Salmon Habitat ELWd

Functional performance of engineered LWD for fish and wildlife habitat enhancement


An engineered large woody debris structure has been designed and developed for use in habitat and watershed restoration projects. The ELWd® structure was designed according to the Appreciative Design method to accommodate readily available wood materials, low-tech manufacturing methods, and volunteer-based installation. Technical features include a high organic surface area, structural integrity in an all-wood product, length proportional to channel properties and diameter proportional to flow depth. Equations for appropriate structure length and diameter as functions of channel properties were derived from the literature. The ELWd® structures have now been installed to provide a number of different functionalities including: scour pool formation, complex cover features, bank protection, flow routing, sediment storage and high flow refuge. The paper describes the design rationale and critical assumptions that resulted in the present configuration for ELWd® structures, and results of the first three years of in-stream use.

About the Publication 

Dooley, J.H., K.M. Paulson, J.T. Maschhoff, and K.R. Chisholm. 2000. Functional performance of engineered LWD for fish and wildlife habitat enhancement. ASAE Paper PNW2000-06. St. Joseph, MI: American Society of Agricultural Engineers.

Read the full article in PDF format: