The City of Tigard Public Works Department is using beaver dam analogues (BDAs) in the urban environment to address stream degradation driven by intense hydromodification.
To improve the benefit and longevity of BDAs, W2r assisted the City of Tigard in developing guidance for BDA design and installation. The guidance included a classroom session, and a stepwise field assessment and design form. The form provides Tigard Public Works employees recommendations for BDA design dimensions such as height, orientation, and spacing distance according to site factors like channel slope, degree of channel incision, and proximity to infrastructure.
Implementing BDAs in the urban environment addresses degradation problems while they are tractable, mitigating major capital improvement project costs needed to address problems as they become severe and threaten critical infrastructure.
Client
City of Tigard
Keywords
Beaver dam analogue assessment, design, hydromodification
