Linear Trench Drain




Linear Trench Drains are prefabricated drains placed vertically within pavement to intercept and remove water from the pavement surface. They consist of a Linear Trench Drain encased with concrete and capped with a certified casting as per Standard Road Plan SW-521. They function like an intake for water on the pavement surface under potential driving lanes. Linear Trench Drains requires a trench for placement within the concrete encasements with dimensions as specified by each manufacturer of the Linear Trench Drain and the standard road plan.


Linear Trench Drains are used in various locations including high speed crossovers and crossovers at intersections.


Details of Linear Trench Drain placement are shown on Standard Road Plan SW-521.


Linear Trench Drains shall meet the requirements of Article 2435 and 4149.05 of the specifications.



Application for approval shall be sent to the Methods Engineer in the Iowa DOT’s Office of Design (515-239-1402). All product manuals, specifications and brochures along with correspondence indicating compliance with the Specifications for Linear Trench Drain shall be submitted. Samples of materials may also be requested. The Methods Engineer will evaluate the application and determine whether the product is to be approved.


Casting certified for 40,000 pound proof-load according to AASHTO M 306



Acceptance of Linear Trench Drains shall be based on approved source and a certification statement. Approved sources are listed in the Materials Approved Products Listing Enterprise (MAPLE)



Shipments to projects shall be accompanied by bill of lading and certificate of compliance with the following information:


1.   Fabricator Name

2.   Certification Statement

3.   Signature of Authorized Person

4.   County, Project Number and Contract Number


“It is hereby certified that the trench drain listed was manufactured to meet the applicable requirements of the Iowa Department of Transportation and the requirements of the ASTM. We also certify that any steel or iron used to fabricate this material meets the requirement of IM 107 Group 2, Buy America.