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