FLOOD06285

• County: Mesa
• Community: Grand Junction
• Stream Name: Colorado River
• Basin: Colorado Mainstem
• Title: Grand Junction Riverfront Development
• Date: 4/1/1992
• Prepared For: State of Colorado
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

. Procedures for FEMA consideration of alternate
freeboard, (onus of demonstrating variance adequacy is
on owner; documentation of analysis must be submitted
to and approved by FEMA).

. Exclusion of human intervention to meet level of
protection requirements (no artificial capping such as
earthfill on top of levees allowed; operation of
closure structures subject to conditions outlined by
FEMA).

. Interior drainage (must be demonstrated to be
adequate).

. Procedures for obtaining credit for levee systems
(requires Federal Insurance Administration review of
as-built specifications, and specifications ~ust adhere
to requirements stated above and to theCor~s
standards).

other guidelines considered in this study are contained in
ER 500-1-1, which describes eligibility of non-Federal levees for
rehabilitation under Public Law 84-99.

It is important to note that an assessment using the
detailed application of the above criteria is beyond the scope of
this inventory. Each river levee site has its own specific
conditions that require special considerations for analysis of
adequacy. Therefore, the information developed during this
inventory can be used to confidently determine only a few of the
factors which might exclude levees from FEMA crediting.

b. Field Methods. - Locations of the levee segments were
annotated on topographic maps of the Colorado River between
Palisade and Lorna. Existing ground elevations by the levees were
determined from the maps, as were the loo-year flood elevations
and stationing. The field inspection information, along with
office-derived data, is presented on inspection sheets provided
in Appendix B.

Topographic maps were obtained from mapping used for the
revision of the FEMA Flood Insurance study and flood plain
delineations in the Grand Valley. These maps, included in
Appendix C, are preliminary and used with permission of
Region VIII of FEMA. The water surface profiles are those used
for the FEMA study (see paragraph 4) and are included in
Appendix D.

The inspection sheets in Appendix B provide the following
detailed information about each levee system:

. Location by stationing

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