Summary: Revision to 
Figure D.2.8-3, Wave 
Runup Guidance for 
Vertical Wall, From 
Shore Protectional 
Manual (USACE, 1984) 

Audience 

This procedure memorandum is intended for use by all users of the current 
Appendix D of the Guidelines and Specifications for Flood Hazard Mapping 
Partners, the Atlantic Ocean and Gulf of Mexico Coastal Guidelines Update, Final 
Draft, February 2007. 

Purpose 

The purpose of this procedure memorandum is to redefine and correct an error for 
a coefficient for relative structure depth used in Figure D.2.8-3 presented in 
Appendix D of the Guidelines and Specifications for Flood Hazard Mapping 
Partners, the Atlantic Ocean and Gulf of Mexico Coastal Guidelines Update, Final 
Draft, February 2007. This revision corrects Figure D.2.8-3 so that it is consistent 
with the U.S. Army Corps of Engineers 1984 Shore Protection Manual figure from 
which it was derived. 

The procedure for estimating wave runup on vertical structures relies on the use of 
Figure D.2.8-3, provided the wave steepness and the depth at the toe of the 
structure. The curves presented in the study guidelines enable the estimation of 
wave runup on vertical structures given the wave steepness and relative structure 
depth. The uppermost curve previously was assigned a coefficient of 0.60 and is 
changed to 1.50 with this procedure memorandum, for consistency with the Shore 
Protection Manual. Example figures and the redefined figure are included in the 
procedure memorandum. 

For all new detailed coastal study starts in Fiscal Year 2010 making use of this 
procedure for estimating wave runup on vertical structures, the coefficient for 
structure depth is redefined. Letters of map revision submitted for studies 
completed prior to issuance of this procedure memorandum will use the redefined 
coefficient. A corrected Figure D.2.8-3 is included in the procedure memorandum. 

Risk MAP Guidance 

This document is a component of 
Risk MAP Guidance. The Risk MAP 
program is managed by FEMA to 
develop flood risk information and 
work with communities to help 
them understand and act on the 
data to manage the risks. Risk 
MAP Guidance defines the product 
and process standards and best 
practices for the program: 

. 
Standards are contained in 
the document “Guidelines 
and Standards for Flood 
Risk Analysis and Mapping” 
(G&S document) which 
primarily contain standards, 
but currently substantial 
best practice information 
are also included. 

. 
Procedure Memos 
supersede portions of the 
G&S document or address 
new issues not currently 
covered. In most cases they 
will be integrated into the 
G&S document over time. 

. 
Operating Guidance 
describes best practices 
that support the Risk MAP 
standards. 


December 2011 
www.fema.gov/plan/prevent/fhm/rm_main.shtm · 1–877–FEMA MAP