drain run of 50–100 feet including excavation, pipe, and backfill.
- 3–5 days
- Whole-lot regrading combined with a perimeter French drain system.
- 1–2 weeks
- Larger properties requiring curtain drains, dry wells, and coordinated hardscape tie-ins.
What moves the price
- Trench length and depth
- Longer runs and deeper trenches around walkout basements mean more excavation and spoil disposal.
- Number of collection points
- Multiple downspouts, window wells, and low spots each add a connection to the system, increasing pipe and fitting costs.
- Available outlet
- A lot with a natural slope to daylight is far cheaper to drain than a flat lot needing a sump pump or dry well.
- Hardscape crossings
- Running a drain line under an existing patio, driveway, or sidewalk means cutting and patching that surface, which adds cost.
- Regrading scope
- Correcting years of settled or improperly graded soil around a foundation takes more material and compaction effort than a simple new drain trench.
Specifications that hold up in Colorado
Perforated PVC drain pipe
4-inch perforated pipe for collection runs, transitioning to solid pipe at the discharge point and under any hard surface crossing.
Washed drain rock
3/4-inch washed rock free of fines surrounds the pipe so water moves freely instead of the aggregate clogging with clay silt over time.
Non-woven filter fabric
Wraps the rock-and-pipe assembly to keep migrating clay fines from filling the voids and choking the drain within a few seasons.
Catch basins and area drains
Cast iron or heavy-duty plastic grates at low points collect surface sheet flow before it can pond against a foundation or patio.
Dry wells and discharge chambers
Used where there's no viable gravity outlet to daylight, sized to the contributing drainage area and local infiltration rate.
Colorado considerations
Denver Blue clay and Pierre Shale expand significantly when saturated, and a poorly drained foundation perimeter is the most common cause of the heave cracking we get called to diagnose. Keeping water moving away from the foundation, not just off the surface, is the whole point of a properly designed system here.
Colorado water law limits large-scale stormwater capture and reuse under state water rights statutes, so residential drainage systems here are designed to convey water to an approved discharge point rather than build large storage cisterns the way some other states allow — we design within those rules rather than promise rainwater harvesting we can't legally deliver at scale.
Spring runoff off the foothills and sudden summer monsoon downpours mean a system sized only for a light, steady rain will get overwhelmed. We size pipe and catch basins for a realistic peak event, not just average conditions.
Most Front Range counties require that regrading not concentrate or redirect water onto a neighboring lot, and some subdivisions have recorded drainage easements that restrict where you can outlet a system. We check plat and easement documents before finalizing a discharge point.
Project photos
Drainage & Grading Solutions FAQs
How do I know if I have a grading problem versus a drainage problem?
If water pools on the surface near your foundation or in the yard after rain, it's usually grading. If water is showing up in a basement or crawlspace without obvious surface pooling, you likely have a subsurface issue that needs a curtain drain, not just regrading.
Will a French drain actually work in our clay soil?
Yes, but it has to be designed for clay's slow percolation, meaning more reliance on gravity flow to a real outlet and less reliance on the soil absorbing water on its own the way it might in a sandier region.
Can you just dump the water onto the street or a neighbor's yard?
No. Most Front Range jurisdictions prohibit concentrating drainage onto neighboring property, and we design discharge points — street curb cuts, dry wells, or approved drainage easements — that keep you compliant.
Is a sump pump ever necessary for surface drainage?
On flat lots with no gravity outlet available, yes. We'll design a dry well and pump system only when a gravity solution genuinely isn't possible, since pumps add a maintenance and power-dependency element.
How much of my drainage problem is really a gutter problem?
More than people expect. A single downspout dumping at the foundation can saturate more soil than a whole yard's worth of surface sheet flow, so we always check gutter and downspout routing before designing a bigger system.
Do drainage corrections require a permit?
Simple regrading and downspout work typically don't, but larger grading changes or work that alters an easement or existing stormwater plan may need county sign-off, which we handle as part of the scope.
Related services
Excavation
Foundation excavation, utility trenching, and site grading built around Front Range clay, rock, and frost depth.
Retaining Walls
Segmental block, boulder, timber, and poured concrete retaining walls engineered for Front Range slopes and clay soils.
Landscaping
Paver hardscape, xeriscape planting, and grading work engineered for clay soils and Front Range water rules.
Start your drainage & grading solutions project
Tell us what you are planning. We walk the site, talk through what it actually takes, and send a line-item estimate you can read.