Real assessment example

What a professional yard drainage assessment looks like

Two problem areas around one Dallas–Fort Worth home were documented, explained and organized into one connected drainage plan.

Residential side yard and patio evaluated during a Dallas–Fort Worth drainage assessment — Area 1 overview used to evaluate the relationship between the house, paved surface, roof runoff and existing collection points.

Start with the water path

A useful estimate should explain more than where a drain might go.

A good yard drainage assessment identifies where the water comes from, why it remains, how the surrounding grade controls its movement and where the collected water can be discharged. In this example, the property had two visibly different problem areas, but both lacked a reliable route away from the house.

The proposed layout treated the property as a connected system instead of recommending isolated products. Surface grading, catch basins, roof runoff, solid pipe and the existing outlet all had to work together.

Problem area 1

Water remaining near the foundation

The first area already had catch basins, but their location and the surrounding surface did not create dependable drainage away from the house.

What the assessment found

The existing collection points were too close to the foundation to establish a useful surface slope away from the structure. The ground was uneven, and runoff from the surrounding property did not have a consistent path through the area.

Roof water was also being released from the downspout directly onto the ground and nearby paved surfaces. During rain, that concentrated flow could repeatedly saturate soil beside the house instead of entering a controlled underground line.

The puddle was the visible symptom. The larger concern was repeated moisture beside the foundation, especially where North Texas soil can expand, shrink and erode as its moisture content changes.

Proposed Area 1 scope

Move, collect and convey

Position three 12-by-12-inch catch basins approximately two to three feet from the foundation.
Connect one 4-inch downspout directly to the underground drainage system.
Use solid 4-inch pipe for the conveyance route.
Remove soil from the high section where needed and regrade away from the house.
Maintain approximately 1% fall toward the existing outlet, subject to field verification.

Catch basin positioned beside a residential foundation in a graded soil strip — Assessment reference: surface collection beside the foundation must work with the surrounding grade and underground route.

Two catch basins set into a restored residential lawn beside a house — Installation reference included in the estimate to show discreet surface inlets after restoration.

Annotated proposed drainage layout showing catch basins, underground pipe and grading arrows — Proposed Area 1 layout: move collection away from the house, connect the downspout and route water toward the existing outlet.

Current and corrected grading diagrams comparing drainage toward a foundation with drainage away from it — The estimate explained the grading principle visually: establish positive drainage away from the foundation and direct water toward the collection points.

Problem area 2

No consistent slope or functional drainage path

The second area had no dependable collection points, controlled low line or underground route, so water entering the space had nowhere reliable to go.

Narrow outdoor area between a covered patio and fence evaluated for standing water — Area 2 condition near the patio: a confined space with no dependable low point or collection system.

Narrow side yard with stepping stones and uneven ground evaluated for a central drainage route — The central corridor was reviewed as the practical low route for surface collection and buried conveyance.

Long residential side yard evaluated as a route to an existing drainage system — The route toward the existing drainage system had to be considered together with pipe length, fall and restoration.

Why one drain would not be enough

Water must first be directed to a collection point. A catch basin placed in an arbitrary location cannot correct an uneven surface that sends water in several directions. The buried line also needs continuous fall and a suitable outlet.

In this area, roof runoff and runoff entering from beyond the immediate yard added water to an already flat, confined space. Without coordinated grading, collection and conveyance, standing water could continue even after a single inlet was installed.

Proposed Area 2 scope

Create a controlled center route

Install six 9-by-9-inch catch basins along a controlled central low point.
Connect two 4-inch downspouts directly to the underground system.
Run approximately 145 linear feet of solid 4-inch pipe to the existing drainage system.
Regrade the area so the foundation and fence sides remain higher than the center route.
Create approximately 1% fall toward the basins where field conditions allow.

Landscaped side yard with stepping stones and multiple surface catch basins — Installation reference included in the estimate to show how several inlets can follow a controlled central low point.

Annotated Area 2 drainage plan showing six catch basins, downspout connections and underground pipe route — Proposed Area 2 layout: six collection points, two downspout connections and a solid underground route to the existing system.

Why the scope was not reduced

The simplest complete solution is not always the smallest list of materials.

Several approaches were considered while the estimate was being prepared. A more expensive alternative was removed because it did not offer a better practical result. Reducing the remaining scope was not recommended because each component had a separate job.

Grading directs water. Catch basins collect it. Downspout connections control concentrated roof runoff. Solid pipe carries the collected water, and the outlet completes the route. Removing one of those pieces could leave part of the original problem unresolved.

What this example demonstrates

Similar puddles can require different drainage details.

Trace every input

Roof discharge, neighboring runoff, pavement and natural surface flow can all contribute water to the same low area.

Measure the grade

Collection points work only when the surrounding surface and underground line can move water toward them and onward.

Confirm the outlet

A proposed drain is incomplete until the full route reaches a suitable, maintainable discharge point.

If water remains beside your foundation, between homes, around a patio or in the same low part of the yard after each rain, an on-site assessment can identify the likely cause and show how the proposed system is intended to function before installation begins.

Need a property-specific plan?

See what is included in an on-site drainage assessment.

Learn about our property drainage assessments

This page presents an example of a completed drainage assessment and proposed layout. It does not represent a completed installation. Client-identifying information and pricing have been removed. Installation-reference photographs shown in the original assessment are labeled in their captions.