What a Drainage Estimate Should Include

A drainage estimate should explain both the symptom and the water path. If a proposal names a French drain or catch basin but does not explain where the water comes from and where it will go, the homeowner is being asked to approve a solution without a diagnosis.

Use this checklist to compare drainage proposals before approving trenching, grading, basin installation, or downspout work.

The estimate should name the diagnosis

• Surface runoff, roof runoff, subsurface saturation, low spots, or grading issues
• Where water currently collects and where it can safely discharge
• Whether the work affects lawn, patio edges, planting beds, irrigation, or utilities
• Which parts of the property will be restored after installation

Estimate drainage scope before reviewing proposals

Use this calculator to compare common drainage treatments before evaluating contractor estimates.

Drainage Cost Calculator

Estimate drainage project pricing for swales, French drains, and catch basin style systems.

Treatment length (linear ft)

Solution type Surface swale French drain Catch basin and pipe Downspout extensions

Access difficulty Easy access Standard access Difficult access

Restoration level Minimal restoration Standard restoration Heavy restoration

Outlet complexity Simple outlet Standard outlet Complex outlet

Estimate Drainage Cost Reset

Details that should be written down

• Drain type, length, depth, pipe, fabric, stone, basin, and outlet details
• Grading, soil removal, trench restoration, seed, sod, mulch, or hardscape repair
• Utility marking, permit assumptions, hidden condition exclusions, and warranty language
• What happens if the planned outlet is blocked, too shallow, or not allowed

Use this with Drainage Contractors Near Me and French Drain vs Surface Drain.