Minnesota
Detention and Retention Pond Design
Design of detention basins, retention ponds, underground storage and outlet structures to control runoff.
What the work involves
Detention basins temporarily store runoff and release it slowly; retention ponds hold a permanent pool. The engineer sizes storage, designs outlet structures and emergency spillways, checks soils for infiltration or liners, and provides maintenance guidance. Underground chambers are used where land is costly. Failing or silted ponds may need a redesign or retrofit.
Local conditions we plan for
- Deep frost penetration and frost heave
- Heavy snow loads
- Riverine and spring snowmelt flooding (Red River)
- Peat and soft organic soils
Building code: 2018 IBC/IRC adopted at the state level (ICC adoption chart, April 2026).
When you need it
- Development requires peak flow control
- Limited space requiring underground detention
- Existing pond is silted, eroding or overflowing
- HOA or owner needs pond maintenance or retrofit plan
- Pond embankment shows seepage or slumping
Frequently asked questions
How much does detention and Retention Pond Design cost?
Across the US, detention and Retention Pond Design usually costs $5,000 to $50,000. Estimate. Underground systems and dam-safety-regulated embankments cost more.
How long does detention and Retention Pond Design take?
Plan on 3 to 10 weeks from signed proposal to stamped deliverables, longer if a site visit, soil testing or a permit review cycle is involved.
Do I need a licensed PE for detention and Retention Pond Design?
In most US jurisdictions, yes. When the work needs a permit, the plans, calculations or report usually must be sealed by a Professional Engineer licensed in the state where the project is located. Every deliverable we issue for permit is sealed that way.
How do I verify an engineer's license in Minnesota?
Engineers practicing in Minnesota are licensed by the Minnesota Board of Architecture, Engineering, Land Surveying, Landscape Architecture, Geoscience and Interior Design (AELSLAGID). You can confirm a license number and its status in the board's public license search before you sign a contract.
How deep is the frost line in Minnesota?
Minnesota Rule 1303.1600 sets minimum footing depth for frost protection at 60 inches in Zone I (northern counties) and 42 inches in Zone II (southern and metro counties), unless an engineer competent. Local building departments set the required footing depth, so confirm the exact figure for your county before designing foundations or retaining walls.
Which building code applies in Minnesota?
2018 IBC/IRC adopted at the state level (ICC adoption chart, April 2026). Cities and counties can add local amendments, which is one reason to hire an engineer who works in your area.