Get the latest updates!

Join more than 5,000 people receiving our monthly newsletter (Think Nilex!), invitations to events, seminars and webinars, and technical papers, case studies, special offers and more!


Enviro-Span Modular Culvert System

Gallery Specifications & MSDS Brochures & White Papers Installation & Design Contact Request a Quote


The Enviro-Span system is a modular culvert solution suitable for use over fish bearing or environmentally sensitive streams without disturbing the stream bed. Enviro-Span can be used in permanent and temporary applications. It is extremely easy to install due to its light weight, ease of handling, and elimination of cumbersome footings and fasteners for assembly. It is a clear span that requires minimal or no site preparation in temporary (or even semi-permanent) crossings.

Sensitive fish bearing and fish contributing streams can be crossed in any season as no excavation either in-stream or on stream banks is required for most crossings. Heavy equipment is at no time required to cross through the stream as all of the work can be done from one side until the fill is sufficient to cross over. Enviro-Span modules come as either straight or angled pieces, designed to follow the natural curves of a stream without requiring channelization.

Standard resource extraction road crossings can be completed from start to fully loaded truck traffic in as little as 3 hours.


Strong & Adaptable

The new materials technology used in Enviro-Span will handle as much or more static and dynamic loading as a competing conventional culvert. Perhaps more importantly, the inherent viscoelasticity of the material and use of compliant footings, will adapt when a road fill shifts or settles and places new stresses upon the structure. In conditions where older culvert materials often fail, Enviro-Span will interact dynamically with the fill (forming a composite soil arch) and simply readjust, somewhat like “smart” material technology. This property also allows Enviro Span arches to be placed under much deeper fills or to respond positively to soil movements (such as settling, frost heaving, or earthquakes) than culverts made of older and stiffer materials.

While Enviro-Span is far easier and less expensive to install than conventional arch culverts, its environmental assets are also highly desirable. The Department of Fisheries and Oceans in Canada and other major regulatory agencies in the United States, the USDA Forest Service and the EPA, are drafting and enforcing tougher stream crossing standards at this time. Conventional systems may no longer be adequate to meet these requirements without significant expensive modifications and installations. The Enviro-Span modular culvert system is ideal for use in situations that no longer allow the use of traditional, conventional culverts in fish bearing streams or other environmentally sensitive water crossings. To provide stream crossing options in as many site conditions as possible, production is being planned for a full range of additional sizes.


Specifications & MSDS

Brochures & White Papers

Installation & Design

Talk to Our Team

Want more information on our products and services? Need help with your order? Contact our team today.

With 38 years' experience in the geosynthetics industry and a long-standing commitment to the environment, our highly qualified staff can assess your needs and work with you to determine the best solution for the challenge you're facing.


Call: 303.766.2000

Request a Quote

Back to Top