Water Routed Before It Causes Damage

Drainage & Erosion Excavation in Flagstaff for Properties With Pooling Water or Slope Washouts & Flagstaff, AZ

Longfellow Excavating LLC provides drainage and erosion excavation in Flagstaff for property owners dealing with standing water, washouts, or soil movement that threatens structures, driveways, or landscaping. You might see water pooling against your foundation after monsoon storms, runoff carving channels through your yard, or slopes losing soil every season, and you need grading and drainage solutions that redirect water before it undermines footings or damages paved surfaces.

We excavate swales, install French drains, regrade slopes, and build retention or detention features to control stormwater runoff and prevent erosion. This includes shaping the ground to direct water away from buildings, stabilizing slopes with proper grading and material placement, and installing drainage pipe or rock channels where needed. The work accounts for soil type, slope angle, and how much water moves across your property during peak runoff events.

Reach out to schedule a site visit so we can assess drainage patterns and recommend grading or excavation that solves your water problems.

How We Redirect Water and Stabilize Slopes

We start by identifying where water enters your property, where it collects, and where it should exit without causing damage. Then we use excavators and graders to shape swales, cut drainage channels, or regrade slopes to a stable angle that resists erosion. For subsurface drainage, we trench and install perforated pipe wrapped in filter fabric and surrounded by drainage rock, then backfill and grade the surface to tie into the new system.

After the work is complete, you will notice that water no longer pools near your foundation, runoff flows predictably through designated channels, and slopes hold their shape during heavy rain instead of washing out. Driveways, patios, and landscaping stay intact because water is moving where it is supposed to go.

We can also build berms to divert water, install culverts under driveways, or create rock-lined channels where high-velocity runoff would otherwise erode bare soil. If your property drains toward a neighbor or public right-of-way, we coordinate outlet locations to meet local stormwater regulations and avoid creating new problems downstream.

Common Drainage and Erosion Questions

These questions cover the practical concerns that come up when property owners in Flagstaff are planning drainage improvements or erosion control work.

What is a swale and when do you need one?
A swale is a shallow, graded channel that moves surface water across your property without eroding the soil. You need one when water naturally flows across your land but has no defined path, or when runoff from uphill areas threatens to pool or wash out your driveway, foundation, or landscaping.
How do you prevent erosion on steep slopes?
We regrade slopes to a stable angle, usually three-to-one or gentler depending on soil type, and we can install terraces, berms, or rock channels to slow runoff velocity. In some cases, we place erosion control fabric or seed and mulch after grading to help vegetation establish before the next storm season.
What is the difference between a French drain and a surface swale?
A French drain is a subsurface trench filled with drainage rock and perforated pipe that collects and moves groundwater, while a surface swale is a graded channel that directs runoff across the ground. You use a French drain when water is seeping up or pooling below the surface, and a swale when runoff flows across the top.
How do you handle drainage near a foundation?
We grade the soil to slope away from the foundation at least six inches over the first ten feet, and we can install a perimeter drain if water is seeping through the footing or basement wall. The goal is to move both surface runoff and subsurface water away from the structure before it causes moisture damage or settling.
Can you tie drainage work into an existing stormwater system?
Yes, we can connect new swales, drains, or culverts to your existing system or to a natural drainage corridor if one is available. In Flagstaff, many properties drain into washes or forest service land, and we coordinate outlet locations to avoid erosion or violations of local stormwater rules.

If water is pooling, eroding, or threatening your property, contact Longfellow Excavating LLC to assess your drainage needs and plan excavation that protects your investment and keeps runoff under control.