Beaver Dam Analogues (BDAs) Recipes

There are a large number of ways to construct beaver dam analogues. We are partial to those that take their inspiration most directly from beaver. In many places where beaver build dams, they do so successfully without posts driven vertically into the streambed. Our most common recipe for BDAs is the postless BDA shown above (Figure 4.32).

If you feel posts are necessary for temporary stability, we recommend first building a postless BDA and then installing posts afterward (see Figure 4.34).

Postless-BDA Recipe
Figure and construction details
Post-Assisted BDA Recipes
Figure and construction details

Some of the original and experimental BDA designs are described in Appendix C of Chapter 4. We do not usually recommend these early designs, as variations of the above tend to build more quickly and work better. However, they have still successfully promoted beaver dam activity in many cases and are included for your consideration.

We encourage practitioners to experiment with different recipes while adhering to the LTPBR Restoration Principles. For more details, see Chapter 4, or Module 5E on BDA construction.

Chapter 4: PALS & BDAs

Confusion about BDAs

In Module 2F, we talk about the many confusing uses of the term BDA and related terminology. Just because something is called a BDA does not mean it meets the LTPBR definition in Wheaton et al. (2019).

A BDA, per the LTPBR Standards of Practice, is a temporary structure meant to promote the process of beaver dam activity. BDAs can sometimes temporarily mimic beaver dams to, for example, provide safe ponds for translocated beaver or support riparian vegetation establishment. Like natural beaver dams, BDAs require maintenance (ideally by beaver) to persist, and they come and go, leaving a dynamic mosaic of habitat.