Last fall, in August of 2025, the Illinois DOT ‘Bureau of Design and Environment’ announced that all Erosion Control Blankets used on IDOT projects must have a “natural fiber net” (or Leno-weave), thereby eliminating the use of plastic-netted erosion control blanket.  To carry out this change, revisions were made to Section’s 41 and 59 of their BDE Manual which included:

1. the removal the Heavy Duty ECB pay item and,
2. revised the remaining Pay Item to be defined as “bionet or EC Blanket-products containing a “leno weave net with moveable joints.”

This will ensure that their projects are both wildlife friendly and more friendly to humanity.

This announcement came on the heels of a research Study from the University of Illinois Urbana-Champaign, completed in 2023, which evaluated bio-net performance and showed equivalency. Also, the Illinois Tollway has an ongoing study to look at the environmental effects of microplastics in the environment from the breakdown of plastic-netted blankets. For this research, Northern Illinois University will be using cutting edge technology to detect microplastics in stormwater. Similar actions have been taken by other State Transportation Departments recently, but mostly by internal guidance as there is no Federal Directive or ban on plastic netted products (only advisory guidance from the U.S. Fish & Wildlife Service at this time).

IDOT BDE Procedure Memo – Manual Revision Chapters 41 and 59 related to BDE Special Provision Erosion Control Blanket (ECB) Aug 2025

ICOT Evaluation of Net-Free Erosion Control Blankets Nov 2023

ECB with plastic net        Leno weave natural bio-net