Improvements in the Floodway
Improvements within the floodway are limited or are not permitted unless the improvement is independently evaluated through hydraulic modeling by a registered professional engineer and a "No Rise" certificate is completed.
- The "No Rise" certificate ensures there will be no floodway impact (no increase to the 100-year flood stage) as a result of the improvement.
- All activities in the Floodway are regulated by Title 10, Chapter 17, Article B of the City Code and most require the issuance of the Conditional Use Permit after consideration by the Planning Commission and City Council.
- Geotechnical evaluation of the site may be required based on lot specific criteria.
Improvements in the Floodplain
Essentially all construction activities (e.g. excavation and/or fill) and improvements (e.g. fences, structures, building additions, remodeling, levees, and flood-walls) made on private property in the floodplain require a Floodplain Development Permit. As part of permit issuance:
- The location and type of improvement proposed must be evaluated.
- If the improvement encroaches within the recommended geotechnical setback (area at risk of riverbank stability failures), additional detailed geotechnical analysis may be required or recommended prior to permit issuance.
- If substantial improvements to a non-conforming building are proposed, the building may need to comply with current floodplain building standards.
A Floodplain Development Permit is required if a new structure or addition to an existing structure is proposed within FEMA’s SFHA (even if the property is covered by a LOMA or LOMR-F). In certain situations, a Provisional Use Permit or Conditional Use Permit may also be required.
If the improvements include a basement, flood-proof construction standards apply and are implemented as follows:
- A Floodplain Development Permit application must be submitted. The City will provide the minimum foundation elevation and maximum basement depth to comply with FEMA standards.
- Building plans and as-builts must be prepared and certified by a professional engineer or professional architect in the State of Minnesota and must incorporate flood-proof construction standards.
- Two sets of construction plans must be submitted and must clearly show flood-proofing details, including minimum and maximum elevation requirements.
- After plan approval, the City will issue a Floodplain Development Permit. No construction can commence until the permit is issued.
- An elevation stake is supplied by the Engineering department for construction purposes. This elevation should be verified, prior to construction, by the engineer or architect hired to certify the improvement.
- When construction is complete, the requester must submit required building inspection forms, as-built plans, and a FEMA Elevation Certificate to the City.
Floodproof Construction Requirements
For lots in the SFHA (100-year floodplain) or lots with an approved FEMA Letter of Map Revision Based on Fill (LOMR-F) the flood-proof construction requirements must be followed.
Email Floodplain staff or call 218.299.5386.