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2 shown on submitted plans entitled "San Miguel Corridor Restoration Plan - Project Conditions Work Map," certified by Mr. Wolff on April 13, 2000, and "San Miguel Corridor Restoration Plan - Layout Plan" dated March 30, 2000; and as described in the report entitled "Application for Conditional Letter of Map Revision - San Miguel Corridor Restoration Plan, Telluride, Colorado," dated April, 2000, both prepared by Mussetter Engineering, Inc.; and the data listed below are received, a revision to the FIRM would be warranted. Because this revision request also affects the unincorporated areas of San Miguel County, a separate CLOMR for that community was issued on the same date as this CLOMR. The existing conditions model incorporates updated topographic information along the San Miguel River from approximately 300 feet downstream to approximately 3,100 feet upstream of Maple Street. Our review of the existing conditions model revealed that the elevations of the flood having a I-percent chance of being equaled or exceeded in any given year (base flood) increased in some areas and decreased in other areas along the San Miguel River compared to the Base Flood Elevations (BFEs) shown on the effective flood profile. The maximum increase in BFE, approximately 2.0 feet, occurs just upstream of Pine Street. The maximum decrease in BFE, 1.5 foot, occurs approximately 900 feet upstream of Maple Street. All increases are due to more detailed topographic information and natural changes to the existing stream channel. The proposed conditions HEC-2 hydraulic computer model incorporates the San Miguel River Corridor Restoration Project into the existing conditions model. Our review of this proposed conditions model revealed increases and decreases in BFEs when compared to the existing conditions model. The maximum increase in BFE, approximately 1.0 feet, will occur approximately 850 feet upstream of Maple Street. The maximum decrease in BFE, approximately 1.5 foot, will occurjust upstream of Maple Street. All affected property owners have been notified of the proposed increase in BFE and no insurable structures will be affected. Our review of the proposed conditions model revealed increases and decreases in BFEs along the revised reach of San Miguel River when compared to the effective conditions model. The maximum increase in BFE, approximately 1.5 foot, will occur just upstream of Pine Street. The maximum decrease, approximately 1.5 foot, will occur just upstream of Maple Street. The widths of the Special Flood Hazard Area (SFHA), the area that will be inundated by the base flood will increase and decrease compared to the effective SFHA. Our review of the proposed conditions model revealed that the width of the regulatory floodway will increase in some areas and decrease in other areas compared to the effective regulatory floodway width. The maximum increase in floodway width, approximately 50 feet, will occur at the confluence with Bear Creek. The maximum decrease in floodway width, approximately 90 feet, will occur at the Maple Street Bridge. Upon completion of the project, your community may submit the data listed below and request that we make a final determination on revising the effective FIRM and FIS report. . Detailed application and certification forms, which were used in processing this request, must be used for requesting final revisions to the maps. Therefore, when the map revision request for the area covered by this letter is submitted, Form I, entitled "Revision Requester and Community Official Form," must be included, (A copy of this form is enclosed,)