DESIGN MEMORANDUM NO. 5-99

TO:                                           Chief District Engineers
                                                  Active Consultants
                                                  Construction Engineers

FROM:                                     John B. Sacksteder, P.E.
                                                  Director, Division of Highway Design

                                                  Dexter Newman
                                                  Director, Division of Construction

DATE:                                      July 8, 1999

SUBJECT:                               Temporary Barrier Wall

The "AASHTO-FHWA Agreement on the NCHRP 350 Implementation" requires an approved temporary barrier wall to be used by October 2000. We have developed a new temporary wall design (TYPE 9T) that is based on the approved Iowa Pin and Loop Design.

The FHWA has agreed that our current stockpiles of temporary barrier wall may continue to be used through October 2004. This agreement requires any new wall that will be acquired to be the new Type 9T wall. Projects needing temporary barrier wall should call for bid item "CONC BARRIER WALL TYPE 9T" Code No. 3171. The current Concrete Barrier Wall Types L and M shall be acceptable substitutes if available from existing inventories.

The attached Concrete Barrier Type 9T drawing has been placed on the Sepia List and full size reproducible are available from the Standard Drawing Section of the Division of Highway Design. This will be added to the Standard Drawings with the next revision.

JBS:DN:WSG:jq

Attachment:  General Summary