Elastomeric drainage troughs and side curtains shall be durometer (50 to 60) and synthetic fabric reinforced. Thickness of the side curtains and the reinforced neoprene trough should be 1/4-inch. The elastomeric compound for trough and curtains shall be in accordance with Table 4195.02-2 of Article 4195.02 of the Standard Specifications, except the tensile strength shall be 1500 psi (10.3 MPa) minimum or it shall be Ethylene Propylene Diene Monomer (EPDM) (ASTM D 2000, Line call outs 3BA, 515, A14, B13, F17, C12, and K21). The troughs and curtains shall meet the requirements of applicable Iowa Department of Transportation Specifications.




Acceptance of elastomeric drainage troughs and side curtains for use on Iowa Department of Transportation projects is based on manufacturer and brand name approval. The material delivery invoice to the project must identify the manufacturer and brand name of the product being used.


Approved manufacturers and brand names are listed in Appendix A.




To obtain approval, the manufacturer shall submit the following to the Office of Materials in Ames, Iowa:


1.   Product identification

2.   Technical information on the use of the product

3.   A Material Safety Data Sheet (MSDS)

4.   A representative sample of the material approximately 3 square feet  (0.3 square meter) in area




In order to maintain approved status, the manufacturer shall file a certification at the beginning of each calendar year stating that the material supplied during that year is identical with the product previously tested and approved by the Office of Materials.




The Office of Materials may sample at the job site, supplier, or source and test to verify compliance with the specifications. The Office of Materials will notify the appropriate District Materials Office when samples are to be obtained.