specifications

Frequently Asked Questions

What is the ERL?

The Electronic Reference Library (ERL) is a collection of manuals produced by the Iowa DOT. The ERL includes:

  • Standard Specifications for Highway and Bridge Construction with the General Supplemental Specifications incorporated in redline and strikeout
  • Supplemental Specifications
  • Standard Road Plans, Standard Culvert Plans, Standard Bridge Plans, and Sign Truss Standards
  • The Construction Manual
  • Materials Instructional Memorandums (IMs)
  • The Flagger Handbook
  • Statewide Urban Design and Specifications (SUDAS)

The ERL can be viewed on a browser, and all references are hyperlinked.

How often is the ERL revised?

Twice each year in conjunction with the April and October highway and bridge construction lettings.

How often is the General Supplemental Specifications revised?

Twice each year in conjunction with the April and October highway and bridge construction lettings.

How can I obtain a copy of the most recent updates to the Standard Specifications 2009 Book?

Obtain a copy of the General Supplemental Specifications (GS).

How can I obtain the latest version of the ERL (Electronic Reference Library)?

Order the latest version of the ERL. Fill in the appropriate information.

How can I obtain a copy of the current General Supplemental Specifications book?

Receive a printed copy of the GS.