St. Louis Drainage Cost Guide

Understand the factors that drive drainage project cost in St. Louis and use our planning estimator for common drainage solutions.

Reviewed and updated September 20, 2026

Why prices vary

Drainage work can range from routing a downspout to excavating and restoring a long drainage corridor. Scope matters more than a single citywide average.

Main cost drivers

System type and distance.
Excavation depth and soil.
Access.
Inlets, basins, and transitions.
Outlet location.
Utilities and hardscape crossings.
Restoration.

Try the estimator

Use the calculator for a rough planning range.

Open Cost Estimator

Questions homeowners often ask

Can I diagnose this from photos alone?

Photos can help show symptoms, but slope, elevation, soil, discharge options, utilities, and rainfall behavior may require an on-site evaluation.

Should I get more than one estimate?

For meaningful drainage work, comparing scope—not just price—can be useful. Ask each provider what problem they believe they are solving and where the water will ultimately go.

Who should verify permits?

Ask the provider who will be responsible for checking and obtaining any permits or approvals required for the specific property and scope.

Educational information, not a diagnosis.

Drainage design depends on site conditions. Use the estimator for planning or request an on-site assessment from an independent provider.