Custom-made Hancor HDPE culverts save the fish on Oregon's coast.

Hancor assists in another environmentally-friendly project

Clatsop County , OR, November, 2003 — The engineering technician in this coastal Oregon county knew exactly the kind of pipe he needed for an environmentally-sensitive culvert replacement last fall.

The state’s fish and wildlife division classified two of the 15 waterways they were paving over as fish streams. That meant corrugated pipe had to be installed as part of the Division of State Lands Permit. Sounded easy enough.

Here’s the catch – the exact pipe he needed didn’t exist…yet.

Terry Hendryx, an engineering technician with the Clatsop County Public Works Department, had three criteria the pipe must meet – corrugations on the inside of the pipe, a diameter of 48 inches and a non-corrosive pipe material.

Single wall pipe at that size is readily found in corrugated metal, but the Public Works Department stopped using metal pipe 10 years ago due to its lack of projected longevity and because HDPE is much lighter in weight.

“For the last 10 years we’ve been converting all our culverts to high-density polyethylene (HDPE),” Hendryx said. “The pH factors and saline levels in our water destroy the metal pipes after just 15 or 20 years. Looking at the HDPE pipe we put in 10 years ago, there is no damage at all. With the expense and the regulatory hoops we have to jump through to complete a project, why replace pipe that often if you don’t have to?”

Since single-wall corrugated HDPE isn’t made in diameters over 24 inches, Hendryx approached Hancor with a creative solution.

Hendryx submitted a design to Hancor that included placing 1½-inch to 2-inch baffles on 2-foot centers on the bottom of the 48-inch dual-wall Sure-Lok pipe. The baffles were cut from ½-inch thick HDPE flat stock pipe, fit to the bottom of the culvert and welded into place. During the first week of September, the design was approved by the Oregon Department of Fish & Wildlife’s (ODF&W) local biologist in charge of the project.

Smaller fish can only swim continuously upstream against a maximum current of 2 mph. Rock was required to be placed in the culvert to simulate a natural streambed, and the baffles were needed to help hold the rock in place. During high-velocity flow times, fish use the pools and eddies that the rocks create as hiding and resting areas until the current slows down.

Hancor embraced the idea. Six days later, pipe arrived in Clatsop County. “The quick turnaround was important because the ODF&W has a September 15 cutoff date for all in-water work,” Hendryx said.

The entire project spans 2¼ miles of county road and calls for about 70 feet of Hancor’s Sure-Lok^® F477 HDPE pipe, 65 feet of 30-inch and 700 feet of 18-inch pipe. Sure-Lok pipe is available in diameters up to 60 inches. Besides culverts, other applications include storm sewers, parking lot drainage, retention/detention, culverts/cross drains, slope drains/edge drains, mining/forestry, industrial, pond overflow, playing fields and golf course drainage.

“We’ve received several heavy rain events since installation, and the ribs Hancor welded in are holding the rocks sufficiently,” Hendryx said.

Go fish.

About Hancor
One of the nation’s largest suppliers of storm water management systems, Hancor manufactures a wide variety of plastic drainage products for the commercial, residential, construction and agricultural markets. Hancor was founded in 1887 in Findlay, OH and operates manufacturing facilities and service centers across the country.

For more information, please contact:

Ms. Tori Durliat, Hancor, Inc.
Marketing Communications Manager
401 Olive Street,
Findlay, Ohio 45840
Phone: 1-800-537-9520
Fax: 1-419-424-8302
E-mail: tdurliat@hancor.com