Promoting uniformity of urban design and construction across Iowa.


GFRP Dowel Bars

Due to supply problems with steel dowel bars and based on past research results, the Iowa DOT, SUDAS, Iowa Concrete Paving Association, and the CP Tech Center have developed provisional specifications for the use of glass fiber reinforced polymer (GFRP) dowel bars.  SUDAS Section 7010, 2.01, H calls for dowel bars to comply with Iowa DOT Section 4151.  The specifications allowing the use of GFRP dowels is now included in that DOT section.  The text of the modified specifications can be found hereNote the restriction on the 20 year design truck volume.  Check the Iowa DOT’s MAPLE system for approved products; those products should be added in the coming days.

Seeding Changes

Due to the current and anticipated seed shortages of Creeping Red Fescue, it is recommended that local agencies allow changes to the permanent and stabilizing urban seed mix until the end of 2021.  Proposed change is to allow a partial or full substitution of the required 25 lbs per acre of Creeping Red Fescue with any of the following varieties:

  • Chewing Fescue
  • Hard Fescue
  • Sheep’s Fescue
  • Blue Fescue

If this substitution is needed for projects, it should be addressed with a mutual benefit change order.

Due to a ryegrass crop failure last fall in Minnesota, it may be necessary to modify the rural area permanent seed rates on current contracts and other rural seeding applications in 2021.  Minnesota is the primary supplier of seed used in Iowa.  The Iowa DOT has suggested that for the 2021 construction season, the seed mixture can be modified by reducing the ryegrass to 30 pounds per acre if the fescue rate is increased to 150 pounds per acre.

Public Works Service Bureau

SUDAS staff has taken on the new adventure of creating a Public Works Service Bureau (PWSB). The PWSB provides a resource for public works staff members from cities of all sizes to connect with and learn from others how best to improve work efficiencies, learn new techniques, and maximize available resources.  Our goal is “communicate to innovate!”  Check out our new website to register and learn more.

2021 Edition Revisions

Remember, we do not print and mail revision packets anymore. Electronic versions of the 2021 Edition revision packets can be found under Design Manual -> Latest Design Revisions or Specifications Manual -> Latest Specifications Revisions.

Iowa DNR Review

The Iowa DNR Water Supply Engineering Section conducted a review of the 2021 Edition of SUDAS Specifications Divisions 3 and 5. In a letter addressed to SUDAS staff, Iowa DNR stated “at the current time, they are in accordance with the design standards of this Department and will be filed accordingly.”

Modifying the SUDAS Manuals

If you need to modify the SUDAS manuals to meet your jurisdiction’s needs, please read this document first.

SUDAS Email List

Anyone who would like to receive emails from us can subscribe to our list.

Temporary Traffic Control

SUDAS staff developed an updated Temporary Traffic Control Handbook through an Iowa Highway Research Board project. If you would like to request a copy, please complete this form. Click here for an electronic version of the handbook.

Potential Errors

If you notice something within the SUDAS Manuals that appears to be an error, please contact Beth Richards ( and let her know.