At this time ISWS is unable to receive hard copy LOMR/CLOMR applications due to the COVID-19 outbreak and the State's Stay-at-Home order. Any hard copy submittals mailed to ISWS recently will not be received until the Stay-at-Home order is lifted. If you have not received formal acknowledgement of your recently mailed request, please contact Chris Hanstad (contact info below) to inquire the status of your submittal.

If you wish to make a LOMR/CLOMR application submittal to ISWS during this time, you must make it via FEMA's online LOMC portal: You must register for a free account. When logged in, please select "Create Revision Application" to start your LOMR/CLOMR application. Follow the prompts to upload all of your application documentation. Once your online application is complete, ISWS will promptly begin reviewing and processing your application as normal. Thank you for your understanding.

LOMR/CLOMR Processing

On September 1, 2010, the Illinois State Water Survey began reviewing applications for Letters of Map Revision (LOMR) and Conditional Letters of Map Revision (CLOMR) as part of FEMA's LOMR Delegation program. Currently, Illinois is one of only three statewide participants in the program. Through the LOMR Delegation program ISWS now has review authority for all MT-2 (LOMR/CLOMR) applications within the State of Illinois.


ISWS reviewers have developed checklists as part of the MT-2 review process. These checklists are available for applicants to QA/QC their own models using the same criteria that the MT-2 reviewers use. The checklists are not fully comprehensive and do not guarantee acceptance of an MT-2 submittal.

  • Initial Inventory - This checklist identifies the items required to initiate a LOMR/CLOMR review.
  • Hydrology Review - This document covers several hydrologic methodologies and lists the common data elements needed to complete a hydrologic review.
  • Hydraulic Review - This checklist is designed to identify common hydraulic modeling errors or issues. The checklist is most applicable to steady state HEC-RAS models, but can be used in some capacity for other hydraulic models.

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Chris Hanstad, PE, CFM
Illinois State Water Survey
2204 Griffith Drive
Champaign, IL 61820
(217) 244-3372